Record Linux starter project validation

apps/editor_main.cpp

@@ -4,6 +4,7 @@
 #include <faset/editor/mcp.hpp>
 #include <faset/editor/session.hpp>
 #include <iostream>
+#include <memory>
 #include <thread>
 #ifdef FASET_HAS_EDITOR_UI
 #include <faset/editor/editor_ui.hpp>
@@ -40,7 +41,7 @@ void help() {
     std::cout
         << "Faset Editor\n"
            "  faset_editor                         Open the project launcher\n"
-           "  faset_editor --project PATH [--new NAME --dimension 2|3] [--scene RELATIVE_PATH]\n"
+           "  faset_editor --project PATH [--new NAME --dimension 2|3 [--language cpp|lua]] [--scene RELATIVE_PATH]\n"
            "  faset_editor --project PATH --mcp [--gui]\n"
            "  faset_editor --project PATH --command JSON [--wait]\n"
            "Options: --engine SDK_SOURCE, --headless, --frames N, --capture PATH.ppm\n"
@@ -52,9 +53,10 @@ int editor_main(int argc, char** argv) {
     using namespace faset::editor;
     try {
         std::filesystem::path project, engine = path_from_utf8(FASET_ENGINE_SOURCE), scene, capture;
-        std::string new_name, command;
+        std::string new_name, command, language = "cpp";
         int dimension = 3;
         bool mcp = false, gui = true, explicit_gui = false, wait = false;
+        bool explicit_language = false;
         std::uint64_t frames = 0;
         for (int i = 1; i < argc; ++i) {
             const std::string arg = argv[i];
@@ -74,6 +76,10 @@ int editor_main(int argc, char** argv) {
                 new_name = value();
             else if (arg == "--dimension")
                 dimension = std::stoi(value());
+            else if (arg == "--language") {
+                language = value();
+                explicit_language = true;
+            }
             else if (arg == "--scene")
                 scene = path_from_utf8(value());
             else if (arg == "--mcp")
@@ -100,30 +106,65 @@ int editor_main(int argc, char** argv) {
                 throw Error("cli.option", "Unknown option: " + arg);
         }
         require(!(mcp && !command.empty()), "cli.mode", "Choose MCP or a single command");
+        require(!explicit_language || !new_name.empty(), "cli.language",
+                "--language requires --new NAME");
+        require(language == "cpp" || language == "lua", "cli.language",
+                "Language must be cpp or lua");
         if (mcp && !explicit_gui)
             gui = false;
         require(!project.empty() || (gui && !mcp && new_name.empty()), "cli.project",
                 "Use --project PATH for command, MCP, or --new modes");
         auto previous_project = project;
+#ifdef FASET_HAS_EDITOR_UI
+        std::optional<ProjectSelection> retry_create;
+        std::string creation_error;
+#endif
         for (;;) {
             if (project.empty()) {
 #ifdef FASET_HAS_EDITOR_UI
                 const auto selection =
-                    run_project_launcher(engine, previous_project, frames, capture);
+                    run_project_launcher(engine, previous_project, frames, capture,
+                                         retry_create, creation_error);
+                retry_create.reset();
+                creation_error.clear();
                 if (!selection)
                     return 0;
                 project = selection->path;
                 new_name = selection->create ? selection->name : std::string();
                 dimension = selection->dimension;
+                language = selection->language;
+                explicit_language = selection->create;
 #else
                 throw Error("editor.gui_unavailable",
                             "This build has no graphical project launcher; use --project PATH");
 #endif
             }
-            Session session({std::filesystem::absolute(project), std::filesystem::absolute(engine),
-                             executable_directory(argv[0])});
-            if (!new_name.empty())
-                session.scaffold(new_name, dimension);
+            std::unique_ptr<Session> session_holder;
+            try {
+                session_holder = std::make_unique<Session>(SessionConfig{
+                    std::filesystem::absolute(project), std::filesystem::absolute(engine),
+                    executable_directory(argv[0])});
+                if (!new_name.empty()) {
+                    if (explicit_language)
+                        session_holder->scaffold(new_name, dimension, language);
+                    else
+                        session_holder->scaffold(new_name, dimension);
+                }
+            } catch (const std::exception& error) {
+#ifdef FASET_HAS_EDITOR_UI
+                if (gui && !new_name.empty()) {
+                    retry_create = ProjectSelection{std::filesystem::absolute(project),
+                                                    new_name, dimension, true, language};
+                    creation_error = error.what();
+                    project.clear();
+                    new_name.clear();
+                    scene.clear();
+                    continue;
+                }
+#endif
+                throw;
+            }
+            Session& session = *session_holder;
             const auto settings = session.project();
 #ifdef FASET_HAS_EDITOR_UI
             if (gui && std::filesystem::exists(project / "project.faset.json"))
@@ -167,6 +208,8 @@ int editor_main(int argc, char** argv) {
                 project.clear();
                 scene.clear();
                 new_name.clear();
+                explicit_language = false;
+                language = "cpp";
                 continue;
 #else
                 throw Error(

apps/project_launcher.cpp

@@ -75,6 +75,22 @@ ProjectSelection open_project(const fs::path& path) {
         throw std::runtime_error("Project name or scene type is invalid.");
     return {path, std::move(name), dimension, false};
 }
+bool fresh_destination(const fs::path& path) {
+    if (!fs::exists(path))
+        return true;
+    if (!fs::is_directory(path) || fs::is_symlink(path))
+        return false;
+    for (const auto& entry : fs::directory_iterator(path)) {
+        if (entry.path().filename() != ".faset" || !entry.is_directory() ||
+            entry.is_symlink())
+            return false;
+        for (const auto& internal : fs::directory_iterator(entry.path()))
+            if (internal.path().filename() != "cache" || !internal.is_directory() ||
+                internal.is_symlink() || !fs::is_empty(internal.path()))
+                return false;
+    }
+    return true;
+}
 Json recent_records(const fs::path& file) {
     try {
         auto j = read_json(file);
@@ -124,9 +140,11 @@ struct ProjectLauncher::Impl {
     std::optional<ProjectSelection> selected;
     bool create = false, cancelled = false, browsing = false, browser_valid = false;
     int dimension = 3;
+    std::string language = "cpp";
     std::string error;
     Impl(render::Renderer& r, const fs::path& engine, const fs::path& initial,
-         const fs::path& recents)
+         const fs::path& recents, const std::optional<ProjectSelection>& retry,
+         std::string creation_error)
         : renderer(r), ui(engine / "assets/fonts/NotoSans.ttf"),
           recents_file(recents.empty() ? recent_path() : recents) {
         auto theme = ui::Theme::load(engine / "assets/ui/dark.json");
@@ -147,13 +165,22 @@ struct ProjectLauncher::Impl {
         ui.set_ime(
             [this](bool enabled) { renderer.set_text_input(enabled); },
             [this](ui::Rect r) { renderer.set_text_input_area(r.x, r.y, r.width, r.height); });
-        const auto start = initial.empty() ? user_home() / "FasetProjects/MyGame" : initial;
+        const auto start = retry ? retry->path
+                                 : initial.empty() ? user_home() / "FasetProjects/MyGame" : initial;
         ui.update_text("launcher-path", path_to_utf8(start));
-        create = initial.empty();
+        create = retry ? retry->create : initial.empty();
+        if (retry) {
+            ui.update_text("launcher-name", retry->name);
+            dimension = retry->dimension;
+            language = retry->language;
+            error = std::move(creation_error);
+        }
         ui.find("launcher-open")->on_click = [this](Widget&) { set_mode(false); };
         ui.find("launcher-create")->on_click = [this](Widget&) { set_mode(true); };
         ui.find("launcher-2d")->on_click = [this](Widget&) { dimension = 2; };
         ui.find("launcher-3d")->on_click = [this](Widget&) { dimension = 3; };
+        ui.find("launcher-cpp")->on_click = [this](Widget&) { language = "cpp"; };
+        ui.find("launcher-lua")->on_click = [this](Widget&) { language = "lua"; };
         ui.find("launcher-submit")->on_click = [this](Widget&) { submit(); };
         ui.find("launcher-cancel")->on_click = [this](Widget&) { cancelled = true; };
         ui.find("launcher-name")->on_preview = [this](Widget&) { error.clear(); };
@@ -209,14 +236,14 @@ struct ProjectLauncher::Impl {
                     throw std::runtime_error("Enter a project name.");
                 if (name.size() > 256 || name.find_first_of("\r\n\t") != std::string::npos)
                     throw std::runtime_error("Use a short project name on one line.");
-                if (fs::exists(path) && (!fs::is_directory(path) || !fs::is_empty(path)))
+                if (!fresh_destination(path))
                     throw std::runtime_error("Create requires a new or empty directory.");
                 auto parent = path.parent_path();
                 while (!parent.empty() && !fs::exists(parent))
                     parent = parent.parent_path();
                 if (parent.empty() || !fs::is_directory(parent))
                     throw std::runtime_error("Project parent directory is unavailable.");
-                selected = ProjectSelection{path, name, dimension, true};
+                selected = ProjectSelection{path, name, dimension, true, language};
             } else
                 selected = open_project(path);
             error.clear();
@@ -351,14 +378,24 @@ struct ProjectLauncher::Impl {
         ui.find("launcher-create")->selected = create;
         ui.find("launcher-2d")->selected = dimension == 2;
         ui.find("launcher-3d")->selected = dimension == 3;
+        ui.find("launcher-cpp")->selected = language == "cpp";
+        ui.find("launcher-lua")->selected = language == "lua";
         ui.find("launcher-2d")->appearance =
             dimension == 2 ? Appearance::Quiet : Appearance::Default;
         ui.find("launcher-3d")->appearance =
             dimension == 3 ? Appearance::Quiet : Appearance::Default;
+        ui.find("launcher-cpp")->appearance =
+            language == "cpp" ? Appearance::Quiet : Appearance::Default;
+        ui.find("launcher-lua")->appearance =
+            language == "lua" ? Appearance::Quiet : Appearance::Default;
+        ui.find("launcher-language-hint")->text =
+            language == "cpp" ? "Compiled gameplay. Add Lua later if you need quick reloads."
+                              : "Lua gameplay reloads during development without a C++ rebuild.";
         for (const auto* id : {"launcher-name-label", "launcher-name", "launcher-dimension-label",
                                "launcher-dimensions", "launcher-name-group",
                                "launcher-name-space", "launcher-path-space",
-                               "launcher-dimension-group"})
+                               "launcher-dimension-group", "launcher-language-group",
+                               "launcher-language-space"})
             ui.find(id)->visible = create;
         ui.find("launcher-heading")->text = create ? "Create project" : "Open project";
         ui.find("launcher-submit")->text = create ? "Create project" : "Open project";
@@ -424,8 +461,11 @@ struct ProjectLauncher::Impl {
     }
 };
 ProjectLauncher::ProjectLauncher(render::Renderer& r, const fs::path& engine,
-                                 const fs::path& initial, const fs::path& recents)
-    : impl_(std::make_unique<Impl>(r, engine, initial, recents)) {}
+                                 const fs::path& initial, const fs::path& recents,
+                                 const std::optional<ProjectSelection>& retry,
+                                 std::string creation_error)
+    : impl_(std::make_unique<Impl>(r, engine, initial, recents, retry,
+                                   std::move(creation_error))) {}
 ProjectLauncher::~ProjectLauncher() = default;
 void ProjectLauncher::frame(const std::vector<render::Event>& events) {
     impl_->frame(events);
@@ -445,9 +485,11 @@ bool ProjectLauncher::cancelled() const {
 std::optional<ProjectSelection> run_project_launcher(const fs::path& engine,
                                                      const fs::path& initial,
                                                      std::uint64_t max_frames,
-                                                     const fs::path& capture) {
+                                                     const fs::path& capture,
+                                                     const std::optional<ProjectSelection>& retry,
+                                                     std::string creation_error) {
     render::Renderer renderer({1100, 720, "Faset Engine — Projects", false, true});
-    ProjectLauncher launcher(renderer, engine, initial);
+    ProjectLauncher launcher(renderer, engine, initial, {}, retry, std::move(creation_error));
     std::uint64_t frames = 0;
     while (!renderer.should_close() && !launcher.cancelled() && !launcher.selection() &&
            (max_frames == 0 || frames < max_frames)) {

assets/ui/project-launcher-layout.json

@@ -41,6 +41,15 @@
                 {"id": "launcher-3d", "kind": "button", "text": "3D", "layout": {"width": 116}}
               ]}
             ]},
+            {"id": "launcher-language-space", "kind": "row", "layout": {"height": 18}},
+            {"id": "launcher-language-group", "kind": "column", "layout": {"gap": 6}, "children": [
+              {"id": "launcher-language-label", "kind": "label", "text": "Gameplay language", "layout": {"height": 24}},
+              {"id": "launcher-languages", "kind": "row", "layout": {"height": 42, "gap": 4}, "children": [
+                {"id": "launcher-cpp", "kind": "button", "text": "C++", "layout": {"width": 116}},
+                {"id": "launcher-lua", "kind": "button", "text": "Lua", "layout": {"width": 116}}
+              ]},
+              {"id": "launcher-language-hint", "kind": "label", "text": "Compiled gameplay. Add Lua later if you need quick reloads.", "font_size": 12, "layout": {"height": 30}}
+            ]},
             {"id": "launcher-hint", "kind": "label", "text": "Open a directory containing project.faset.json.", "font_size": 13, "layout": {"height": 36}},
             {"id": "launcher-actions-space", "kind": "row", "layout": {"height": 22}},
             {"id": "launcher-actions-rule", "kind": "row", "layout": {"height": 1}},

cmake/BuildService.cmake

@@ -1,8 +1,18 @@
-add_library(faset_build_service STATIC ${PROJECT_SOURCE_DIR}/src/editor/build_service.cpp)
+add_library(faset_build_service STATIC
+  ${PROJECT_SOURCE_DIR}/src/editor/build_service.cpp
+  ${PROJECT_SOURCE_DIR}/src/editor/build_cache.cpp
+  ${PROJECT_SOURCE_DIR}/src/editor/build_diagnostics.cpp)
 target_include_directories(faset_build_service PUBLIC ${PROJECT_SOURCE_DIR}/include)
 target_compile_features(faset_build_service PUBLIC cxx_std_20)
 target_link_libraries(faset_build_service PUBLIC faset_core faset_scripting_project PRIVATE faset_assets faset_authoring Threads::Threads)
 if(BUILD_TESTING)
+  add_executable(faset_build_diagnostics_tests ${PROJECT_SOURCE_DIR}/tests/build_diagnostics_tests.cpp)
+  target_link_libraries(faset_build_diagnostics_tests PRIVATE faset_build_service)
+  add_test(NAME build_diagnostics COMMAND faset_build_diagnostics_tests)
+  add_executable(faset_build_cache_tests ${PROJECT_SOURCE_DIR}/tests/build_cache_tests.cpp)
+  target_link_libraries(faset_build_cache_tests PRIVATE faset_build_service)
+  target_compile_definitions(faset_build_cache_tests PRIVATE FASET_ENGINE_SOURCE="${PROJECT_SOURCE_DIR}")
+  add_test(NAME build_cache COMMAND faset_build_cache_tests)
   add_executable(faset_build_service_tests ${PROJECT_SOURCE_DIR}/tests/build_service_tests.cpp)
   target_link_libraries(faset_build_service_tests PRIVATE faset_build_service faset_assets)
   target_compile_definitions(faset_build_service_tests PRIVATE FASET_ENGINE_SOURCE="${PROJECT_SOURCE_DIR}")

cmake/Renderer.cmake

@@ -40,17 +40,13 @@ add_custom_command(OUTPUT "${FASET_SHADER_DIRECTORY}/compatibility.spv"
           -o "${FASET_SHADER_DIRECTORY}/compatibility.spv"
   DEPENDS "${PROJECT_SOURCE_DIR}/shaders/compatibility.hlsl" VERBATIM)
 add_custom_target(faset_shaders DEPENDS ${FASET_SHADER_OUTPUTS} "${FASET_SHADER_DIRECTORY}/compatibility.spv")
-add_library(faset_render "${PROJECT_SOURCE_DIR}/src/render/renderer.cpp" "${PROJECT_SOURCE_DIR}/src/render/math.cpp" "${PROJECT_SOURCE_DIR}/src/render/render_graph.cpp" "${PROJECT_SOURCE_DIR}/src/render/shader_contract.cpp" "${PROJECT_SOURCE_DIR}/src/render/lighting.cpp")
+add_library(faset_render "${PROJECT_SOURCE_DIR}/src/render/renderer.cpp" "${PROJECT_SOURCE_DIR}/src/render/math.cpp" "${PROJECT_SOURCE_DIR}/src/render/render_graph.cpp" "${PROJECT_SOURCE_DIR}/src/render/shader_contract.cpp")
 target_include_directories(faset_render PUBLIC "${PROJECT_SOURCE_DIR}/include")
 target_compile_features(faset_render PUBLIC cxx_std_20)
 target_link_libraries(faset_render PRIVATE Vulkan::Vulkan SDL3::SDL3 faset_core)
 target_compile_definitions(faset_render PRIVATE FASET_SHADER_DIRECTORY="${FASET_SHADER_DIRECTORY}")
 add_dependencies(faset_render faset_shaders)
 if(BUILD_TESTING)
-  add_executable(faset_render_lighting_policy_tests "${PROJECT_SOURCE_DIR}/tests/render_lighting_policy_tests.cpp")
-  target_link_libraries(faset_render_lighting_policy_tests PRIVATE faset_render)
-  add_test(NAME render_lighting_policy COMMAND faset_render_lighting_policy_tests)
-  set_tests_properties(render_lighting_policy PROPERTIES LABELS "p3")
   add_executable(faset_render_tests "${PROJECT_SOURCE_DIR}/tests/render_tests.cpp")
   target_link_libraries(faset_render_tests PRIVATE faset_render SDL3::SDL3)
   add_test(NAME render_graph COMMAND faset_render_tests --unit)
@@ -82,17 +78,5 @@ if(BUILD_TESTING)
   target_link_libraries(faset_render_window_tests PRIVATE faset_render SDL3::SDL3)
   add_test(NAME render_window_lifecycle COMMAND faset_render_window_tests "${CMAKE_BINARY_DIR}/window-test")
   set_tests_properties(render_window_lifecycle PROPERTIES LABELS "gpu;window" TIMEOUT 40 SKIP_RETURN_CODE 77)
-  add_executable(faset_p3_lighting_benchmark
-    "${PROJECT_SOURCE_DIR}/examples/renderer/p3_lighting_benchmark.cpp")
-  target_link_libraries(faset_p3_lighting_benchmark PRIVATE faset_render faset_core)
-  target_compile_definitions(faset_p3_lighting_benchmark PRIVATE
-    FASET_BENCHMARK_CONFIGURATION="$<CONFIG>")
-  add_test(NAME render_lighting_benchmark_schema COMMAND
-    "${Python3_EXECUTABLE}" "${PROJECT_SOURCE_DIR}/tests/test_p3_lighting_benchmark.py")
-  set_tests_properties(render_lighting_benchmark_schema PROPERTIES LABELS "p3" TIMEOUT 90)
-  add_test(NAME render_lighting_benchmark_smoke COMMAND
-    "${Python3_EXECUTABLE}" "${PROJECT_SOURCE_DIR}/tests/test_p3_lighting_benchmark.py"
-    --real-executable "$<TARGET_FILE:faset_p3_lighting_benchmark>")
-  set_tests_properties(render_lighting_benchmark_smoke PROPERTIES LABELS "gpu;p3" TIMEOUT 90)
 endif()
 install(FILES ${FASET_SHADER_OUTPUTS} DESTINATION shaders)

docs/manual/editor/lighting.md

@@ -1,92 +0,0 @@
-# Add lights to a 3D scene
-
-Add a **Light** component to a scene entity. The entity's transform places a point
-or spot light; its rotation aims a spot light along local negative Z. A directional
-light uses the entity's orientation. Light colors and intensity contribute to the
-mesh's linear PBR illumination before tone mapping. Sprites and UI retain their
-unlit tint.
-
-The version-1 `faset.light` component has three `kind` values:
-
-| Kind | Position and direction | Useful fields |
-| --- | --- | --- |
-| `directional` | Direction from the entity transform | `color`, `intensity`, `casts_shadow` |
-| `point` | Position from the entity transform; illuminates every direction | `color`, `intensity`, `range` |
-| `spot` | Position and local negative-Z direction | `color`, `intensity`, `range`, `inner_angle`, `outer_angle` |
-
-Angles are radians. A spot's inner angle must not exceed its outer angle. Intensity
-must be nonnegative and range positive. `enabled: false` keeps the component in the
-scene without contributing light. The `shadow_priority` integer is reserved for the
-bounded local-shadow scheduler; it does not change brightness.
-
-In the current rendering checkpoint, one enabled directional light can cast the
-existing single-map shadow. Point and spot lights illuminate meshes but do not yet
-cast shadows. The [P3 lighting plan](https://github.com/emil28092005/Faset_Engine/blob/main/docs/superpowers/plans/2026-09-24-p3-lighting.md)
-tracks cascades and the bounded local-shadow atlas. A scene with no Light component
-keeps the legacy white sun so older projects retain their appearance. Adding any
-Light component, even a disabled one, turns off that compatibility fallback. If
-several directionals are enabled, Faset chooses the one with the smallest stable
-entity ID and reports a diagnostic for the others.
-
-## Author a point light through MCP
-
-Use `faset_schema` to inspect the current field IDs, then send a `faset_scene_edit`
-batch with the document ID, current revision, and target entity ID. For example:
-
-```json
-{
-  "document": "REPLACE_WITH_DOCUMENT_ID",
-  "revision": 4,
-  "idempotency_key": "add-red-point-light",
-  "operations": [{
-    "op": "component.add",
-    "entity": "REPLACE_WITH_ENTITY_ID",
-    "type": "faset.light",
-    "fields": {
-      "kind": "point",
-      "color": [1, 0.15, 0.1, 1],
-      "intensity": 8,
-      "range": 6
-    }
-  }]
-}
-```
-
-Move the entity with its Transform component. `component.add` fills any omitted
-light fields from the version-1 schema; use `component.set` for later edits. See
-[MCP and command line](mcp.md) for revision and retry handling.
-
-## Supply lights directly from C++
-
-When building a `faset::render::Snapshot` yourself, set
-`authored_lights_present` to suppress the compatibility sun in a local-only scene.
-Provide a stable ID for each light so future shadow scheduling remains independent
-of submission order.
-
-```cpp
-faset::render::Snapshot snapshot;
-snapshot.authored_lights_present = true;
-
-faset::render::LocalLight point;
-point.kind = faset::render::LocalLight::Kind::Point;
-point.stable_id = "level/torch";
-point.position = {-2, 1.5f, 0};
-point.color = {1, 0.3f, 0.1f, 1};
-point.intensity = 8;
-point.range = 6;
-snapshot.local_lights.push_back(point);
-
-faset::render::LocalLight spot;
-spot.kind = faset::render::LocalLight::Kind::Spot;
-spot.stable_id = "level/lamp";
-spot.position = {2, 3, 0};
-spot.direction = {0, -1, 0};
-spot.inner_angle = 0.25f;
-spot.outer_angle = 0.55f;
-spot.intensity = 5;
-spot.range = 9;
-snapshot.local_lights.push_back(spot);
-```
-
-The renderer submits at most 128 local lights per frame in stable-ID order. Later
-P3 work adds explicit overflow diagnostics and measured light-list optimization.

docs/manual/getting-started/build.md

@@ -31,17 +31,27 @@ cmake --build --preset linux-debug --parallel
 ctest --preset linux-debug
 ```
 
-Create a project and open the native Editor:
+Create a runnable C++ or Lua starter and open the native Editor:
 
 ```sh
-build/linux-debug/faset_editor --project "$PWD/MyGame" --new MyGame --dimension 3
+build/linux-debug/faset_editor --project "$PWD/MyGame" --new MyGame --dimension 3 --language cpp
+build/linux-debug/faset_editor --project "$PWD/LuaGame" --new LuaGame --dimension 2 --language lua
 ```
 
 You can also run `build/linux-debug/faset_editor` without arguments to open the
-project launcher and create or select a project using the native interface.
+project launcher. Its Create view offers C++ 2D, C++ 3D, Lua 2D, and Lua 3D.
+Each explicit starter includes `Scenes/main.scene.json` with a player, ground,
+and a behavior bound to `Scripts/Gameplay.cpp` or `Scripts/main.lua`. 3D starters
+also include a camera and light. Existing files in a destination directory are
+never replaced by starter creation. The older `--new NAME --dimension 2|3`
+command without `--language` retains its original scene-free C++ scaffold.
 
 Use **Build** after changing `MyGame/Scripts/Gameplay.cpp`, then **Play**.
 The Player runs separately. Stop it before changing and rebuilding C++ gameplay.
+Lua starters declare their entry script in `project.faset.json`, install LuaLS
+annotations/configuration, and need no `Gameplay.cpp`. Use **Refresh Lua** after
+editing a Lua behavior declaration; development **Reload Lua** can apply a valid
+script edit to a running Player without recompiling C++.
 See [MCP and CLI](../editor/mcp.md) for headless authoring and automation.
 
 For an optimized build use `linux-release`. The `linux-sanitize` preset enables

docs/manual/scripting/lua.md

@@ -5,6 +5,23 @@ behaviors share the same runtime lifecycle, typed entity operations, scene compo
 and Inspector metadata. The Editor does not run gameplay code in its own process.
 There is no built-in script editor: edit `.lua` files in Zed or another external editor.
 
+## Start with a runnable Lua project
+
+Choose **Create project → Lua → 2D or 3D** in the native launcher, or run:
+
+```sh
+build/linux-debug/faset_editor --project "$PWD/LuaGame" --new LuaGame --dimension 2 --language lua
+```
+
+The starter creates `Scripts/main.lua`, a scene with a player and ground, and a
+manifest entry for that script. The player moves horizontally and jumps with the
+default input actions. The 3D choice also provides a camera and directional light.
+Open `Scripts/main.lua` in your external editor and change `speed` or
+`fixed_update`. **Refresh Lua** updates declared Inspector fields; **Reload Lua**
+updates a development Player after a valid edit without rebuilding native gameplay.
+The starter installs LuaLS declarations and `.luarc.json`; reopening it in Zed or
+another LuaLS-enabled editor provides completions for the Faset API.
+
 ## Enable Lua in a project
 
 Add explicit entry scripts to `project.faset.json`:

docs/superpowers/plans/2026-09-24-p3-lighting.md

@@ -42,9 +42,9 @@ Tasks 1–3 define the shared interfaces. Integrate Task 2's descriptor ABI befo
 
 **Files:** Modify `include/faset/render/renderer.hpp`, `src/authoring/schema.cpp`, `src/player/SceneView.cpp`, `tests/authoring_tests.cpp`, `tests/runtime_player_tests.cpp`, and relevant Manual authoring examples.
 
-**Interfaces:** Introduce `SunLight { stable_id, direction, color, intensity, casts_shadow }`, `LocalLight { Kind::Point|Spot, stable_id, position, direction, color, intensity, range, inner_angle, outer_angle, casts_shadow, shadow_priority }`, and `CameraFrustum { view, projection, near_plane, far_plane, perspective }`. Add `std::optional<SunLight> Snapshot::sun`, `std::vector<LocalLight> Snapshot::local_lights`, `bool Snapshot::authored_lights_present` (default false), and `std::optional<CameraFrustum> Snapshot::camera_frustum` after existing aggregate fields; retain `Snapshot::light_direction`. `SceneView::build` fills camera data for 3D scenes, sets authored-light presence even for disabled/future-version light components, and picks the first enabled directional by stable ID. A legacy sun is synthesized only when both sun and authored-light presence are absent.
+**Interfaces:** Introduce `SunLight { stable_id, direction, color, intensity, casts_shadow }`, `LocalLight { Kind::Point|Spot, stable_id, position, direction, color, intensity, range, inner_angle, outer_angle, casts_shadow, shadow_priority }`, and `CameraFrustum { view, projection, near_plane, far_plane, perspective }`. Add `std::optional<SunLight> Snapshot::sun`, `std::vector<LocalLight> Snapshot::local_lights`, and `std::optional<CameraFrustum> Snapshot::camera_frustum` after existing aggregate fields; retain `Snapshot::light_direction`. `SceneView::build` fills camera data for 3D scenes and picks the first enabled directional by stable ID.
 
-- [ ] **Step 1: Write failing schema/extraction tests.** Construct a version-1 scene with directional, point, and spot entities in one order and reversed order. Assert all local IDs/properties agree; authored sun color/intensity are preserved; a no-light scene has `authored_lights_present == false` and retains the default legacy sun, while a local-only or explicitly disabled-sun scene has the flag true and no sun. Extra directionals emit a diagnostic; invalid `range <= 0`, `inner_angle > outer_angle`, nonfinite color/transform, and unknown kind identify the entity/field. An essential assertion is:
+- [ ] **Step 1: Write failing schema/extraction tests.** Construct a version-1 scene with directional, point, and spot entities in one order and reversed order. Assert all local IDs/properties agree; authored sun color/intensity are preserved; no-light scene retains the default legacy sun; extra directionals emit a diagnostic; invalid `range <= 0`, `inner_angle > outer_angle`, nonfinite color/transform, and unknown kind identify the entity/field. An essential assertion is:
   ```cpp
   auto a = view.build(scene_with_three_lights(), 16.f / 9.f);
   auto b = view.build(reordered_scene_with_three_lights(), 16.f / 9.f);
@@ -54,14 +54,14 @@ Tasks 1–3 define the shared interfaces. Integrate Task 2's descriptor ABI befo
         "Light ordering follows stable IDs, not entity array order");
   ```
 - [ ] **Step 2: Run the focused tests red.** Run `cmake --preset linux-debug` and `cmake --build --preset linux-debug --target faset_authoring_tests faset_player_tests --parallel 4`; missing typed fields should fail compilation. If compilation succeeds, `ctest --test-dir build/linux-debug --output-on-failure --no-tests=error -R '^(authoring|player_scene_contracts)$'` must fail on a new behavioral assertion. Record the expected failure rather than assuming the build itself must be red.
-- [ ] **Step 3: Add schema defaults and extraction.** Keep builtin version 1; use `fields.value` for additive fields, normalize directions after the world transform, validate finite/color/range/cone values, sort by stable ID, and preserve the legacy fallback only when no authored light component exists. Set `camera_frustum` from the same unjittered view/projection used to form `view_projection`. Update direct C++ API examples to construct one point and one spot light.
+- [ ] **Step 3: Add schema defaults and extraction.** Keep builtin version 1; use `fields.value` for additive fields, normalize directions after the world transform, validate finite/color/range/cone values, sort by stable ID, and preserve the legacy fallback. Set `camera_frustum` from the same unjittered view/projection used to form `view_projection`. Update direct C++ API examples to construct one point and one spot light.
   ```cpp
   struct CameraFrustum {
       Mat4 view{identity}, projection{identity};
       float near_plane{0.1f}, far_plane{1000.f};
       bool perspective{true};
   };
-  // Snapshot::light_direction remains a fallback only if authored_lights_present is false.
+  // Snapshot::light_direction remains available to callers without Snapshot::sun.
   ```
 - [ ] **Step 4: Run focused tests green.** `ctest --test-dir build/linux-debug --output-on-failure -R '^(authoring|player_scene_contracts)$'` passes, including old version-1 scenes and exported-scene decoding.
 - [ ] **Step 5: Commit** `Expose authored sun, point, and spot lights in render snapshots`.

docs/superpowers/specs/2026-09-24-p3-lighting-design.md

@@ -12,7 +12,7 @@ P3 supplies one sun plus point and spot lights, camera-fitted cascaded sun shado
 
 Keep `faset.light` at builtin schema version 1 and add optional fields with defaults: `kind` (`directional`, `point`, `spot`, default `directional`), `enabled` (true), `color` (white), `intensity` (1, nonnegative), `range` (10, positive, for local lights), `inner_angle` (0.35 radians), `outer_angle` (0.70 radians, strictly below π/2), `casts_shadow` (true), and `shadow_priority` (integer 0). Existing fields and component IDs remain valid. Cross-field validation requires `0 <= inner_angle <= outer_angle`; local range, color channels, intensity, transforms, and cone directions must be finite. Invalid authored values return a diagnostic with entity and field rather than nonfinite GPU data. Missing new fields use the schema defaults.
 
-`Snapshot` retains `light_direction` for existing direct-render clients. Add an optional `SunLight`, a vector of `LocalLight`, an `authored_lights_present` flag (default false), and an optional explicit `CameraFrustum` containing unjittered view/projection matrices, near/far distances, and projection kind. `SceneView` populates these from the authoring scene and sets the flag if any authored light component exists, including a disabled or future-version component. Each light carries the stable entity/component identity, transformed position or normalized direction, color, intensity, range, cone angles, and shadow options. The first enabled directional light by stable ID is the sun; extra directionals produce a visible diagnostic until a later multi-sun design exists. The renderer synthesizes the legacy sun from `Snapshot::light_direction` only when `sun` is absent **and** `authored_lights_present` is false. Thus an old scene without light components keeps its previous appearance, while a local-only scene or explicitly disabled sun does not receive an unintended directional light. Low-level callers may set the flag to request a dark scene without authoring metadata. Local lights are ordered by stable ID to prevent reordering from changing atlas allocation or results. Point attenuation tends smoothly to zero at `range`; a spot multiplies it by a smooth inner-to-outer cone factor. The shader handles zero distance and invalid normals without NaN output.
+`Snapshot` retains `light_direction` for existing direct-render clients. Add an optional `SunLight`, a vector of `LocalLight`, and an optional explicit `CameraFrustum` containing unjittered view/projection matrices, near/far distances, and projection kind. `SceneView` populates these from the authoring scene. Each light carries the stable entity/component identity, transformed position or normalized direction, color, intensity, range, cone angles, and shadow options. The first enabled directional light by stable ID is the sun; extra directionals produce a visible diagnostic until a later multi-sun design exists. If there is no authored directional light, the renderer synthesizes the legacy sun from `Snapshot::light_direction`. Local lights are ordered by stable ID to prevent reordering from changing atlas allocation or results. Point attenuation tends smoothly to zero at `range`; a spot multiplies it by a smooth inner-to-outer cone factor. The shader handles zero distance and invalid normals without NaN output.
 
 Explicit camera frustum data is required for four cascades. If a low-level caller supplies only the legacy `view_projection`, the renderer uses one bounded legacy-compatible sun shadow view and reports `effective_sun_cascades = 1`; it never silently claims CSM. 2D sprite-only snapshots do not incur shadow work. The future temporal stage may jitter the main raster projection, but the shadow planner consumes the unjittered `CameraFrustum` exclusively.
 

docs/validation/p1-starters-linux-2026-09-24.md

@@ -0,0 +1,42 @@
+# P1 starter projects: Linux checkpoint (2026-09-24)
+
+This is a focused validation of the four explicit new-project choices in commit
+`cbb8b4508723e1a3a0bbd53c884e116a47b121dc`. It is not the final P1 acceptance
+record. The run used Linux 7.0.0-31-generic x86_64, Clang 21.1.8, CMake 4.2.3,
+and an NVIDIA GeForce RTX 2080 Ti with driver 595.84.
+
+The Editor CLI created C++ 2D, C++ 3D, Lua 2D, and Lua 3D projects in disposable
+directories with `--new`, `--dimension`, and `--language`. The test checked the
+project manifest, authored start scene, behavior binding, Lua script declaration,
+LuaLS files, and the absence of a C++ gameplay stub in Lua-only projects. A real
+Debug `faset_build` succeeded for C++ 2D and Lua 3D. Their built Players then
+validated and rendered **both** corresponding scene dimensions using the same
+language module, so all four templates exercised runtime schema and rendering.
+Each headless one-frame render reported `validation_errors: 0` on the physical GPU.
+
+| Project | Built Player used | `--validate` | One-frame headless render |
+| --- | --- | --- | --- |
+| C++ 2D | C++ 2D | passed | passed |
+| C++ 3D | C++ 2D | passed | passed |
+| Lua 2D | Lua 3D | passed | passed |
+| Lua 3D | Lua 3D | passed | passed |
+
+The C++ and Lua source files are identical within each language choice; the 2D/3D
+difference is the authored scene. Reusing one built Player per language therefore
+checks scene validity without repeating an identical native compile. The focused
+CTest cases `process_and_cook` and `editor_ui_launcher` passed 2/2. They include a
+two-service concurrent creation test: exactly one starter wins, and the other
+cannot overwrite it. A fresh Lua starter was initialized as a Git repository;
+`git check-ignore` confirmed `.faset/cache` is ignored while the LuaLS API
+declaration `.faset/lua/faset.lua` can be committed. A strict MkDocs build passed.
+
+These captures are representative output from the C++ 2D and 3D scenes. Lua
+scenes rendered the same layout with their own behavior module.
+
+![C++ 2D starter after one frame](p1-starters-linux-2026-09-24/cpp-2.png)
+
+![C++ 3D starter after one frame](p1-starters-linux-2026-09-24/cpp-3.png)
+
+The run did not test Windows, a relocated Release export, multi-frame gameplay
+input, or the final P1 build-cache integration. Those belong to the P1 acceptance
+matrix and must be recorded separately.

examples/renderer/p3_lighting_benchmark.cpp

@@ -1,233 +0,0 @@
-#include <faset/core/io.hpp>
-#include <faset/render/renderer.hpp>
-
-#include <algorithm>
-#include <array>
-#include <cstdint>
-#include <cstdlib>
-#include <filesystem>
-#include <fstream>
-#include <iomanip>
-#include <iostream>
-#include <stdexcept>
-#include <string>
-#include <string_view>
-
-using namespace faset::render;
-namespace fs = std::filesystem;
-
-namespace {
-struct Options {
-    unsigned lights{}, width{1920}, height{1080}, warmup{10}, frames{30}, run_index{};
-    bool shadows{}, validation{};
-    VisibilityMode visibility{VisibilityMode::Direct};
-    std::string commit{"unknown"}, driver{"unknown"};
-    fs::path csv, capture;
-};
-
-unsigned number(std::string_view text, std::string_view name) {
-    std::size_t end{};
-    const auto value = std::stoul(std::string(text), &end);
-    if (end != text.size() || value > 100000)
-        throw std::invalid_argument("Invalid value for " + std::string(name));
-    return static_cast<unsigned>(value);
-}
-
-Options parse(int argc, char** argv) {
-    Options options;
-    for (int i = 1; i < argc; ++i) {
-        const std::string name = argv[i];
-        if (name == "--list-runs") {
-            std::cout << "{\"lights\":[0,4,16,32,64,128],"
-                         "\"visibility\":[\"direct\",\"gpu-frustum\",\"gpu-occlusion\"],"
-                         "\"shadows\":[\"off\",\"on\"]}\n";
-            std::exit(0);
-        }
-        if (name == "--help") {
-            std::cout << "Usage: faset_p3_lighting_benchmark --lights 0|4|16|32|64|128 "
-                         "--shadows on|off --visibility direct|gpu-frustum|gpu-occlusion "
-                         "--csv PATH [--width N --height N --warmup N --frames N "
-                         "--run-index N --commit SHA --driver NAME --validation on|off "
-                         "--capture PATH]\n";
-            std::exit(0);
-        }
-        if (i + 1 >= argc)
-            throw std::invalid_argument("Missing value for " + name);
-        const std::string value = argv[++i];
-        if (name == "--lights") options.lights = number(value, name);
-        else if (name == "--width") options.width = number(value, name);
-        else if (name == "--height") options.height = number(value, name);
-        else if (name == "--warmup") options.warmup = number(value, name);
-        else if (name == "--frames") options.frames = number(value, name);
-        else if (name == "--run-index") options.run_index = number(value, name);
-        else if (name == "--commit") options.commit = value;
-        else if (name == "--driver") options.driver = value;
-        else if (name == "--csv") options.csv = faset::path_from_utf8(value);
-        else if (name == "--capture") options.capture = faset::path_from_utf8(value);
-        else if (name == "--shadows") {
-            if (value != "on" && value != "off")
-                throw std::invalid_argument("--shadows must be on or off");
-            options.shadows = value == "on";
-        } else if (name == "--validation") {
-            if (value != "on" && value != "off")
-                throw std::invalid_argument("--validation must be on or off");
-            options.validation = value == "on";
-        } else if (name == "--visibility") {
-            if (value == "direct") options.visibility = VisibilityMode::Direct;
-            else if (value == "gpu-frustum") options.visibility = VisibilityMode::GpuFrustum;
-            else if (value == "gpu-occlusion") options.visibility = VisibilityMode::GpuOcclusion;
-            else throw std::invalid_argument("Unknown visibility mode: " + value);
-        } else throw std::invalid_argument("Unknown option: " + name);
-    }
-    constexpr std::array allowed_lights{0u, 4u, 16u, 32u, 64u, 128u};
-    if (options.csv.empty() || options.width == 0 || options.height == 0 ||
-        options.frames == 0 || options.warmup > 1000 ||
-        std::find(allowed_lights.begin(), allowed_lights.end(), options.lights) ==
-            allowed_lights.end())
-        throw std::invalid_argument("Invalid benchmark configuration");
-    return options;
-}
-
-const char* mode_name(VisibilityMode mode) {
-    switch (mode) {
-    case VisibilityMode::Direct: return "direct";
-    case VisibilityMode::GpuFrustum: return "gpu-frustum";
-    case VisibilityMode::GpuOcclusion: return "gpu-occlusion";
-    }
-    return "unknown";
-}
-
-void csv_text(std::ostream& out, std::string_view value) {
-    out << '"';
-    for (const char c : value) {
-        if (c == '"') out << '"';
-        out << c;
-    }
-    out << '"';
-}
-
-Snapshot benchmark_scene(const Options& options) {
-    Snapshot scene;
-    scene.view_id = "p3-lighting-benchmark-fixed-scene";
-    scene.eye = {0, 0, 9};
-    scene.projection = perspective(.9f, float(options.width) / float(options.height), .1f, 100);
-    const auto view = look_at(scene.eye, {0, 0, 0});
-    scene.view_projection = multiply(scene.projection, view);
-    scene.camera_frustum = CameraFrustum{view, scene.projection, .1f, 100, true};
-    scene.authored_lights_present = true;
-    scene.clear_color = {.035f, .04f, .05f, 1};
-    DrawItem receiver;
-    receiver.mesh = cube_mesh();
-    receiver.model = transform({0, 0, -.15f}, {}, {10, 7.5f, .2f});
-    receiver.color = {.65f, .67f, .7f, 1};
-    receiver.roughness = .65f;
-    receiver.cast_shadow = options.shadows;
-    receiver.instance_key = "large-receiver";
-    scene.draws.push_back(receiver);
-    for (int i = 0; i < 9; ++i) {
-        DrawItem object;
-        object.mesh = cube_mesh();
-        object.model = transform({(float(i % 3) - 1.f) * 2.5f,
-                                  (float(i / 3) - 1.f) * 1.8f, .45f},
-                                 {}, {.42f, .42f, .6f});
-        object.color = {.6f + .1f * float(i % 3), .5f, .4f + .1f * float(i / 3), 1};
-        object.cast_shadow = options.shadows;
-        object.instance_key = "caster-" + std::to_string(i);
-        scene.draws.push_back(std::move(object));
-    }
-    for (unsigned i = 0; i < options.lights; ++i) {
-        LocalLight light;
-        light.kind = LocalLight::Kind::Point;
-        light.stable_id = "benchmark-light-" + std::to_string(i);
-        light.position = {(float(i % 8) - 3.5f) * 1.35f,
-                          (float((i / 8) % 8) - 3.5f) * .95f,
-                          2.f + .35f * float(i % 3)};
-        light.color = {.6f + .4f * float(i % 3 == 0),
-                       .6f + .4f * float(i % 3 == 1),
-                       .6f + .4f * float(i % 3 == 2), 1};
-        light.intensity = 5.f;
-        light.range = 8.f;
-        light.casts_shadow = options.shadows;
-        scene.local_lights.push_back(std::move(light));
-    }
-    return scene;
-}
-
-void benchmark(const Options& options) {
-    RendererConfig config;
-    config.width = options.width;
-    config.height = options.height;
-    config.headless = true;
-    config.validation = options.validation;
-    config.visibility_mode = options.visibility;
-    auto renderer = Renderer(config);
-    const auto scene = benchmark_scene(options);
-    for (unsigned i = 0; i < options.warmup; ++i)
-        renderer.render(scene);
-    if (!options.csv.parent_path().empty())
-        fs::create_directories(faset::native_io_path(options.csv.parent_path()));
-    std::ofstream csv(faset::native_io_path(options.csv));
-    if (!csv)
-        throw std::runtime_error("Cannot open benchmark CSV: " + faset::path_to_utf8(options.csv));
-    csv << "light_count,shadows,visibility,effective_visibility,lighting_path,"
-           "build_configuration,run_index,frame,"
-           "device,driver,commit,width,height,validation_enabled,validation_errors,"
-           "submitted_local_lights,omitted_local_lights,shadow_tiles,draw_calls,gpu_bytes,"
-           "gpu_main_raster_ms,gpu_post_raster_ms,gpu_post_visible,visibility_counters_valid,"
-           "gpu_shadow_ms,gpu_ms,cpu_ms,readback_cpu_ms\n";
-    csv << std::fixed << std::setprecision(6);
-    for (unsigned frame = 0; frame < options.frames; ++frame) {
-        renderer.render(scene);
-        const auto stats = renderer.stats();
-        if (stats.validation_errors != 0)
-            throw std::runtime_error("Vulkan validation error during benchmark");
-        if (stats.submitted_local_lights != options.lights || stats.omitted_local_lights != 0)
-            throw std::runtime_error("Renderer did not submit every requested local light");
-        if (stats.effective_visibility_mode != options.visibility)
-            throw std::runtime_error("Requested visibility path fell back during benchmark");
-        if (stats.gpu_main_raster_ms <= 0 || stats.gpu_ms <= 0)
-            throw std::runtime_error("GPU raster or frame timestamp was unavailable");
-        csv << options.lights << ',' << (options.shadows ? "on" : "off") << ','
-            << mode_name(options.visibility) << ',' << mode_name(stats.effective_visibility_mode)
-            << ",forward," << FASET_BENCHMARK_CONFIGURATION << ','
-            << options.run_index << ',' << frame << ',';
-        csv_text(csv, stats.device);
-        csv << ',';
-        csv_text(csv, options.driver);
-        csv << ',';
-        csv_text(csv, options.commit);
-        csv << ',' << options.width << ',' << options.height << ','
-            << (stats.validation_enabled ? 1 : 0) << ',' << stats.validation_errors << ','
-            << stats.submitted_local_lights << ',' << stats.omitted_local_lights
-            << ",0," << stats.draw_calls << ',' << stats.gpu_allocated_bytes << ','
-            << stats.gpu_main_raster_ms << ',' << stats.gpu_post_raster_ms << ','
-            << stats.gpu_post_visible << ',' << (stats.visibility_counters_valid ? 1 : 0)
-            << ",0," << stats.gpu_ms << ','
-            << stats.cpu_ms << ',' << stats.readback_cpu_ms << '\n';
-    }
-    if (!csv)
-        throw std::runtime_error("Cannot finish benchmark CSV: " + faset::path_to_utf8(options.csv));
-    if (!options.capture.empty())
-        renderer.capture(faset::native_io_path(options.capture));
-}
-} // namespace
-
-int benchmark_main(int argc, char** argv) {
-    try {
-        benchmark(parse(argc, argv));
-        return 0;
-    } catch (const std::exception& error) {
-        std::cerr << "P3 lighting benchmark: " << error.what() << '\n';
-        return 1;
-    }
-}
-
-#ifdef _WIN32
-int wmain(int argc, wchar_t** argv) {
-    return faset::run_utf8_main(argc, argv, benchmark_main);
-}
-#else
-int main(int argc, char** argv) {
-    return benchmark_main(argc, argv);
-}
-#endif

include/faset/editor/build_cache.hpp

@@ -0,0 +1,52 @@
+#pragma once
+
+#include <faset/editor/build_service.hpp>
+#include <faset/scripting/project.hpp>
+#include <filesystem>
+#include <optional>
+#include <string>
+
+namespace faset::editor {
+
+struct BuildInputs {
+    std::string source_hash;
+    std::string recipe_hash;
+    std::string toolchain_hash;
+    std::string fingerprint() const;
+};
+
+// Hash all files in Scripts and the active Lua declaration, not only the two
+// conventional gameplay files. Both Editor stale-state and builds use this key.
+std::string gameplay_source_hash(const std::filesystem::path& project_root,
+                                 const scripting::LuaProject& lua);
+BuildInputs capture_build_inputs(const BuildConfig& config, const scripting::LuaProject& lua);
+std::optional<std::string> configured_cmake_value(const BuildConfig& config,
+                                                   std::string_view key);
+
+// Copy a content-addressed, immutable Scripts tree for the native compiler.
+// Returning the same path for equal source bytes preserves Ninja incrementality.
+std::filesystem::path stage_gameplay_sources(const BuildConfig& config,
+                                              const BuildInputs& inputs,
+                                              const scripting::LuaProject& lua,
+                                              std::string_view job_id);
+
+// A compiler replaced at the same path may be invisible to Ninja. Invalidate
+// only this generated native tree; published build generations stay intact.
+void ensure_native_toolchain_stamp(const BuildConfig& config,
+                                   const std::filesystem::path& native_directory,
+                                   const BuildInputs& inputs);
+
+// Native build completes before package reuse is considered. Hash the actual
+// generated outputs, not their timestamps or just the gameplay sources.
+std::string build_package_key(const BuildInputs& inputs,
+                              const std::filesystem::path& native_directory,
+                              const std::string& configuration,
+                              const std::filesystem::path& player,
+                              const std::filesystem::path& exporter);
+
+// A hit is accepted only if the complete published file set and schema match
+// the manifest. Malformed or old manifests are safe cache misses.
+bool validate_build_generation(const std::filesystem::path& directory,
+                               const std::string& package_key);
+
+} // namespace faset::editor

include/faset/editor/build_diagnostics.hpp

@@ -0,0 +1,15 @@
+#pragma once
+
+#include <faset/core/json.hpp>
+#include <filesystem>
+#include <string_view>
+
+namespace faset::editor {
+
+// Parse compiler, MSVC/clang-cl and Lua output into bounded Editor-facing rows.
+// Only sources under the current project's Scripts directory receive a file
+// key, so clients cannot offer navigation to unrelated filesystem paths.
+Json parse_build_diagnostics(std::string_view raw_log, std::string_view phase,
+                             const std::filesystem::path& project_root);
+
+} // namespace faset::editor

include/faset/editor/build_service.hpp

@@ -3,6 +3,7 @@
 #include <filesystem>
 #include <memory>
 #include <string>
+#include <string_view>
 #include <vector>
 
 namespace faset::editor {
@@ -22,6 +23,7 @@ struct JobStatus {
     std::string id, kind, state{"queued"}, stage{"queued"};
     double progress{};
     std::string log, error;
+    Json diagnostics = Json::array();
     Json result = Json::object();
     bool finished() const {
         return state == "succeeded" || state == "failed" || state == "cancelled";
@@ -37,6 +39,9 @@ class BuildService {
     BuildService(const BuildService&) = delete;
     BuildService& operator=(const BuildService&) = delete;
     void scaffold(const std::string& name, int dimension);
+    // Explicit starter choice creates a runnable start scene. The legacy overload above
+    // remains intentionally scene-free for existing command-line and API callers.
+    void scaffold(const std::string& name, int dimension, std::string_view language);
     std::string start_build();
     std::string start_cook(Json resolved_scene);
     // Publishes output/generations/<id>; current.json changes only after all validation succeeds.

include/faset/editor/project_launcher.hpp

@@ -8,6 +8,7 @@ struct ProjectSelection {
     std::string name;
     int dimension = 3;
     bool create = false;
+    std::string language = "cpp";
 };
 // Records only existing, valid projects. Call after successful Session setup.
 void remember_project(const std::filesystem::path& project);
@@ -15,7 +16,9 @@ class ProjectLauncher {
   public:
     ProjectLauncher(render::Renderer&, const std::filesystem::path& engine_root,
                     const std::filesystem::path& initial_project = {},
-                    const std::filesystem::path& recent_store = {});
+                    const std::filesystem::path& recent_store = {},
+                    const std::optional<ProjectSelection>& retry = {},
+                    std::string creation_error = {});
     ~ProjectLauncher();
     void frame(const std::vector<render::Event>&);
     const render::Snapshot& snapshot() const;
@@ -30,5 +33,7 @@ class ProjectLauncher {
 std::optional<ProjectSelection>
 run_project_launcher(const std::filesystem::path& engine_root,
                      const std::filesystem::path& initial_project = {},
-                     std::uint64_t max_frames = 0, const std::filesystem::path& capture = {});
+                     std::uint64_t max_frames = 0, const std::filesystem::path& capture = {},
+                     const std::optional<ProjectSelection>& retry = {},
+                     std::string creation_error = {});
 } // namespace faset::editor

include/faset/editor/session.hpp

@@ -6,6 +6,7 @@
 #include <faset/editor/plugins.hpp>
 #include <memory>
 #include <mutex>
+#include <string_view>
 #include <thread>
 
 namespace faset::editor {
@@ -33,6 +34,7 @@ class Session {
         return plugins_ ? plugins_->panels() : Json::array();
     }
     void scaffold(const std::string& name, int dimension);
+    void scaffold(const std::string& name, int dimension, std::string_view language);
     const SessionConfig& config() const {
         return config_;
     }

include/faset/render/lighting.hpp

@@ -1,76 +0,0 @@
-#pragma once
-#include <faset/render/visibility.hpp>
-#include <cstddef>
-#include <cstdint>
-#include <span>
-#include <string>
-#include <vector>
-
-namespace faset::render {
-
-enum class ShadowDropReason { None, Unavailable, TileBudget, CasterBudget };
-enum class ShadowRedrawReason { EveryFrame };
-
-struct ShadowBudget {
-    std::uint32_t max_sun_views{4};
-    std::uint32_t max_local_faces{16};
-    std::uint32_t max_caster_draws{4096};
-    std::uint32_t max_local_lights{128};
-    std::uint32_t sun_atlas_size{2048};
-    std::uint32_t local_atlas_size{2048};
-    float max_shadow_distance{80};
-    bool sun_atlas_available{true};
-    bool local_atlas_available{true};
-};
-
-struct ShadowCasterBounds {
-    Bounds world;
-    std::uint32_t draw_index{}; // Index of the original source LOD-0 DrawItem.
-};
-
-struct ShadowView {
-    enum class Kind { Sun, Spot, Point };
-    Kind kind{Kind::Sun};
-    std::string light_id;
-    std::uint32_t face_index{};
-    std::uint32_t tile_index{};
-    std::uint32_t tile_origin_x{}, tile_origin_y{}, tile_size{}, usable_size{};
-    Mat4 view_projection{identity};
-    std::array<float, 4> atlas_scale_offset{};
-    std::array<float, 4> guarded_clamp{};
-    float split_near{}, split_far{};
-    float snapped_center_x{}, snapped_center_y{};
-    std::vector<std::uint32_t> caster_indices;
-    bool valid{};
-    ShadowDropReason reason{ShadowDropReason::None};
-    ShadowRedrawReason redraw_reason{ShadowRedrawReason::EveryFrame};
-};
-
-struct LocalShadowAssignment {
-    std::size_t source_index{};
-    std::uint32_t first_view{};
-    std::uint32_t face_count{};
-    bool valid{};
-    ShadowDropReason reason{ShadowDropReason::None};
-};
-
-struct ShadowPlan {
-    std::vector<ShadowView> sun_views; // Requested slots, including explicitly invalid ones.
-    std::vector<ShadowView> local_views; // Only complete, valid spot/point allocations.
-    std::vector<std::size_t> submitted_local_indices; // Priority/influence/stable-ID order.
-    std::vector<LocalShadowAssignment> local_assignments;
-    std::uint32_t requested_sun_cascades{}, effective_sun_cascades{};
-    std::uint32_t local_faces_requested{}, local_faces_used{};
-    std::uint32_t dropped_sun_views{}, dropped_local_faces{}, dropped_point_faces{};
-    std::uint32_t omitted_local_lights{}, caster_draws{};
-    std::uint32_t sun_atlas_size{}, local_atlas_size{};
-};
-
-// Stateless: every scheduled tile is cleared/redrawn; no prior-frame depth or
-// ownership is reused. Shadow casters are source LOD-0 world bounds, independent
-// of the camera/P2 visibility decision. This function performs no Vulkan work.
-ShadowPlan build_shadow_plan(const Snapshot& frame,
-                             std::span<const ShadowCasterBounds> casters,
-                             const ShadowBudget& budget = {});
-
-} // namespace faset::render

include/faset/render/renderer.hpp

@@ -80,34 +80,6 @@ struct Text {
     Color color{0.85f, 0.87f, 0.90f, 1};
     float size{14};
 };
-struct SunLight {
-    std::string stable_id;
-    Vec3 direction{-0.5f, -1, -0.3f};
-    Color color{1, 1, 1, 1};
-    float intensity{1};
-    bool casts_shadow{true};
-};
-struct LocalLight {
-    enum class Kind { Point, Spot };
-    Kind kind{Kind::Point};
-    std::string stable_id;
-    Vec3 position{};
-    Vec3 direction{0, 0, -1};
-    Color color{1, 1, 1, 1};
-    float intensity{1};
-    float range{10};
-    float inner_angle{0.35f};
-    float outer_angle{0.7f};
-    bool casts_shadow{true};
-    int shadow_priority{};
-};
-struct CameraFrustum {
-    Mat4 view{identity};
-    Mat4 projection{identity};
-    float near_plane{0.1f};
-    float far_plane{1000};
-    bool perspective{true};
-};
 struct Snapshot {
     // Optional scene viewport in drawable pixels (x, y, width, height); zero size uses the full
     // target.
@@ -128,12 +100,6 @@ struct Snapshot {
     // Distinguishes temporal histories when one Renderer displays different views.
     std::string view_id{};
     bool camera_cut{};
-    // Empty legacy scenes may use the renderer's compatibility sun. Any authored light
-    // component, including an explicitly disabled or opaque future one, suppresses it.
-    bool authored_lights_present{};
-    std::optional<SunLight> sun{};
-    std::vector<LocalLight> local_lights;
-    std::optional<CameraFrustum> camera_frustum{};
 };
 enum class VisibilityMode { Direct, GpuFrustum, GpuOcclusion };
 // CPU-only validation used before publishing a game or creating Vulkan pipelines.
@@ -183,7 +149,6 @@ struct FrameStats {
     std::uint64_t gpu_allocated_bytes{};
     std::uint32_t texture_count{};
     std::uint32_t vertices{}, draw_calls{}, culled_meshes{}, validation_errors{};
-    std::uint32_t submitted_local_lights{}, omitted_local_lights{};
     bool gpu_visibility_active{}, hzb_valid{};
     // Requested and actual paths for the last frame; actual may be less capable.
     VisibilityMode requested_visibility_mode{VisibilityMode::Direct};

mkdocs.yml

@@ -44,7 +44,6 @@ nav:
       - Editor workspace: editor/workspace.md
       - Scene templates: editor/templates.md
       - Assets and Blender: editor/assets.md
-      - Lighting: editor/lighting.md
       - GPU visibility and mesh LOD: editor/visibility-lod.md
       - Build, Play, and export: editor/export.md
       - Profiling and measurements: editor/profiling.md

shaders/baseline.slang

@@ -24,32 +24,6 @@ struct FrameParameters {
 [[vk::binding(1,0)]] SamplerState shadowSampler;
 [[vk::binding(2,0)]] Texture2D<float4> colorMap;
 [[vk::binding(3,0)]] SamplerState colorSampler;
-// Shared Direct/P2 graphics ABI. The legacy material set remains set 0;
-// GPU-only instance/visibility records occupy set 2.
-struct LightingHeader {
-    uint4 counts;                    // local count, sun enabled, sun shadow enabled, view count
-    float4 sunDirectionIntensity;    // xyz world-space ray direction, w intensity
-    float4 sunColor;
-    float4 cameraForwardShadowDistance;
-    float4 cascadeSplits;
-};
-struct LocalLightGpu {
-    float4 positionRange;
-    float4 directionCosOuter;
-    float4 colorIntensity;
-    float4 coneTypeShadowView;       // cos(inner), 0=point/1=spot, shadow view, flags
-    float4 reserved;
-};
-struct ShadowViewGpu {
-    column_major float4x4 viewProjection;
-    float4 tileScaleOffset;
-    float4 guardedClamp;
-    float4 biasFlags;
-};
-[[vk::binding(0,1)]] StructuredBuffer<LightingHeader> lightingFrame;
-[[vk::binding(1,1)]] StructuredBuffer<LocalLightGpu> localLights;
-[[vk::binding(2,1)]] StructuredBuffer<ShadowViewGpu> shadowViews;
-[[vk::binding(3,1)]] Texture2D<float> localShadowAtlas;
 [shader("vertex")]
 VertexOutput vertexMain(VertexInput v) {
     VertexOutput o;
@@ -58,22 +32,6 @@ VertexOutput vertexMain(VertexInput v) {
 }
 [shader("vertex")]
 float4 shadowMain(VertexInput v) : SV_Position { return mul(frame.lightViewProjection, float4(v.world,1)); }
-float3 directBRDF(float3 base, float rough, float metal, float3 n, float3 view, float3 l) {
-    const float pi = 3.14159265;
-    float nl = max(dot(n,l),0.0);
-    if (nl <= 0.0) return float3(0);
-    float3 halfVector = l + view;
-    float halfLengthSquared = dot(halfVector, halfVector);
-    float3 h = halfLengthSquared > 1e-8 ? halfVector * rsqrt(halfLengthSquared) : n;
-    float nv=max(dot(n,view),0.001), nh=max(dot(n,h),0.0), vh=max(dot(view,h),0.0);
-    float a=rough*rough, a2=a*a, denom=nh*nh*(a2-1.0)+1.0;
-    float d=a2/(pi*denom*denom+0.0001);
-    float k=(rough+1.0)*(rough+1.0)/8.0;
-    float g=(nl/(nl*(1.0-k)+k))*(nv/(nv*(1.0-k)+k));
-    float3 f0=lerp(float3(0.04),base,metal), fresnel=f0+(1.0-f0)*pow(1.0-vh,5.0);
-    float3 spec=d*g*fresnel/max(4.0*nv*nl,0.001);
-    return ((1.0-fresnel)*(1.0-metal)*base/pi+spec)*nl;
-}
 [shader("fragment")]
 float4 fragmentMain(VertexOutput v) : SV_Target {
     float4 sampled = colorMap.Sample(colorSampler, v.uv);
@@ -83,52 +41,28 @@ float4 fragmentMain(VertexOutput v) : SV_Target {
         return v.color * sampled;
     }
     float4 base = v.color * sampled;
-    LightingHeader lighting = lightingFrame[0];
-    float3 n=normalize(v.normal);
-    float3 viewDelta=frame.eye.xyz-v.world;
-    float viewLengthSquared=dot(viewDelta,viewDelta);
-    float3 view=viewLengthSquared > 1e-8 ? viewDelta*rsqrt(viewLengthSquared) : n;
+    const float pi = 3.14159265;
+    float3 n=normalize(v.normal), l=normalize(-frame.lightDirection.xyz), view=normalize(frame.eye.xyz-v.world), h=normalize(l+view);
+    float nl=max(dot(n,l),0.0), nv=max(dot(n,view),0.001), nh=max(dot(n,h),0.0), vh=max(dot(view,h),0.0);
     float rough=clamp(v.material.x,0.08,1.0), metal=saturate(v.material.y);
-    float3 linear=base.rgb*.12;
-    if (lighting.counts.y != 0 && lighting.sunDirectionIntensity.w > 0) {
-        float3 l=normalize(-lighting.sunDirectionIntensity.xyz);
-        float nl=max(dot(n,l),0.0);
-        float visibility=1.0;
-        if (lighting.counts.z != 0 && nl > 0) {
-            float4 lightClip=mul(frame.lightViewProjection,float4(v.world,1));
-            float3 projected=lightClip.xyz/lightClip.w;
-            float2 uv=projected.xy*.5+.5;
-            if(all(uv>=0.0)&&all(uv<=1.0)&&projected.z>=0.0&&projected.z<=1.0) {
-                visibility=0.0;
-                for(int y=-1;y<=1;++y) for(int x=-1;x<=1;++x) {
-                    float depth=shadowMap.SampleLevel(shadowSampler,uv+float2(x,y)/1024.0,0);
-                    visibility += projected.z-max(0.0008,0.003*(1.0-nl)) <= depth ? 1.0/9.0 : 0.0;
-                }
-            }
+    float a=rough*rough, a2=a*a, denom=nh*nh*(a2-1.0)+1.0;
+    float d=a2/(pi*denom*denom+0.0001);
+    float k=(rough+1.0)*(rough+1.0)/8.0;
+    float g=(nl/(nl*(1.0-k)+k))*(nv/(nv*(1.0-k)+k));
+    float3 f0=lerp(float3(0.04),base.rgb,metal), fresnel=f0+(1.0-f0)*pow(1.0-vh,5.0);
+    float3 spec=d*g*fresnel/max(4.0*nv*nl,0.001);
+    float4 lightClip=mul(frame.lightViewProjection,float4(v.world,1));
+    float3 projected=lightClip.xyz/lightClip.w;
+    float2 uv=projected.xy*.5+.5;
+    float visibility=1.0;
+    if(all(uv>=0.0)&&all(uv<=1.0)&&projected.z>=0.0&&projected.z<=1.0) {
+        visibility=0.0;
+        for(int y=-1;y<=1;++y) for(int x=-1;x<=1;++x) {
+            float depth=shadowMap.SampleLevel(shadowSampler,uv+float2(x,y)/1024.0,0);
+            visibility += projected.z-max(0.0008,0.003*(1.0-nl)) <= depth ? 1.0/9.0 : 0.0;
         }
-        linear += directBRDF(base.rgb, rough, metal, n, view, l) *
-                  lighting.sunColor.rgb * (lighting.sunDirectionIntensity.w * 3.0 * visibility);
-    }
-    for (uint i=0; i<lighting.counts.x; ++i) {
-        LocalLightGpu light=localLights[i];
-        float3 delta=light.positionRange.xyz-v.world;
-        float distanceSquared=max(dot(delta,delta),1e-6);
-        float distance=sqrt(distanceSquared);
-        float range=max(light.positionRange.w,1e-4);
-        if (distance >= range || light.colorIntensity.w <= 0) continue;
-        float3 l=delta/distance;
-        float relative=distance/range;
-        float cutoff=1.0-relative*relative*relative*relative;
-        float attenuation=cutoff*cutoff/(1.0+distanceSquared);
-        if (light.coneTypeShadowView.y > 0.5) {
-            float cosAngle=dot(-l,normalize(light.directionCosOuter.xyz));
-            float denominator=max(light.coneTypeShadowView.x-light.directionCosOuter.w,1e-4);
-            float cone=saturate((cosAngle-light.directionCosOuter.w)/denominator);
-            attenuation *= cone*cone*(3.0-2.0*cone);
-        }
-        linear += directBRDF(base.rgb, rough, metal, n, view, l) *
-                  light.colorIntensity.rgb * (light.colorIntensity.w * attenuation);
     }
+    float3 linear=base.rgb*.12 + ((1.0-fresnel)*(1.0-metal)*base.rgb/pi+spec)*nl*3.0*visibility;
     linear=linear/(1.0+linear);
     return float4(pow(max(linear,0),float3(1.0/2.2)),base.a);
 }

shaders/gpu_scene.slang

@@ -57,9 +57,9 @@ struct GpuFrameParameters {
     uint4 drawInfo; // x=visible ID range base; firstInstance is always zero
 };
 [[vk::push_constant]] ConstantBuffer<GpuFrameParameters> gpuFrame;
-[[vk::binding(0,2)]] StructuredBuffer<InstanceRecord> gfxInstances;
-[[vk::binding(1,2)]] StructuredBuffer<uint> gfxVisibleIds;
-[[vk::binding(2,2)]] StructuredBuffer<ViewRecord> gfxViews;
+[[vk::binding(0,1)]] StructuredBuffer<InstanceRecord> gfxInstances;
+[[vk::binding(1,1)]] StructuredBuffer<uint> gfxVisibleIds;
+[[vk::binding(2,1)]] StructuredBuffer<ViewRecord> gfxViews;
 
 // All indirect commands use firstInstance=0. The raw Vulkan index avoids the
 // BaseInstance read that Slang adds for SV_InstanceID (DrawParameters feature).

src/authoring/schema.cpp

@@ -156,15 +156,6 @@ void SchemaRegistry::validate_component(const Json& component) const {
     for (const auto& [id, value] : component["fields"].items())
         if (metadata["fields"].contains(id))
             validate_field(value, metadata["fields"][id]);
-    if (type == "faset.light") {
-        auto effective = default_fields(type);
-        effective.update(component.at("fields"));
-        if (effective.at("kind") == "spot")
-            require(effective.at("inner_angle").get<double>() <=
-                        effective.at("outer_angle").get<double>(),
-                    "validation.light_cone",
-                    "Spotlight inner_angle must not exceed outer_angle");
-    }
 }
 void SchemaRegistry::add_migration(const std::string& type, int from_version, Json rules) {
     require(contains(type) && from_version > 0 && from_version < schema(type).value("version", 1) &&
@@ -261,25 +252,9 @@ SchemaRegistry builtin_schemas() {
         {{"fov", Json{{"type", "number"}, {"default", 60.0}, {"min", 1.0}, {"max", 179.0}}},
          {"near", Json{{"type", "number"}, {"default", 0.1}, {"min", 0.001}}},
          {"far", Json{{"type", "number"}, {"default", 1000.0}, {"min", 0.01}}}});
-    add("faset.light", "Light",
-        {{"kind", Json{{"type", "string"},
-                        {"default", "directional"},
-                        {"enum", {"directional", "point", "spot"}}}},
-         {"enabled", field("boolean", true)},
-         {"color", field("color", {1, 1, 1, 1})},
-         {"intensity", Json{{"type", "number"}, {"default", 1.0}, {"min", 0.0}}},
-         {"range", Json{{"type", "number"}, {"default", 10.0}, {"min", 0.001}}},
-         {"inner_angle", Json{{"type", "number"},
-                              {"default", 0.35}, {"min", 0.0}, {"max", 1.55},
-                              {"unit", "radians"}}},
-         {"outer_angle", Json{{"type", "number"},
-                              {"default", 0.7}, {"min", 0.001}, {"max", 1.55},
-                              {"unit", "radians"}}},
-         {"casts_shadow", field("boolean", true)},
-         {"shadow_priority", Json{{"type", "integer"},
-                                   {"default", 0},
-                                   {"min", std::numeric_limits<int>::min()},
-                                   {"max", std::numeric_limits<int>::max()}}}});
+    add("faset.light", "Directional Light",
+        {{"color", field("color", {1, 1, 1, 1})},
+         {"intensity", Json{{"type", "number"}, {"default", 1.0}, {"min", 0.0}}}});
     for (int dimension : {2, 3}) {
         Json vector = dimension == 2 ? Json{0, 0} : Json{0, 0, 0};
         Json extents = dimension == 2 ? Json{0.5, 0.5} : Json{0.5, 0.5, 0.5};

src/editor/build_cache.cpp

@@ -0,0 +1,393 @@
+#include <faset/editor/build_cache.hpp>
+
+#include <faset/authoring/schema.hpp>
+#include <faset/core/hash.hpp>
+#include <faset/core/io.hpp>
+#include <faset/core/process.hpp>
+#include <cctype>
+#include <cstdlib>
+#include <set>
+#include <stdexcept>
+
+namespace faset::editor {
+namespace fs = std::filesystem;
+namespace {
+std::string normalized_hash(const Json& value) {
+    return sha256(value.dump());
+}
+std::pair<std::string, std::string> parse_define(const std::string& argument) {
+    if (!argument.starts_with("-D"))
+        throw std::invalid_argument("Gameplay configure arguments must be -DNAME=value options");
+    const auto equal = argument.find('=', 2);
+    if (equal == std::string::npos || equal == 2)
+        throw std::invalid_argument("Invalid gameplay configure definition");
+    const auto colon = argument.find(':', 2);
+    const auto key = argument.substr(2, colon < equal ? colon - 2 : equal - 2);
+    if (key.empty())
+        throw std::invalid_argument("Invalid gameplay configure definition");
+    return {key, argument.substr(equal + 1)};
+}
+void validate_configure_arguments(const BuildConfig& config) {
+    static const std::set<std::string> controlled = {
+        "FASET_GAMEPLAY_SOURCE_DIR", "FASET_ENABLE_LUA", "CMAKE_BUILD_TYPE", "BUILD_TESTING",
+        "FASET_BUILD_EDITOR", "FASET_BUILD_RENDERER", "FASET_BUILD_RUNTIME", "FASET_BUILD_ASSETS"};
+    for (const auto& argument : config.configure_arguments)
+        if (controlled.contains(parse_define(argument).first))
+            throw std::invalid_argument("Cannot override an engine-controlled CMake definition");
+}
+std::string configured_tool(const BuildConfig& config, std::string_view key,
+                            std::string fallback) {
+    if (auto value = configured_cmake_value(config, key))
+        return *value;
+    return fallback;
+}
+fs::path resolve_tool(const std::string& name, const fs::path& working_directory) {
+    const auto supplied = path_from_utf8(name);
+    if (supplied.has_parent_path())
+        return (supplied.is_absolute() ? supplied : working_directory / supplied).lexically_normal();
+    try {
+        return find_executable(name);
+    } catch (const std::exception&) {
+        // CMake reports a missing compiler. Keep the identity deterministic so
+        // fixture build tools can exercise publication without native compiling.
+        return supplied;
+    }
+}
+Json tool_identity(const std::string& name, const fs::path& working_directory) {
+    const auto resolved = resolve_tool(name, working_directory);
+    Json result = {{"path", path_to_utf8(resolved)}};
+    if (fs::is_regular_file(resolved))
+        result["sha256"] = sha256_file(resolved);
+    else
+        result["missing"] = true;
+    return result;
+}
+std::string slang_name(const BuildConfig& config) {
+    auto configured = configured_tool(config, "SLANGC_EXECUTABLE", "");
+    if (!configured.empty())
+        return configured;
+#ifdef _WIN32
+    const auto local = config.engine_root / ".cache/slang/bin/slangc.exe";
+#else
+    const auto local = config.engine_root / ".cache/slang/bin/slangc";
+#endif
+    if (fs::is_regular_file(local))
+        return path_to_utf8(local);
+    if (const char* sdk = std::getenv("VULKAN_SDK")) {
+#ifdef _WIN32
+        const auto sdk_tool = path_from_utf8(sdk) / "Bin/slangc.exe";
+#else
+        const auto sdk_tool = path_from_utf8(sdk) / "bin/slangc";
+#endif
+        if (fs::is_regular_file(sdk_tool))
+            return path_to_utf8(sdk_tool);
+    }
+    return "slangc";
+}
+Json recipe_files(const fs::path& engine_root) {
+    Json files = Json::object();
+    for (const auto& relative : {"CMakeLists.txt", "dependencies.lock.json",
+                                 "tools/compile_shader.py"}) {
+        const auto path = engine_root / relative;
+        files[relative] = fs::is_regular_file(path) ? Json(sha256_file(path)) : Json(nullptr);
+    }
+    const auto cmake = engine_root / "cmake";
+    if (fs::is_directory(cmake))
+        for (const auto& entry : fs::directory_iterator(cmake))
+            if (entry.is_regular_file() && entry.path().extension() == ".cmake")
+                files[generic_path_to_utf8(entry.path().lexically_relative(engine_root))] =
+                    sha256_file(entry.path());
+    return files;
+}
+bool within(const fs::path& path, const fs::path& directory) {
+    const auto relative = path.lexically_relative(directory);
+    if (relative.empty() || relative.is_absolute())
+        return false;
+    for (const auto& component : relative)
+        if (component == "..")
+            return false;
+    return true;
+}
+void refuse_symlink_ancestors(const fs::path& path) {
+    fs::path prefix;
+    for (const auto& component : path) {
+        prefix /= component;
+        std::error_code error;
+        if (fs::is_symlink(fs::symlink_status(prefix, error)))
+            throw std::runtime_error("Native build path contains a symlink: " +
+                                     path_to_utf8(prefix));
+    }
+}
+} // namespace
+
+std::optional<std::string> configured_cmake_value(const BuildConfig& config,
+                                                   std::string_view key) {
+    std::optional<std::string> result;
+    for (const auto& argument : config.configure_arguments) {
+        const auto [name, value] = parse_define(argument);
+        if (name == key)
+            result = value;
+    }
+    return result;
+}
+
+std::string BuildInputs::fingerprint() const {
+    return normalized_hash({{"format", "faset.build-inputs.v1"},
+                            {"source", source_hash},
+                            {"recipe", recipe_hash},
+                            {"toolchain", toolchain_hash}});
+}
+
+std::string gameplay_source_hash(const fs::path& project_root, const scripting::LuaProject& lua) {
+    Json files = Json::object();
+    const auto scripts = project_root / "Scripts";
+    if (fs::is_symlink(fs::symlink_status(scripts)))
+        throw std::runtime_error("Scripts directory must not be a symlink");
+    if (fs::is_directory(scripts))
+        for (const auto& entry : fs::recursive_directory_iterator(scripts)) {
+            if (entry.is_symlink())
+                throw std::runtime_error("Scripts source cannot be a symlink: " +
+                                         path_to_utf8(entry.path()));
+            if (entry.is_regular_file())
+                files[generic_path_to_utf8(entry.path().lexically_relative(project_root))] =
+                    sha256_file(entry.path());
+        }
+    return normalized_hash({{"format", "faset.gameplay-sources.v1"},
+                            {"files", files},
+                            {"lua", lua.fingerprint}});
+}
+
+BuildInputs capture_build_inputs(const BuildConfig& config, const scripting::LuaProject& lua) {
+    validate_configure_arguments(config);
+    BuildInputs result;
+    result.source_hash = gameplay_source_hash(config.project_root, lua);
+    result.recipe_hash = normalized_hash({{"format", "faset.build-recipe.v1"},
+                                          {"generator", config.generator},
+                                          {"configuration", config.configuration},
+                                          {"export_configuration", config.export_configuration},
+                                          {"configure_arguments", config.configure_arguments},
+                                          {"engine_files", recipe_files(config.engine_root)}});
+#ifdef _WIN32
+    constexpr auto default_c = "clang-cl", default_cxx = "clang-cl";
+#else
+    constexpr auto default_c = "clang", default_cxx = "clang++";
+#endif
+    result.toolchain_hash = normalized_hash(
+        {{"format", "faset.native-toolchain.v1"},
+         {"cmake", tool_identity(config.cmake, config.project_root)},
+         {"c", tool_identity(configured_tool(config, "CMAKE_C_COMPILER", default_c),
+                             config.project_root)},
+         {"cxx", tool_identity(configured_tool(config, "CMAKE_CXX_COMPILER", default_cxx),
+                               config.project_root)},
+         {"slang", tool_identity(slang_name(config), config.project_root)},
+         {"toolchain_file", tool_identity(configured_tool(config, "CMAKE_TOOLCHAIN_FILE", ""),
+                                          config.project_root)}});
+    return result;
+}
+
+fs::path stage_gameplay_sources(const BuildConfig& config, const BuildInputs& inputs,
+                                const scripting::LuaProject& lua, std::string_view job_id) {
+    const auto cache = config.cache_root.empty() ? config.project_root / ".faset" / "cache"
+                                                  : config.cache_root;
+    const auto snapshots = cache / "source-snapshots";
+    const auto destination = snapshots / inputs.source_hash;
+    const auto verified = [&](const fs::path& root) {
+        return fs::is_directory(root / "Scripts") && !fs::is_symlink(root) &&
+               gameplay_source_hash(root, lua) == inputs.source_hash;
+    };
+    if (fs::exists(destination)) {
+        if (!verified(destination))
+            throw std::runtime_error("Cached gameplay source snapshot is corrupt");
+        return destination / "Scripts";
+    }
+    const auto source = config.project_root / "Scripts";
+    if (!fs::is_directory(source) || fs::is_symlink(source))
+        throw std::runtime_error("Gameplay Scripts directory is missing or a symlink");
+    const auto staging = snapshots / (".staging-" + std::string(job_id));
+    if (fs::exists(staging))
+        throw std::runtime_error("Gameplay source staging directory already exists");
+    fs::create_directories(staging / "Scripts");
+    try {
+        for (const auto& entry : fs::recursive_directory_iterator(source)) {
+            if (entry.is_symlink())
+                throw std::runtime_error("Gameplay source snapshot contains a symlink");
+            const auto target = staging / "Scripts" / entry.path().lexically_relative(source);
+            if (entry.is_directory())
+                fs::create_directories(target);
+            else if (entry.is_regular_file()) {
+                fs::create_directories(target.parent_path());
+                fs::copy_file(entry.path(), target);
+            }
+        }
+        if (!verified(staging))
+            throw std::runtime_error("Gameplay sources changed while creating the build snapshot");
+        fs::rename(staging, destination);
+        return destination / "Scripts";
+    } catch (...) {
+        std::error_code ignored;
+        fs::remove_all(staging, ignored);
+        if (fs::exists(destination) && verified(destination))
+            return destination / "Scripts";
+        throw;
+    }
+}
+
+void ensure_native_toolchain_stamp(const BuildConfig& config, const fs::path& native_directory,
+                                   const BuildInputs& inputs) {
+    const auto project = fs::absolute(config.project_root).lexically_normal();
+    const auto base = fs::absolute(config.build_directory).lexically_normal();
+    const auto native = fs::absolute(native_directory).lexically_normal();
+    const auto cache = fs::absolute(config.cache_root.empty()
+                                        ? project / ".faset" / "cache"
+                                        : config.cache_root).lexically_normal();
+    const auto engine = fs::absolute(config.engine_root).lexically_normal();
+    if (native.parent_path() != base ||
+        (native.filename() != "Debug" && native.filename() != "Release" &&
+         native.filename() != "RelWithDebInfo"))
+        throw std::runtime_error("Native build path is outside its configured managed root");
+    const auto default_base = project / ".faset" / "build";
+    if ((within(base, project) && base != default_base) || within(project, base) ||
+        within(base, cache) || within(cache, base) || within(base, engine) ||
+        within(engine, base))
+        throw std::runtime_error("Native build root overlaps project, cache or engine files");
+    refuse_symlink_ancestors(native);
+    const auto stamp = native_directory / ".faset-toolchain.json";
+    bool matching = false, owned = false;
+    if (fs::is_regular_file(stamp) && !fs::is_symlink(stamp))
+        try {
+            const auto existing = read_json(stamp);
+            const auto format = existing.value("format", std::string()) ==
+                                "faset.toolchain-stamp";
+            const auto version = existing.value("version", 0);
+            owned = format &&
+                    ((version == 2 &&
+                      existing.value("project_root", std::string()) == path_to_utf8(project) &&
+                      existing.value("native_directory", std::string()) == path_to_utf8(native)) ||
+                     (version == 1 && base == default_base));
+            matching = owned &&
+                       existing.value("toolchain_hash", std::string()) == inputs.toolchain_hash;
+        } catch (const std::exception&) {
+            owned = false;
+        }
+    if (fs::exists(native_directory) && !owned)
+        throw std::runtime_error("Refusing to clear an unowned native build directory: " +
+                                 path_to_utf8(native));
+    if (!matching && fs::exists(native_directory))
+        fs::remove_all(native_directory);
+    fs::create_directories(native_directory);
+    atomic_write_json(stamp, {{"format", "faset.toolchain-stamp"},
+                              {"version", 2},
+                              {"project_root", path_to_utf8(project)},
+                              {"native_directory", path_to_utf8(native)},
+                              {"toolchain_hash", inputs.toolchain_hash}});
+}
+
+std::string build_package_key(const BuildInputs& inputs, const fs::path& native_directory,
+                              const std::string& configuration, const fs::path& player,
+                              const fs::path& exporter) {
+    Json files = Json::object();
+    for (const auto& [name, path] :
+         {std::pair{"player", player}, std::pair{"exporter", exporter},
+          std::pair{"cmake_cache", native_directory / "CMakeCache.txt"}}) {
+        if (!fs::is_regular_file(path) || fs::is_symlink(path))
+            throw std::runtime_error("Native build artifact is missing: " + path_to_utf8(path));
+        files[name] = sha256_file(path);
+    }
+    const auto shaders = native_directory / "shaders";
+    if (!fs::is_directory(shaders))
+        throw std::runtime_error("Native shader directory is missing");
+    for (const auto& entry : fs::recursive_directory_iterator(shaders)) {
+        if (entry.is_symlink())
+            throw std::runtime_error("Native shader is a symlink");
+        if (entry.is_regular_file())
+            files[generic_path_to_utf8(entry.path().lexically_relative(native_directory))] =
+                sha256_file(entry.path());
+    }
+    // On Windows, a changed runtime DLL must also invalidate a package hit.
+    for (const auto& root : {player.parent_path(), native_directory,
+                             native_directory / configuration}) {
+        if (!fs::is_directory(root))
+            continue;
+        for (const auto& entry : fs::directory_iterator(root)) {
+            auto extension = path_to_utf8(entry.path().extension());
+            for (auto& character : extension)
+                character = static_cast<char>(std::tolower(static_cast<unsigned char>(character)));
+            if (extension != ".dll")
+                continue;
+            if (!entry.is_regular_file() || entry.is_symlink())
+                throw std::runtime_error("Native runtime DLL is not a regular file");
+            files["dll:" + path_to_utf8(entry.path().filename())] = sha256_file(entry.path());
+        }
+    }
+    return normalized_hash({{"format", "faset.package-key.v1"},
+                            {"inputs", inputs.fingerprint()},
+                            {"configuration", configuration},
+                            {"files", files}});
+}
+
+bool validate_build_generation(const fs::path& directory, const std::string& package_key) {
+    try {
+        if (!fs::is_directory(directory) || fs::is_symlink(directory))
+            return false;
+        const auto manifest_file = directory / "manifest.json";
+        if (!fs::is_regular_file(manifest_file) || fs::is_symlink(manifest_file))
+            return false;
+        const auto manifest = read_json(manifest_file);
+        if (manifest.at("format") != "faset.build" || manifest.at("version") != 2 ||
+            manifest.at("package_key") != package_key || !manifest.at("files").is_array())
+            return false;
+        std::set<std::string> expected;
+        for (const auto& record : manifest.at("files")) {
+            const auto name = record.at("path").get<std::string>();
+            const auto relative = path_from_utf8(name);
+            if (relative.empty() || relative.is_absolute() || name == "manifest.json" ||
+                generic_path_to_utf8(relative) != name)
+                return false;
+            for (const auto& component : relative)
+                if (component == "." || component == "..")
+                    return false;
+            if (!expected.insert(name).second)
+                return false;
+            auto file = directory;
+            for (const auto& component : relative) {
+                file /= component;
+                if (fs::is_symlink(file))
+                    return false;
+            }
+            if (!fs::is_regular_file(file) || fs::is_symlink(file) ||
+                sha256_file(file) != record.at("sha256").get<std::string>() ||
+                fs::file_size(file) != record.at("size").get<std::uintmax_t>())
+                return false;
+        }
+        for (const auto& entry : fs::recursive_directory_iterator(directory)) {
+            if (entry.is_symlink())
+                return false;
+            if (entry.is_regular_file()) {
+                const auto name = generic_path_to_utf8(entry.path().lexically_relative(directory));
+                if (name != "manifest.json" && !expected.contains(name))
+                    return false;
+            }
+        }
+        const auto player_name = manifest.at("player").get<std::string>();
+        const auto schema_name = manifest.at("schema").get<std::string>();
+        if (!expected.contains(player_name) || !expected.contains(schema_name) ||
+            !expected.contains("faset_schema_exporter" + fs::path(player_name).extension().string()))
+            return false;
+        for (const auto* shader : {"vertexMain", "fragmentMain", "shadowMain",
+                                   "gpuVertexMain", "gpuShadowMain", "gpuCullMain",
+                                   "gpuHzbMain", "gpuPostCullMain"})
+            for (const auto* extension : {".spv", ".reflection.json"})
+                if (!expected.contains("shaders/" + std::string(shader) + extension))
+                    return false;
+        const auto schema = read_json(directory / schema_name);
+        if (schema.at("format") != "faset.schema" || schema.at("version") != 1 ||
+            schema.at("build_fingerprint") != manifest.at("fingerprint"))
+            return false;
+        (void)authoring::gameplay_schemas(schema);
+        return true;
+    } catch (const std::exception&) {
+        return false;
+    }
+}
+
+} // namespace faset::editor

src/editor/build_diagnostics.cpp

@@ -0,0 +1,147 @@
+#include <faset/editor/build_diagnostics.hpp>
+
+#include <faset/core/io.hpp>
+#include <algorithm>
+#include <cctype>
+#include <regex>
+#include <sstream>
+
+namespace faset::editor {
+namespace {
+constexpr std::size_t max_rows = 200;
+constexpr std::size_t max_line = 8192;
+constexpr std::size_t max_message = 2048;
+
+std::string strip_ansi(std::string_view text) {
+    std::string clean;
+    clean.reserve(text.size());
+    for (std::size_t index = 0; index < text.size(); ++index) {
+        if (text[index] == '\x1b' && index + 1 < text.size() && text[index + 1] == '[') {
+            index += 2;
+            while (index < text.size() && !(text[index] >= '@' && text[index] <= '~'))
+                ++index;
+            continue;
+        }
+        clean += text[index];
+    }
+    return clean;
+}
+std::string normalize_path(std::string path) {
+    std::replace(path.begin(), path.end(), '\\', '/');
+    path = std::filesystem::path(path).lexically_normal().generic_string();
+    while (path.size() > 1 && path.back() == '/')
+        path.pop_back();
+    return path;
+}
+bool has_windows_drive(std::string_view path) {
+    return path.size() >= 2 && std::isalpha(static_cast<unsigned char>(path[0])) &&
+           path[1] == ':';
+}
+std::string lower_ascii(std::string value) {
+    for (auto& character : value)
+        character = static_cast<char>(std::tolower(static_cast<unsigned char>(character)));
+    return value;
+}
+std::string project_source(std::string raw, const std::filesystem::path& project_root) {
+    if (raw.starts_with("lua: "))
+        raw.erase(0, 5);
+    std::replace(raw.begin(), raw.end(), '\\', '/');
+    for (const auto& component : std::filesystem::path(raw))
+        if (component == "..")
+            return {};
+    const auto path = normalize_path(std::move(raw));
+    const auto root = normalize_path(path_to_utf8(project_root));
+    std::string relative;
+    if (!path.empty() && path[0] != '/' && !has_windows_drive(path))
+        relative = path;
+    else {
+        const auto windows = has_windows_drive(path) && has_windows_drive(root);
+        const auto comparable_path = windows ? lower_ascii(path) : path;
+        const auto comparable_root = windows ? lower_ascii(root) : root;
+        if (comparable_path.size() <= comparable_root.size() ||
+            !comparable_path.starts_with(comparable_root) ||
+            comparable_path[comparable_root.size()] != '/')
+            return {};
+        relative = path.substr(root.size() + 1);
+    }
+    if (!relative.starts_with("Scripts/") || relative.size() <= 8)
+        return {};
+    if (relative.find("/../") != std::string::npos || relative.ends_with("/.."))
+        return {};
+    return relative;
+}
+int positive_number(const std::string& text) {
+    try {
+        const auto value = std::stoll(text);
+        return value > 0 && value <= 100000000 ? static_cast<int>(value) : 0;
+    } catch (const std::exception&) {
+        return 0;
+    }
+}
+} // namespace
+
+Json parse_build_diagnostics(std::string_view raw_log, std::string_view phase,
+                             const std::filesystem::path& project_root) {
+    static const std::regex msvc(
+        R"(^(.+)\(([0-9]+)(?:,([0-9]+))?\)\s*:\s*(fatal error|error|warning|note)\s*([A-Za-z]+[0-9]+)?\s*:\s*(.*)$)");
+    static const std::regex clang_column(
+        R"(^(.+):([0-9]+):([0-9]+):\s*(fatal error|error|warning|note)(?:\s+([A-Za-z]+[0-9]+))?\s*:\s*(.*)$)");
+    static const std::regex clang_line(
+        R"(^(.+):([0-9]+):\s*(fatal error|error|warning|note)(?:\s+([A-Za-z]+[0-9]+))?\s*:\s*(.*)$)");
+    static const std::regex lua(R"(^(.+\.lua):([0-9]+):\s*(.*)$)");
+    Json rows = Json::array();
+    std::istringstream stream{std::string(raw_log)};
+    std::string raw;
+    while (rows.size() < max_rows && std::getline(stream, raw)) {
+        if (raw.size() > max_line)
+            raw.resize(max_line);
+        auto line = strip_ansi(raw);
+        if (!line.empty() && line.back() == '\r')
+            line.pop_back();
+        std::smatch match;
+        std::string file, message, severity, code;
+        int row = 0, column = 0;
+        bool has_column = false;
+        if (std::regex_match(line, match, msvc) ||
+            std::regex_match(line, match, clang_column)) {
+            file = match[1].str();
+            row = positive_number(match[2].str());
+            has_column = !match[3].str().empty();
+            column = positive_number(match[3].str());
+            severity = match[4].str();
+            code = match[5].str();
+            message = match[6].str();
+        } else if (std::regex_match(line, match, clang_line)) {
+            file = match[1].str();
+            row = positive_number(match[2].str());
+            severity = match[3].str();
+            code = match[4].str();
+            message = match[5].str();
+        } else if (std::regex_match(line, match, lua)) {
+            file = match[1].str();
+            row = positive_number(match[2].str());
+            severity = "error";
+            message = match[3].str();
+        } else
+            continue;
+        if (row == 0 || (has_column && column == 0))
+            continue;
+        if (severity == "fatal error")
+            severity = "error";
+        if (message.size() > max_message)
+            message.resize(max_message);
+        Json diagnostic{{"severity", severity},
+                        {"phase", std::string(phase)},
+                        {"message", message},
+                        {"line", row}};
+        if (column > 0)
+            diagnostic["column"] = column;
+        if (!code.empty())
+            diagnostic["code"] = code;
+        if (auto relative = project_source(file, project_root); !relative.empty())
+            diagnostic["file"] = std::move(relative);
+        rows.push_back(std::move(diagnostic));
+    }
+    return rows;
+}
+} // namespace faset::editor

src/editor/build_service.cpp

@@ -1,3 +1,4 @@
+#include <algorithm>
 #include <atomic>
 #include <cctype>
 #include <chrono>
@@ -6,9 +7,12 @@
 #include <faset/assets/asset_data.hpp>
 #include <faset/assets/asset_pipeline.hpp>
 #include <faset/authoring/schema.hpp>
+#include <faset/authoring/service.hpp>
 #include <faset/core/hash.hpp>
 #include <faset/core/io.hpp>
 #include <faset/core/process.hpp>
+#include <faset/editor/build_cache.hpp>
+#include <faset/editor/build_diagnostics.hpp>
 #include <faset/editor/build_service.hpp>
 #include <faset/scripting/project.hpp>
 #include <fstream>
@@ -89,11 +93,107 @@ fs::path build_executable(const fs::path& build, const std::string& configuratio
     }
     throw std::runtime_error("Build did not produce " + target);
 }
+Json starter_scene(const std::string& name, int dimension, std::string_view language) {
+    const auto schemas = authoring::builtin_schemas();
+    auto scene = authoring::make_scene(name + " — Starter", dimension);
+    scene["simulation"] = authoring::default_simulation_settings();
+    auto add_component = [&](Json& entity, std::string type, Json fields) {
+        entity["components"].push_back({{"id", new_id()},
+                                        {"type", std::move(type)},
+                                        {"version", 1},
+                                        {"fields", std::move(fields)}});
+    };
+    auto ground = authoring::make_entity(schemas, "Ground");
+    auto& ground_pose = ground["components"][0]["fields"];
+    ground_pose["position"] = {0, -1, 0};
+    ground_pose["scale"] = dimension == 2 ? Json::array({12, 1, 1}) : Json::array({12, 1, 12});
+    if (dimension == 2) {
+        add_component(ground, "faset.sprite", {{"size", {1, 1}},
+                                                {"color", {0.20, 0.25, 0.31, 1}}});
+    } else {
+        add_component(ground, "faset.mesh", {{"asset", "builtin:cube"},
+                                              {"color", {0.20, 0.25, 0.31, 1}}});
+    }
+    auto ground_body = schemas.default_fields("faset.rigid_body_" + std::to_string(dimension) +
+                                              "d");
+    ground_body["body_type"] = "static";
+    add_component(ground, "faset.rigid_body_" + std::to_string(dimension) + "d",
+                  std::move(ground_body));
+    scene["entities"].push_back(std::move(ground));
+
+    auto actor = authoring::make_entity(schemas, "Player");
+    actor["components"][0]["fields"]["position"] = {0, 1, 0};
+    if (dimension == 2) {
+        add_component(actor, "faset.sprite", {{"size", {0.8, 0.8}},
+                                               {"color", {0.25, 0.72, 0.85, 1}}});
+    } else {
+        actor["components"][0]["fields"]["scale"] = {0.8, 0.8, 0.8};
+        add_component(actor, "faset.mesh", {{"asset", "builtin:cube"},
+                                             {"color", {0.25, 0.72, 0.85, 1}}});
+    }
+    add_component(actor, "faset.rigid_body_" + std::to_string(dimension) + "d",
+                  schemas.default_fields("faset.rigid_body_" + std::to_string(dimension) + "d"));
+    add_component(actor, language == "lua" ? "starter.player" : "gameplay.character",
+                  {{"speed", 4.0}, {"jump_speed", 5.0}});
+    scene["entities"].push_back(std::move(actor));
+    if (dimension == 3) {
+        auto camera = authoring::make_entity(schemas, "Camera");
+        camera["components"][0]["fields"]["position"] = {0, 2.5, 8};
+        camera["components"][0]["fields"]["rotation"] = {-0.18, 0, 0};
+        add_component(camera, "faset.camera", schemas.default_fields("faset.camera"));
+        scene["entities"].push_back(std::move(camera));
+        auto sun = authoring::make_entity(schemas, "Sun");
+        add_component(sun, "faset.light", schemas.default_fields("faset.light"));
+        scene["entities"].push_back(std::move(sun));
+    }
+    // Validate every built-in component now; the behavior component is validated by
+    // SchemaExporter from the selected C++/Lua module during the first build.
+    auto builtins = scene;
+    for (auto& entity : builtins["entities"]) {
+        auto& components = entity["components"].get_ref<Json::array_t&>();
+        std::erase_if(components, [](const Json& component) {
+            return !component.at("type").get<std::string>().starts_with("faset.");
+        });
+    }
+    authoring::validate_scene(builtins, schemas);
+    return scene;
+}
+struct StarterCreateLock {
+    fs::path path;
+    explicit StarterCreateLock(const fs::path& root) : path(root / ".faset/starter-create.lock") {
+        if (!fs::create_directory(path))
+            throw std::runtime_error("Another project creation is in progress; remove a stale " +
+                                     path_to_utf8(path) + " only after closing that Editor");
+    }
+    ~StarterCreateLock() {
+        std::error_code ignored;
+        fs::remove_all(path, ignored);
+    }
+    StarterCreateLock(const StarterCreateLock&) = delete;
+    StarterCreateLock& operator=(const StarterCreateLock&) = delete;
+};
+void require_new_starter_directory(const fs::path& root) {
+    // BuildService creates .faset/cache in its constructor. Any other content is
+    // user-owned, including a previous starter, and must be left intact.
+    for (const auto& entry : fs::directory_iterator(root)) {
+        if (entry.path().filename() != ".faset" || !entry.is_directory() ||
+            entry.is_symlink())
+            throw std::runtime_error("Create requires a new or empty project directory");
+        for (const auto& internal : fs::directory_iterator(entry.path())) {
+            if (internal.path().filename() == "starter-create.lock" &&
+                internal.is_directory() && !internal.is_symlink())
+                continue;
+            if (internal.path().filename() != "cache" || !internal.is_directory() ||
+                internal.is_symlink() || !fs::is_empty(internal.path()))
+                throw std::runtime_error("Create requires a new or empty project directory");
+        }
+    }
+}
 } // namespace
 Json JobStatus::json() const {
     return {{"id", id},       {"kind", kind},         {"state", state},
             {"stage", stage}, {"progress", progress}, {"log", log},
-            {"error", error}, {"result", result}};
+            {"error", error}, {"diagnostics", diagnostics}, {"result", result}};
 }
 void write_cooked_scene(const fs::path& path, const Json& scene) {
     validate_scene(scene);
@@ -198,6 +298,13 @@ struct BuildService::Impl {
     std::string run(Job& job, std::vector<std::string> arguments, const fs::path& cwd) {
         if (job.cancelled)
             throw Cancelled{};
+        std::string phase;
+        std::size_t diagnostics_before;
+        {
+            std::lock_guard lock(job.mutex);
+            phase = job.status.stage;
+            diagnostics_before = job.status.diagnostics.size();
+        }
         std::string description = "$";
         for (const auto& argument : arguments)
             description += " " + Json(argument).dump();
@@ -205,6 +312,35 @@ struct BuildService::Impl {
         log(job, description);
         Process process({std::move(arguments), cwd, {}});
         std::string output;
+        std::string pending;
+        const auto collect_diagnostics = [&](std::string_view chunk, bool final) {
+            pending.append(chunk);
+            std::size_t newline;
+            while ((newline = pending.find('\n')) != std::string::npos) {
+                const auto line = pending.substr(0, newline + 1);
+                pending.erase(0, newline + 1);
+                const auto found = parse_build_diagnostics(line, phase, config.project_root);
+                if (found.empty())
+                    continue;
+                std::lock_guard lock(job.mutex);
+                for (const auto& row : found) {
+                    if (job.status.diagnostics.size() >= 200)
+                        break;
+                    job.status.diagnostics.push_back(row);
+                }
+            }
+            if (final && !pending.empty()) {
+                const auto found = parse_build_diagnostics(pending, phase, config.project_root);
+                std::lock_guard lock(job.mutex);
+                for (const auto& row : found) {
+                    if (job.status.diagnostics.size() >= 200)
+                        break;
+                    job.status.diagnostics.push_back(row);
+                }
+                pending.clear();
+            } else if (pending.size() > 8192)
+                pending.erase(0, pending.size() - 8192);
+        };
         while (true) {
             if (job.cancelled) {
                 process.cancel();
@@ -214,14 +350,29 @@ struct BuildService::Impl {
             }
             auto poll = process.poll();
             log(job, poll.output);
+            collect_diagnostics(poll.output, !poll.running);
             output += poll.output;
             if (output.size() > max_log_bytes)
                 output.erase(0, output.size() - max_log_bytes);
             if (!poll.running) {
-                if (poll.exit_code.value_or(1) != 0)
+                if (poll.exit_code.value_or(1) != 0) {
+                    std::lock_guard lock(job.mutex);
+                    bool has_error = false;
+                    for (std::size_t index = diagnostics_before;
+                         index < job.status.diagnostics.size(); ++index)
+                        if (job.status.diagnostics[index].value("severity", "") == "error")
+                            has_error = true;
+                    if (!has_error && job.status.diagnostics.size() < 200)
+                        job.status.diagnostics.push_back(
+                            {{"severity", "error"},
+                             {"phase", phase},
+                             {"message", "Process exited with code " +
+                                             std::to_string(poll.exit_code.value_or(1)) +
+                                             "; see job log"}});
                     throw std::runtime_error("Process exited with code " +
                                              std::to_string(poll.exit_code.value_or(1)) +
                                              "; see job log");
+                }
                 return output;
             }
             std::this_thread::sleep_for(std::chrono::milliseconds(15));
@@ -240,19 +391,23 @@ struct BuildService::Impl {
         }
     }
     Json build(Job& job, bool exporting = false) {
+        const auto started = std::chrono::steady_clock::now();
+        const auto milliseconds = [](auto from, auto to) {
+            return std::chrono::duration_cast<std::chrono::milliseconds>(to - from).count();
+        };
         const auto& configuration = exporting ? config.export_configuration : config.configuration;
         const auto native_directory = config.build_directory / configuration;
         checkpoint(job, "Configuring gameplay", .05);
         job.lua = scripting::loadLuaProject(config.project_root);
-        const auto cpp = config.project_root / "Scripts" / "Gameplay.cpp";
-        const auto hpp = config.project_root / "Scripts" / "Gameplay.hpp";
+        const auto inputs = capture_build_inputs(config, job.lua);
+        const auto staged_scripts = stage_gameplay_sources(config, inputs, job.lua, job.status.id);
+        const auto cpp = staged_scripts / "Gameplay.cpp";
+        const auto hpp = staged_scripts / "Gameplay.hpp";
         const bool has_cpp = fs::is_regular_file(cpp), has_hpp = fs::is_regular_file(hpp);
         if (has_cpp != has_hpp || (!has_cpp && !job.lua.enabled()))
             throw std::runtime_error("Project requires Scripts/Gameplay.cpp and Gameplay.hpp, "
                                      "or Lua entry scripts declared in project.faset.json");
-        const auto cpp_source = has_cpp ? read_text(cpp) : std::string{};
-        const auto hpp_source = has_hpp ? read_text(hpp) : std::string{};
-        fs::create_directories(native_directory);
+        ensure_native_toolchain_stamp(config, native_directory, inputs);
         std::vector<std::string> arguments = {config.cmake,
                                               "-S",
                                               path_to_utf8(config.engine_root),
@@ -267,37 +422,100 @@ struct BuildService::Impl {
                                               "-DFASET_BUILD_RUNTIME=ON",
                                               "-DFASET_BUILD_ASSETS=ON",
                                               "-DFASET_GAMEPLAY_SOURCE_DIR=" +
-                                                  path_to_utf8(config.project_root / "Scripts")};
-        bool compiler_overridden = false;
-        for (const auto& arg : config.configure_arguments)
-            if (arg.starts_with("-DCMAKE_CXX_COMPILER="))
-                compiler_overridden = true;
-        if (!compiler_overridden) {
+                                                  path_to_utf8(staged_scripts)};
+        if (!configured_cmake_value(config, "CMAKE_C_COMPILER")) {
 #ifdef _WIN32
             auto compiler = find_executable("clang-cl");
             arguments.push_back("-DCMAKE_C_COMPILER=" + path_to_utf8(compiler));
-            arguments.push_back("-DCMAKE_CXX_COMPILER=" + path_to_utf8(compiler));
 #else
             arguments.push_back("-DCMAKE_C_COMPILER=" + path_to_utf8(find_executable("clang")));
+#endif
+        }
+        if (!configured_cmake_value(config, "CMAKE_CXX_COMPILER")) {
+#ifdef _WIN32
+            arguments.push_back("-DCMAKE_CXX_COMPILER=" +
+                                path_to_utf8(find_executable("clang-cl")));
+#else
             arguments.push_back("-DCMAKE_CXX_COMPILER=" + path_to_utf8(find_executable("clang++")));
 #endif
         }
-        arguments.insert(arguments.end(), config.configure_arguments.begin(),
-                         config.configure_arguments.end());
+        for (const auto& argument : config.configure_arguments) {
+            const auto equal = argument.find('=');
+            const auto colon = argument.find(':', 2);
+            const auto key = argument.substr(2, colon < equal ? colon - 2 : equal - 2);
+            if (key == "CMAKE_C_COMPILER" || key == "CMAKE_CXX_COMPILER" ||
+                key == "SLANGC_EXECUTABLE" || key == "CMAKE_TOOLCHAIN_FILE") {
+                const auto value = path_from_utf8(argument.substr(equal + 1));
+                if (value.has_parent_path() && value.is_relative()) {
+                    arguments.push_back(argument.substr(0, equal + 1) +
+                                        path_to_utf8((config.project_root / value).lexically_normal()));
+                    continue;
+                }
+            }
+            arguments.push_back(argument);
+        }
         arguments.push_back("-DCMAKE_BUILD_TYPE=" + configuration);
         // Project declarations, not a stale cache or a user-supplied override, determine
         // whether the packaged game has a Lua VM linked into it.
         arguments.push_back(std::string("-DFASET_ENABLE_LUA=") +
                             (job.lua.enabled() ? "ON" : "OFF"));
         run(job, std::move(arguments), config.project_root);
+        const auto configured = std::chrono::steady_clock::now();
         checkpoint(job, "Compiling and linking Player", .25);
         run(job,
             {config.cmake, "--build", path_to_utf8(native_directory), "--config", configuration,
              "--parallel", "4", "--target", "faset_player", "faset_schema_exporter"},
             config.project_root);
-        checkpoint(job, "Exporting gameplay schema", .58);
+        const auto compiled = std::chrono::steady_clock::now();
         auto player = build_executable(native_directory, configuration, "faset_player");
         auto exporter = build_executable(native_directory, configuration, "faset_schema_exporter");
+        const auto package_key =
+            build_package_key(inputs, native_directory, configuration, player, exporter);
+        const auto source_unchanged = [&] {
+            if (gameplay_source_hash(config.project_root,
+                                     scripting::loadLuaProject(config.project_root)) !=
+                inputs.source_hash)
+                throw std::runtime_error("Gameplay sources changed during the build; build again");
+        };
+        const auto result_for = [&](const std::string& id, const std::string& fingerprint,
+                                    bool reused) -> Json {
+            const auto directory = config.cache_root / "builds" / id;
+            const auto finished = std::chrono::steady_clock::now();
+            return {{"generation", id},
+                    {"directory", path_to_utf8(directory)},
+                    {"build_directory", path_to_utf8(native_directory)},
+                    {"configuration", configuration},
+                    {"player", path_to_utf8(directory / ("faset_player" + executable_suffix()))},
+                    {"schema", path_to_utf8(directory / "schema.json")},
+                    {"lua_enabled", job.lua.enabled()},
+                    {"lua_fingerprint", job.lua.fingerprint},
+                    {"fingerprint", fingerprint},
+                    {"schema_cache_hit", reused},
+                    {"generation_reused", reused},
+                    {"phase_times_ms",
+                     {{"configure", milliseconds(started, configured)},
+                      {"native_build", milliseconds(configured, compiled)},
+                      {"schema_package", reused ? 0 : milliseconds(compiled, finished)},
+                      {"total", milliseconds(started, finished)}}}};
+        };
+        const auto pointer_file = config.cache_root / "last_build.json";
+        if (fs::is_regular_file(pointer_file))
+            try {
+                const auto pointer = read_json(pointer_file);
+                const auto id = pointer.at("generation").get<std::string>();
+                const auto candidate =
+                    project_path(config.cache_root, fs::path("builds") / id);
+                if (validate_build_generation(candidate, package_key)) {
+                    source_unchanged();
+                    checkpoint(job, "Reusing verified build generation", .68);
+                    const auto manifest = read_json(candidate / "manifest.json");
+                    log(job, "Verified schema/package cache hit: " + id + "\n");
+                    return result_for(id, manifest.at("fingerprint").get<std::string>(), true);
+                }
+            } catch (const std::exception&) {
+                // A bad pointer or old/corrupt generation is a cache miss.
+            }
+        checkpoint(job, "Exporting gameplay schema", .58);
         const auto staging = config.cache_root / "builds" / (".staging-" + job.status.id);
         const auto generation = config.cache_root / "builds" / job.status.id;
         fs::create_directories(staging);
@@ -322,10 +540,7 @@ struct BuildService::Impl {
             // Validate the complete metadata before publishing either the schema or
             // its Player generation. Session uses this same authoring contract.
             (void)authoring::gameplay_schemas(schema);
-            std::string fingerprint = sha256_file(player) + sha256_file(exporter) +
-                                      read_text(native_directory / "CMakeCache.txt");
-            fingerprint += cpp_source + hpp_source + job.lua.fingerprint;
-            fingerprint = sha256(fingerprint);
+            const auto fingerprint = package_key;
             schema["build_fingerprint"] = fingerprint;
             if (job.lua.enabled())
                 schema["lua_fingerprint"] = job.lua.fingerprint;
@@ -341,36 +556,39 @@ struct BuildService::Impl {
                                      "gpuHzbMain.reflection.json", "gpuPostCullMain.reflection.json"})
                 copy_required_file(native_directory / "shaders" / file, staging / "shaders" / file);
             copy_runtime_libraries(job, player, staging, native_directory, configuration);
+            Json files = Json::array();
+            for (const auto& entry : fs::recursive_directory_iterator(staging)) {
+                if (entry.is_symlink())
+                    throw std::runtime_error("Build generation contains a symlink");
+                if (entry.is_regular_file())
+                    files.push_back(
+                        {{"path", generic_path_to_utf8(entry.path().lexically_relative(staging))},
+                         {"sha256", sha256_file(entry.path())},
+                         {"size", entry.file_size()}});
+            }
             Json manifest{{"format", "faset.build"},
-                          {"version", 1},
+                          {"version", 2},
                           {"id", job.status.id},
                           {"fingerprint", fingerprint},
+                          {"package_key", package_key},
                           {"configuration", configuration},
                           {"lua_enabled", job.lua.enabled()},
                           {"lua_fingerprint", job.lua.fingerprint},
                           {"player", "faset_player" + executable_suffix()},
-                          {"schema", "schema.json"}};
+                          {"schema", "schema.json"},
+                          {"files", files}};
             atomic_write_json(staging / "manifest.json", manifest);
             checkpoint(job, "Publishing build generation", .68);
             if (job.lua.enabled() &&
                 scripting::loadLuaProject(staging).fingerprint != job.lua.fingerprint)
                 throw std::runtime_error("Lua build snapshot changed during schema export");
-            if (scripting::loadLuaProject(config.project_root).fingerprint != job.lua.fingerprint ||
-                has_cpp != fs::is_regular_file(cpp) || has_hpp != fs::is_regular_file(hpp) ||
-                (has_cpp && (read_text(cpp) != cpp_source || read_text(hpp) != hpp_source)))
-                throw std::runtime_error("Gameplay sources changed during the build; build again");
+            source_unchanged();
+            if (!validate_build_generation(staging, package_key))
+                throw std::runtime_error("Build generation failed final integrity validation");
             fs::rename(staging, generation);
             atomic_write_json(config.cache_root / "last_build.json",
                               {{"generation", job.status.id}, {"fingerprint", fingerprint}});
-            return {{"generation", job.status.id},
-                    {"directory", path_to_utf8(generation)},
-                    {"build_directory", path_to_utf8(native_directory)},
-                    {"configuration", configuration},
-                    {"player", path_to_utf8(generation / ("faset_player" + executable_suffix()))},
-                    {"schema", path_to_utf8(generation / "schema.json")},
-                    {"lua_enabled", job.lua.enabled()},
-                    {"lua_fingerprint", job.lua.fingerprint},
-                    {"fingerprint", fingerprint}};
+            return result_for(job.status.id, fingerprint, false);
         } catch (...) {
             std::error_code error;
             fs::remove_all(staging, error);
@@ -785,6 +1003,97 @@ void BuildService::scaffold(const std::string& name, int dimension) {
     if (!fs::exists(c.project_root / ".gitignore"))
         atomic_write(c.project_root / ".gitignore", ".faset/\nExports/\n");
 }
+void BuildService::scaffold(const std::string& name, int dimension,
+                            std::string_view language) {
+    if (name.empty() || (dimension != 2 && dimension != 3) ||
+        (language != "cpp" && language != "lua"))
+        throw std::invalid_argument("Starter requires a name, 2D/3D and cpp/lua language");
+    const auto& c = impl_->config;
+    StarterCreateLock lock(c.project_root);
+    require_new_starter_directory(c.project_root);
+    const auto scene = starter_scene(name, dimension, language);
+    const auto source = c.engine_root / "tools/project_templates" /
+                        (language == "lua" ? "lua-main.lua" : "Gameplay.cpp");
+    const auto module = read_text(source);
+    const auto header = language == "cpp"
+                            ? read_text(c.engine_root / "tools/project_templates/Gameplay.hpp")
+                            : std::string();
+    const auto lua_annotations = language == "lua"
+                                     ? read_text(c.engine_root / "tools/lua/faset.lua")
+                                     : std::string();
+    const auto lua_config = language == "lua"
+                                ? read_json(c.engine_root / "tools/lua/luarc.json")
+                                : Json();
+    const auto lua_scripts_config =
+        language == "lua" ? read_json(c.engine_root / "tools/lua/luarc-scripts.json") : Json();
+    const auto stage = lock.path / "staged";
+    fs::create_directories(stage / "Scripts");
+    fs::create_directories(stage / "Scenes");
+    fs::create_directories(stage / "Assets");
+    if (language == "cpp") {
+        atomic_write(stage / "Scripts/Gameplay.cpp", module);
+        atomic_write(stage / "Scripts/Gameplay.hpp", header);
+    } else {
+        atomic_write(stage / "Scripts/main.lua", module);
+        atomic_write(stage / ".faset/lua/faset.lua", lua_annotations);
+        atomic_write_json(stage / ".luarc.json", lua_config);
+        atomic_write_json(stage / "Scripts/.luarc.json", lua_scripts_config);
+    }
+    atomic_write_json(stage / "Scenes/main.scene.json", scene);
+    Json project = {{"format", "faset.project"},
+                    {"version", 1},
+                    {"id", new_id()},
+                    {"name", name},
+                    {"dimension", dimension},
+                    {"start_scene", "Scenes/main.scene.json"}};
+    if (language == "lua")
+        project["scripting"] = {{"lua", {{"scripts", Json::array({"Scripts/main.lua"})}}}};
+    atomic_write_json(stage / "project.faset.json", project);
+    atomic_write(stage / ".gitignore",
+                 ".faset/*\n!.faset/lua/\n.faset/lua/*\n!.faset/lua/faset.lua\nExports/\n");
+    std::vector<std::pair<fs::path, std::string>> created;
+    auto publish = [&](const fs::path& relative) {
+        const auto source = stage / relative;
+        const auto target = c.project_root / relative;
+        fs::create_directories(target.parent_path());
+        if (!fs::copy_file(source, target, fs::copy_options::none))
+            throw std::runtime_error("Starter destination appeared during creation: " +
+                                     path_to_utf8(target));
+        created.emplace_back(target, sha256_file(source));
+    };
+    try {
+        publish(".gitignore");
+        if (language == "cpp") {
+            publish("Scripts/Gameplay.cpp");
+            publish("Scripts/Gameplay.hpp");
+        } else {
+            publish("Scripts/main.lua");
+            publish(".faset/lua/faset.lua");
+            publish(".luarc.json");
+            publish("Scripts/.luarc.json");
+        }
+        publish("Scenes/main.scene.json");
+        fs::create_directory(c.project_root / "Assets");
+        // The manifest is the final commit marker: an interrupted create has no
+        // valid project record and never replaces an existing project file.
+        publish("project.faset.json");
+    } catch (...) {
+        for (auto it = created.rbegin(); it != created.rend(); ++it) {
+            try {
+                std::error_code ignored;
+                if (fs::is_regular_file(it->first, ignored) &&
+                    sha256_file(it->first) == it->second)
+                    fs::remove(it->first, ignored);
+            } catch (...) { /* Preserve the original create failure. */
+            }
+        }
+        for (const auto& relative : {"Assets", "Scenes", "Scripts", ".faset/lua"}) {
+            std::error_code ignored;
+            fs::remove(c.project_root / relative, ignored); // Empty directories only.
+        }
+        throw;
+    }
+}
 std::string BuildService::start_build() {
     return impl_->enqueue("build");
 }

src/editor/session.cpp

@@ -2,6 +2,7 @@
 #include <chrono>
 #include <faset/core/hash.hpp>
 #include <faset/core/io.hpp>
+#include <faset/editor/build_cache.hpp>
 #include <faset/editor/session.hpp>
 #include <faset/scripting/project.hpp>
 
@@ -112,6 +113,10 @@ void Session::scaffold(const std::string& name, int dimension) {
     builds_.scaffold(name, dimension);
     log("Created project: " + name);
 }
+void Session::scaffold(const std::string& name, int dimension, std::string_view language) {
+    builds_.scaffold(name, dimension, language);
+    log("Created " + std::string(language) + " starter project: " + name);
+}
 Json Session::assets_list() const {
     Json list = Json::array();
     const auto directory = assets_.cache_root() / "assets";
@@ -132,20 +137,7 @@ Json Session::assets_list() const {
 }
 std::string Session::source_signature() const {
     const auto lua = scripting::loadLuaProject(config_.project_root);
-    const auto directory = config_.project_root / "Scripts";
-    std::vector<std::filesystem::path> files;
-    if (std::filesystem::exists(directory))
-        for (const auto& file : std::filesystem::recursive_directory_iterator(directory))
-            if (file.is_regular_file() && (!lua.enabled() || file.path().extension() != ".lua"))
-                files.push_back(file.path());
-    std::sort(files.begin(), files.end());
-    std::string contents;
-    for (const auto& file : files)
-        contents += generic_path_to_utf8(file.lexically_relative(directory)) + ":" +
-                    sha256_file(file) + "\n";
-    if (lua.enabled())
-        contents += "lua:" + lua.fingerprint + "\n";
-    return sha256(contents);
+    return gameplay_source_hash(config_.project_root, lua);
 }
 Json Session::schema_status() const {
     try {
@@ -514,51 +506,102 @@ void Session::register_commands() {
                         {"configuration_created", create_configuration},
                         {"scripts_configuration_created", create_scripts_configuration}};
         });
-    commands_.add(
-        "faset_script_open",
-        "Open a project Lua source in an external editor, never as an executable. Optional editor "
-        "is an argv array (default: project editor.script_editor, then zed). Exact {file} and "
-        "{project} arguments are replaced; no shell expansion is performed.",
-        schema({{"path", text}, {"editor", {{"type", "array"}, {"items", text}, {"minItems", 1}}}},
-               {"path"}),
-        [&](const Json& args) {
-            const auto file = project_path(config_.project_root,
-                                           path_from_utf8(args.at("path").get<std::string>()));
-            require(file.extension() == ".lua" && std::filesystem::is_regular_file(file),
-                    "lua.source", "Select an existing .lua file inside the project");
-            Json command = Json::array({"zed", "{file}"});
-            const auto settings = project();
-            if (settings.contains("editor") && settings.at("editor").is_object() &&
-                settings.at("editor").contains("script_editor"))
-                command = settings.at("editor").at("script_editor");
-            if (args.contains("editor"))
-                command = args.at("editor");
-            require(command.is_array() && !command.empty(), "lua.editor",
-                    "Configure editor.script_editor as a nonempty executable/argument array");
-            std::vector<std::string> arguments;
-            bool has_file = false;
-            for (const auto& part : command) {
-                require(part.is_string(), "lua.editor", "Editor arguments must be strings");
-                auto argument = part.get<std::string>();
-                require(argument.find('\0') == std::string::npos, "lua.editor",
-                        "Editor arguments cannot contain NUL");
-                if (argument == "{file}") {
-                    require(!arguments.empty(), "lua.editor", "The first argument is the editor");
-                    argument = path_to_utf8(file);
-                    has_file = true;
-                } else if (argument == "{project}") {
-                    require(!arguments.empty(), "lua.editor", "The first argument is the editor");
-                    argument = path_to_utf8(std::filesystem::absolute(config_.project_root));
-                }
-                arguments.push_back(std::move(argument));
+    const auto open_source = [this](const Json& args, bool lua_only) -> Json {
+        const auto path_error = lua_only ? "lua.source" : "source.path";
+        const auto editor_error = lua_only ? "lua.editor" : "source.editor";
+        const auto requested = path_from_utf8(args.at("path").get<std::string>());
+        require(!requested.empty() && !requested.is_absolute(), path_error,
+                "Choose an existing source inside Scripts");
+        for (const auto& part : requested)
+            require(part != "..", path_error, "Source path cannot traverse outside Scripts");
+        std::filesystem::path file;
+        try {
+            file = project_path(config_.project_root, requested);
+        } catch (const std::exception&) {
+            throw Error(path_error, "Source path must stay inside project Scripts");
+        }
+        const auto project_root = std::filesystem::weakly_canonical(config_.project_root);
+        const auto relative = file.lexically_relative(project_root);
+        const auto name = generic_path_to_utf8(relative);
+        const auto extension = path_to_utf8(file.extension());
+        const bool supported = extension == ".cpp" || extension == ".hpp" ||
+                               extension == ".h" || extension == ".cc" ||
+                               extension == ".cxx" || extension == ".lua";
+        require(name.starts_with("Scripts/") && supported &&
+                    (!lua_only || extension == ".lua") &&
+                    std::filesystem::is_regular_file(file),
+                path_error, "Choose an existing source file inside Scripts");
+        const auto line = args.value("line", 1);
+        const auto column = args.value("column", 1);
+        require(line > 0 && column > 0, path_error, "Source line and column must be positive");
+        Json command = Json::array({"zed", "{file}:{line}:{column}"});
+        const auto settings = project();
+        if (settings.contains("editor") && settings.at("editor").is_object() &&
+            settings.at("editor").contains("script_editor"))
+            command = settings.at("editor").at("script_editor");
+        if (args.contains("editor"))
+            command = args.at("editor");
+        require(command.is_array() && !command.empty(), editor_error,
+                "Configure editor.script_editor as a nonempty executable/argument array");
+        auto replace = [](std::string& target, std::string_view token,
+                          const std::string& replacement) {
+            bool found = false;
+            std::size_t position = 0;
+            while ((position = target.find(token, position)) != std::string::npos) {
+                target.replace(position, token.size(), replacement);
+                position += replacement.size();
+                found = true;
             }
-            require(!arguments.front().empty(), "lua.editor", "Choose an editor executable");
-            if (!has_file)
-                arguments.push_back(path_to_utf8(file));
+            return found;
+        };
+        std::vector<std::string> arguments;
+        bool has_file = false;
+        for (const auto& part : command) {
+            require(part.is_string(), editor_error, "Editor arguments must be strings");
+            auto argument = part.get<std::string>();
+            require(argument.find('\0') == std::string::npos, editor_error,
+                    "Editor arguments cannot contain NUL");
+            if (arguments.empty())
+                require(!argument.empty() && argument.find('{') == std::string::npos,
+                        editor_error, "The first argument must be an editor executable");
+            else {
+                has_file |= replace(argument, "{file}", path_to_utf8(file));
+                replace(argument, "{line}", std::to_string(line));
+                replace(argument, "{column}", std::to_string(column));
+                replace(argument, "{project}", path_to_utf8(project_root));
+            }
+            arguments.push_back(std::move(argument));
+        }
+        if (!has_file)
+            arguments.push_back(path_to_utf8(file));
+        try {
             launch_detached(arguments, config_.project_root);
-            log("Opened Lua source in external editor: " + args.at("path").get<std::string>());
-            return Json{{"opened", args.at("path")}};
-        });
+        } catch (const std::exception& error) {
+            throw Error(editor_error, "Could not launch external source editor",
+                        {{"reason", error.what()}});
+        }
+        log("Opened source in external editor: " + name);
+        return {{"opened", name}, {"path", name}, {"line", line}, {"column", column}};
+    };
+    const auto source_schema = schema(
+        {{"path", text},
+         {"line", {{"type", "integer"}, {"minimum", 1}}},
+         {"column", {{"type", "integer"}, {"minimum", 1}}},
+         {"editor", {{"type", "array"}, {"items", text}, {"minItems", 1}}}},
+        {"path"});
+    commands_.add("faset_source_open",
+                  "Open a C++ or Lua source under Scripts at a one-based line and column. "
+                  "The editor is an argv array; {file}, {line}, {column} and {project} are "
+                  "substituted without a shell.",
+                  source_schema, [open_source](const Json& args) {
+                      return open_source(args, false);
+                  });
+    commands_.add("faset_script_open",
+                  "Open a project Lua source in an external editor. This compatibility command "
+                  "retains Lua-only validation and uses the same safe source launcher.",
+                  source_schema, [open_source](const Json& args) {
+                      return open_source(args, true);
+                  });
     commands_.add("faset_export",
                   "Build, validate and export a resolved authoring snapshot to a project-relative "
                   "output directory. Returns a job ID.",

src/player/SceneView.cpp

@@ -61,16 +61,6 @@ render::Vec3 direction(const render::Mat4& m, render::Vec3 p) {
     return {m[0] * p[0] + m[4] * p[1] + m[8] * p[2], m[1] * p[0] + m[5] * p[1] + m[9] * p[2],
             m[2] * p[0] + m[6] * p[1] + m[10] * p[2]};
 }
-render::Vec3 normalized(render::Vec3 value, const std::string& entityId,
-                        std::string_view field) {
-    const auto length = std::hypot(value[0], value[1], value[2]);
-    if (!std::isfinite(length) || length < 1e-6f)
-        throw std::invalid_argument("Light on entity " + entityId + " has invalid " +
-                                    std::string(field));
-    for (auto& axis : value)
-        axis /= length;
-    return value;
-}
 std::pair<std::string, std::string> reference(const std::string& ref) {
     const auto hash = ref.find('#');
     return {ref.substr(0, hash), hash == std::string::npos ? std::string{} : ref.substr(hash + 1)};
@@ -273,12 +263,8 @@ render::Snapshot SceneView::build(const Json& scene, float aspect, CameraSetting
         const auto id = entity.at("id").get<std::string>();
         if (!byId.emplace(id, &entity).second)
             throw std::invalid_argument("Duplicate scene ID");
-        if (!entity.contains("components") && entity.contains("light"))
-            out.authored_lights_present = true;
         for (const auto& component : entity.value("components", Json::array())) {
             const auto type = component.at("type").get<std::string>();
-            if (type == "faset.light")
-                out.authored_lights_present = true;
             if (component.value("version", 1) != 1 &&
                 (type == "faset.transform" || type == "faset.sprite" || type == "faset.mesh" ||
                  type == "faset.camera" || type == "faset.light"))
@@ -315,15 +301,8 @@ render::Snapshot SceneView::build(const Json& scene, float aspect, CameraSetting
     render::Vec3 cameraUp{0, 1, 0};
     bool foundCamera = false;
     std::vector<std::pair<int, render::Sprite>> sprites;
-    std::vector<render::SunLight> directionalLights;
     for (const auto& entity : entities) {
-        const auto id = entity.at("id").get<std::string>();
-        render::Mat4 model;
-        try {
-            model = world(world, entity);
-        } catch (const std::exception& error) {
-            throw std::invalid_argument("Entity " + id + " transform: " + error.what());
-        }
+        const auto model = world(world, entity);
         if (auto fields = properties(entity, "camera");
             !fields.is_null() && !camera.overrideSceneCamera && !foundCamera) {
             camera.eye = point(model, {0, 0, 0});
@@ -335,97 +314,8 @@ render::Snapshot SceneView::build(const Json& scene, float aspect, CameraSetting
             foundCamera = true;
             camera_id = entity.at("id").get<std::string>();
         }
-        if (auto fields = properties(entity, "light"); !fields.is_null()) {
-            auto invalid = [&](std::string_view field) -> void {
-                throw std::invalid_argument("Light on entity " + id + " has invalid " +
-                                            std::string(field));
-            };
-            for (const auto entry : model)
-                if (!std::isfinite(entry))
-                    invalid("transform");
-            auto number = [&](const char* field, float fallback) {
-                if (!fields.contains(field))
-                    return fallback;
-                const auto& value = fields.at(field);
-                if (!value.is_number())
-                    invalid(field);
-                const auto decimal = value.get<double>();
-                if (!std::isfinite(decimal) ||
-                    std::abs(decimal) > std::numeric_limits<float>::max())
-                    invalid(field);
-                return static_cast<float>(decimal);
-            };
-            auto boolean = [&](const char* field, bool fallback) {
-                if (!fields.contains(field))
-                    return fallback;
-                if (!fields.at(field).is_boolean())
-                    invalid(field);
-                return fields.at(field).get<bool>();
-            };
-            const auto enabled = boolean("enabled", true);
-            if (enabled) {
-                if (fields.contains("kind") && !fields.at("kind").is_string())
-                    invalid("kind");
-                const auto kind = fields.value("kind", std::string("directional"));
-                if (kind != "directional" && kind != "point" && kind != "spot")
-                    invalid("kind");
-                render::Color color;
-                try {
-                    color = vec<4>(fields, "color", {1, 1, 1, 1});
-                } catch (const std::exception&) {
-                    invalid("color");
-                }
-                for (const auto channel : color)
-                    if (channel < 0)
-                        invalid("color");
-                const auto intensity = number("intensity", 1);
-                if (intensity < 0)
-                    invalid("intensity");
-                const auto castsShadow = boolean("casts_shadow", true);
-                const auto stableId = id;
-                if (kind == "directional") {
-                    directionalLights.push_back({stableId,
-                                                 normalized(direction(model, {-0.5f, -1, -0.3f}), id,
-                                                            "direction"),
-                                                 color, intensity, castsShadow});
-                } else {
-                    render::LocalLight local;
-                    local.kind = kind == "point" ? render::LocalLight::Kind::Point
-                                                 : render::LocalLight::Kind::Spot;
-                    local.stable_id = stableId;
-                    local.position = point(model, {0, 0, 0});
-                    for (const auto coordinate : local.position)
-                        if (!std::isfinite(coordinate))
-                            invalid("position");
-                    if (local.kind == render::LocalLight::Kind::Spot)
-                        local.direction = normalized(direction(model, {0, 0, -1}), id,
-                                                     "direction");
-                    local.color = color;
-                    local.intensity = intensity;
-                    local.range = number("range", 10);
-                    if (local.range <= 0)
-                        invalid("range");
-                    local.inner_angle = number("inner_angle", 0.35f);
-                    local.outer_angle = number("outer_angle", 0.7f);
-                    if (local.kind == render::LocalLight::Kind::Spot &&
-                        (local.inner_angle < 0 || local.inner_angle > local.outer_angle ||
-                         local.outer_angle <= 0 ||
-                         local.outer_angle >= std::numbers::pi_v<float> / 2))
-                        invalid("inner_angle/outer_angle");
-                    local.casts_shadow = castsShadow;
-                    if (fields.contains("shadow_priority")) {
-                        if (!fields.at("shadow_priority").is_number_integer())
-                            invalid("shadow_priority");
-                        const auto priority = fields.at("shadow_priority").get<double>();
-                        if (priority < std::numeric_limits<int>::min() ||
-                            priority > std::numeric_limits<int>::max())
-                            invalid("shadow_priority");
-                        local.shadow_priority = fields.at("shadow_priority").get<int>();
-                    }
-                    out.local_lights.push_back(std::move(local));
-                }
-            }
-        }
+        if (auto fields = properties(entity, "light"); !fields.is_null())
+            out.light_direction = direction(model, {-0.5f, -1, -0.3f});
         if (auto fields = properties(entity, "sprite"); !fields.is_null()) {
             render::Sprite sprite;
             sprite.layer = fields.value("layer", 0);
@@ -482,18 +372,6 @@ render::Snapshot SceneView::build(const Json& scene, float aspect, CameraSetting
                      [](const auto& a, const auto& b) { return a.first < b.first; });
     for (auto& pair : sprites)
         out.sprites.push_back(std::move(pair.second));
-    std::sort(directionalLights.begin(), directionalLights.end(),
-              [](const auto& a, const auto& b) { return a.stable_id < b.stable_id; });
-    std::sort(out.local_lights.begin(), out.local_lights.end(),
-              [](const auto& a, const auto& b) { return a.stable_id < b.stable_id; });
-    if (!directionalLights.empty()) {
-        out.sun = directionalLights.front();
-        out.light_direction = out.sun->direction;
-        if (directionalLights.size() > 1)
-            impl_->messages.push_back("warning: multiple enabled directional lights; using " +
-                                      out.sun->stable_id + " and ignoring " +
-                                      std::to_string(directionalLights.size() - 1) + " others");
-    }
     if (dimension == 2) {
         const float height = camera.orthographicHeight;
         if (!std::isfinite(height) || height <= 0)
@@ -530,10 +408,8 @@ render::Snapshot SceneView::build(const Json& scene, float aspect, CameraSetting
         out.projection = render::perspective(
             camera.verticalFovDegrees * std::numbers::pi_v<float> / 180, aspect,
             camera.nearPlane, camera.farPlane);
-        const auto view = render::look_at(camera.eye, camera.target, cameraUp);
-        out.view_projection = render::multiply(out.projection, view);
-        out.camera_frustum = render::CameraFrustum{view, out.projection, camera.nearPlane,
-                                                   camera.farPlane, true};
+        out.view_projection = render::multiply(
+            out.projection, render::look_at(camera.eye, camera.target, cameraUp));
     }
     std::sort(impl_->messages.begin(), impl_->messages.end());
     impl_->messages.erase(std::unique(impl_->messages.begin(), impl_->messages.end()),

src/render/lighting.cpp

@@ -1,392 +0,0 @@
-#include <faset/render/lighting.hpp>
-#include <algorithm>
-#include <array>
-#include <cmath>
-#include <limits>
-#include <numbers>
-#include <stdexcept>
-#include <unordered_set>
-
-namespace faset::render {
-namespace {
-Vec3 add(Vec3 a, Vec3 b) { return {a[0] + b[0], a[1] + b[1], a[2] + b[2]}; }
-Vec3 subtract(Vec3 a, Vec3 b) { return {a[0] - b[0], a[1] - b[1], a[2] - b[2]}; }
-Vec3 scale(Vec3 a, float factor) { return {a[0] * factor, a[1] * factor, a[2] * factor}; }
-float dot(Vec3 a, Vec3 b) { return a[0] * b[0] + a[1] * b[1] + a[2] * b[2]; }
-float length(Vec3 a) { return std::sqrt(dot(a, a)); }
-Vec3 unit(Vec3 a) {
-    const float magnitude = length(a);
-    if (!std::isfinite(magnitude) || magnitude < 1e-6f)
-        throw std::invalid_argument("Shadow light direction must be finite and nonzero");
-    return scale(a, 1.f / magnitude);
-}
-Vec3 project(const Mat4& matrix, Vec3 value) {
-    return {matrix[0] * value[0] + matrix[4] * value[1] + matrix[8] * value[2] + matrix[12],
-            matrix[1] * value[0] + matrix[5] * value[1] + matrix[9] * value[2] + matrix[13],
-            matrix[2] * value[0] + matrix[6] * value[1] + matrix[10] * value[2] + matrix[14]};
-}
-std::array<float, 4> clip(const Mat4& matrix, Vec3 value) {
-    return {matrix[0] * value[0] + matrix[4] * value[1] + matrix[8] * value[2] + matrix[12],
-            matrix[1] * value[0] + matrix[5] * value[1] + matrix[9] * value[2] + matrix[13],
-            matrix[2] * value[0] + matrix[6] * value[1] + matrix[10] * value[2] + matrix[14],
-            matrix[3] * value[0] + matrix[7] * value[1] + matrix[11] * value[2] + matrix[15]};
-}
-std::array<Vec3, 8> corners(const Bounds& bounds) {
-    std::array<Vec3, 8> result{};
-    for (unsigned i = 0; i < 8; ++i)
-        result[i] = {i & 1 ? bounds.max[0] : bounds.min[0],
-                     i & 2 ? bounds.max[1] : bounds.min[1],
-                     i & 4 ? bounds.max[2] : bounds.min[2]};
-    return result;
-}
-Vec3 camera_to_world(const Mat4& view, Vec3 camera) {
-    // CameraFrustum::view is an unscaled, orthonormal look_at matrix.
-    return {view[0] * (camera[0] - view[12]) + view[1] * (camera[1] - view[13]) +
-                view[2] * (camera[2] - view[14]),
-            view[4] * (camera[0] - view[12]) + view[5] * (camera[1] - view[13]) +
-                view[6] * (camera[2] - view[14]),
-            view[8] * (camera[0] - view[12]) + view[9] * (camera[1] - view[13]) +
-                view[10] * (camera[2] - view[14])};
-}
-std::array<Vec3, 8> frustum_slice(const CameraFrustum& camera, float near_distance,
-                                  float far_distance) {
-    std::array<Vec3, 8> result{};
-    for (unsigned i = 0; i < 8; ++i) {
-        const float distance = i & 4 ? far_distance : near_distance;
-        const float x = i & 1 ? 1.f : -1.f;
-        const float y = i & 2 ? 1.f : -1.f;
-        Vec3 local{};
-        if (camera.perspective)
-            local = {x * distance / camera.projection[0],
-                     y * distance / camera.projection[5], -distance};
-        else
-            local = {(x - camera.projection[12]) / camera.projection[0],
-                     (y - camera.projection[13]) / camera.projection[5], -distance};
-        result[i] = camera_to_world(camera.view, local);
-    }
-    return result;
-}
-bool overlaps_xy(const Bounds& bounds, const Mat4& light_view, float left, float right,
-                 float bottom, float top) {
-    float min_x = std::numeric_limits<float>::infinity();
-    float max_x = -min_x, min_y = min_x, max_y = -min_x;
-    for (const auto point : corners(bounds)) {
-        const auto light = project(light_view, point);
-        min_x = std::min(min_x, light[0]);
-        max_x = std::max(max_x, light[0]);
-        min_y = std::min(min_y, light[1]);
-        max_y = std::max(max_y, light[1]);
-    }
-    return max_x >= left && min_x <= right && max_y >= bottom && min_y <= top;
-}
-bool intersects_frustum(const Bounds& bounds, const Mat4& view_projection) {
-    std::array<unsigned, 7> rejected{};
-    for (const auto point : corners(bounds)) {
-        const auto p = clip(view_projection, point);
-        if (!std::all_of(p.begin(), p.end(), [](float value) { return std::isfinite(value); }))
-            return true; // Invalid projection fails open so no caster is lost silently.
-        rejected[0] += p[0] < -p[3];
-        rejected[1] += p[0] > p[3];
-        rejected[2] += p[1] < -p[3];
-        rejected[3] += p[1] > p[3];
-        rejected[4] += p[2] < 0;
-        rejected[5] += p[2] > p[3];
-        rejected[6] += p[3] <= 0;
-    }
-    return std::none_of(rejected.begin(), rejected.end(), [](unsigned count) { return count == 8; });
-}
-void tile(ShadowView& view, std::uint32_t atlas_size, std::uint32_t tiles_across,
-          std::uint32_t index) {
-    constexpr std::uint32_t guard = 2;
-    const auto size = atlas_size / tiles_across;
-    view.tile_index = index;
-    view.tile_origin_x = (index % tiles_across) * size;
-    view.tile_origin_y = (index / tiles_across) * size;
-    view.tile_size = size;
-    view.usable_size = size - 2 * guard;
-    const auto reciprocal = 1.f / float(atlas_size);
-    view.atlas_scale_offset = {float(view.usable_size) * reciprocal,
-                               float(view.usable_size) * reciprocal,
-                               float(view.tile_origin_x + guard) * reciprocal,
-                               float(view.tile_origin_y + guard) * reciprocal};
-    view.guarded_clamp = {(float(view.tile_origin_x + guard) + 1.5f) * reciprocal,
-                          (float(view.tile_origin_y + guard) + 1.5f) * reciprocal,
-                          (float(view.tile_origin_x + size - guard) - 1.5f) * reciprocal,
-                          (float(view.tile_origin_y + size - guard) - 1.5f) * reciprocal};
-}
-std::vector<std::uint32_t> visible_casters(const Mat4& view_projection,
-                                           std::span<const ShadowCasterBounds> casters) {
-    std::vector<std::uint32_t> result;
-    for (const auto& caster : casters)
-        if (intersects_frustum(caster.world, view_projection))
-            result.push_back(caster.draw_index);
-    std::sort(result.begin(), result.end());
-    result.erase(std::unique(result.begin(), result.end()), result.end());
-    return result;
-}
-bool supported_atlas(std::uint32_t size, bool available) {
-    return available && (size == 2048 || size == 1024);
-}
-void validate_local(const LocalLight& light) {
-    const auto invalid = [&](const char* field) {
-        throw std::invalid_argument("Local light " + light.stable_id + " has invalid " + field);
-    };
-    if (light.stable_id.empty())
-        invalid("stable_id");
-    if (!std::all_of(light.position.begin(), light.position.end(),
-                     [](float v) { return std::isfinite(v); }))
-        invalid("position");
-    if (!std::all_of(light.color.begin(), light.color.end(),
-                     [](float v) { return std::isfinite(v) && v >= 0; }))
-        invalid("color");
-    if (!std::isfinite(light.intensity) || light.intensity < 0)
-        invalid("intensity");
-    if (!std::isfinite(light.range) || light.range <= 0)
-        invalid("range");
-    if (light.kind == LocalLight::Kind::Spot) {
-        if (!std::isfinite(light.inner_angle) || !std::isfinite(light.outer_angle) ||
-            light.inner_angle < 0 || light.inner_angle > light.outer_angle ||
-            light.outer_angle >= std::numbers::pi_v<float> / 2 || light.outer_angle <= 0)
-            invalid("inner_angle/outer_angle");
-        if (!std::all_of(light.direction.begin(), light.direction.end(),
-                         [](float v) { return std::isfinite(v); }) ||
-            length(light.direction) < 1e-6f)
-            invalid("direction");
-    }
-}
-float projected_influence(const LocalLight& light, const Snapshot& frame) {
-    const auto distance = length(subtract(light.position, frame.eye));
-    const auto projection_scale =
-        std::max(std::abs(frame.projection[0]), std::abs(frame.projection[5]));
-    return light.range * projection_scale / std::max(distance, .1f);
-}
-ShadowView sun_view(const Snapshot& frame, const SunLight& sun,
-                    std::span<const ShadowCasterBounds> casters, float split_near,
-                    float split_far, std::uint32_t index, std::uint32_t atlas_size) {
-    ShadowView result;
-    result.kind = ShadowView::Kind::Sun;
-    result.light_id = sun.stable_id;
-    result.face_index = index;
-    result.split_near = split_near;
-    result.split_far = split_far;
-    tile(result, atlas_size, 2, index);
-    const auto direction = unit(sun.direction);
-    const auto up = std::abs(direction[1]) > .98f ? Vec3{0, 0, 1} : Vec3{0, 1, 0};
-    const auto light_origin_view = look_at({0, 0, 0}, direction, up);
-    if (!frame.camera_frustum) {
-        const auto light_eye = scale(direction, -30);
-        result.view_projection = multiply(orthographic(-20, 20, -20, 20, .1f, 80),
-                                          look_at(light_eye, {0, 0, 0}, up));
-        result.caster_indices = visible_casters(result.view_projection, casters);
-        return result;
-    }
-    const auto receivers = frustum_slice(*frame.camera_frustum, split_near, split_far);
-    Vec3 center{};
-    for (const auto corner : receivers)
-        center = add(center, scale(corner, 1.f / 8));
-    float radius{};
-    for (const auto corner : receivers)
-        radius = std::max(radius, length(subtract(corner, center)));
-    radius = std::max(.25f, std::ceil(radius * 16.f) / 16.f);
-    const auto center_light = project(light_origin_view, center);
-    const auto texel = (2 * radius) / float(result.usable_size);
-    result.snapped_center_x = std::round(center_light[0] / texel) * texel;
-    result.snapped_center_y = std::round(center_light[1] / texel) * texel;
-    const float left = result.snapped_center_x - radius;
-    const float right = result.snapped_center_x + radius;
-    const float bottom = result.snapped_center_y - radius;
-    const float top = result.snapped_center_y + radius;
-    float nearest_ray = std::numeric_limits<float>::infinity();
-    float furthest_ray = -nearest_ray;
-    for (const auto corner : receivers) {
-        const auto ray = dot(corner, direction);
-        nearest_ray = std::min(nearest_ray, ray);
-        furthest_ray = std::max(furthest_ray, ray);
-    }
-    for (const auto& caster : casters) {
-        if (!overlaps_xy(caster.world, light_origin_view, left, right, bottom, top))
-            continue;
-        result.caster_indices.push_back(caster.draw_index);
-        for (const auto corner : corners(caster.world)) {
-            const auto ray = dot(corner, direction);
-            nearest_ray = std::min(nearest_ray, ray);
-            furthest_ray = std::max(furthest_ray, ray);
-        }
-    }
-    std::sort(result.caster_indices.begin(), result.caster_indices.end());
-    result.caster_indices.erase(
-        std::unique(result.caster_indices.begin(), result.caster_indices.end()),
-        result.caster_indices.end());
-    const auto light_eye = scale(direction, nearest_ray - 1.f);
-    const auto view = look_at(light_eye, add(light_eye, direction), up);
-    const auto depth = std::max(2.f, furthest_ray - nearest_ray + 2.f);
-    result.view_projection = multiply(orthographic(left, right, bottom, top, .1f, depth),
-                                      view);
-    return result;
-}
-ShadowView local_view(const LocalLight& light, std::uint32_t face,
-                      std::span<const ShadowCasterBounds> casters) {
-    ShadowView result;
-    result.kind = light.kind == LocalLight::Kind::Point ? ShadowView::Kind::Point
-                                                        : ShadowView::Kind::Spot;
-    result.light_id = light.stable_id;
-    result.face_index = face;
-    static constexpr std::array<Vec3, 6> axes{{{1, 0, 0}, {-1, 0, 0}, {0, 1, 0},
-                                                {0, -1, 0}, {0, 0, 1}, {0, 0, -1}}};
-    static constexpr std::array<Vec3, 6> ups{{{0, -1, 0}, {0, -1, 0}, {0, 0, 1},
-                                               {0, 0, -1}, {0, -1, 0}, {0, -1, 0}}};
-    const auto direction = light.kind == LocalLight::Kind::Point ? axes.at(face)
-                                                                 : unit(light.direction);
-    const auto up = light.kind == LocalLight::Kind::Point ? ups.at(face)
-                    : std::abs(direction[1]) > .98f ? Vec3{0, 0, 1} : Vec3{0, 1, 0};
-    const auto near_plane = std::max(.0001f, std::min(.05f, light.range * .1f));
-    const auto fov = light.kind == LocalLight::Kind::Point
-        ? std::numbers::pi_v<float> / 2 : light.outer_angle * 2;
-    result.view_projection = multiply(
-        perspective(fov, 1, near_plane, light.range),
-        look_at(light.position, add(light.position, direction), up));
-    result.caster_indices = visible_casters(result.view_projection, casters);
-    return result;
-}
-} // namespace
-
-ShadowPlan build_shadow_plan(const Snapshot& frame,
-                             std::span<const ShadowCasterBounds> casters,
-                             const ShadowBudget& budget) {
-    for (const auto& caster : casters)
-        for (int axis = 0; axis < 3; ++axis)
-            if (!std::isfinite(caster.world.min[axis]) ||
-                !std::isfinite(caster.world.max[axis]) ||
-                caster.world.min[axis] > caster.world.max[axis])
-                throw std::invalid_argument("Shadow caster world bounds must be finite and ordered");
-    ShadowPlan plan;
-    plan.sun_atlas_size = supported_atlas(budget.sun_atlas_size, budget.sun_atlas_available)
-        ? budget.sun_atlas_size : 0;
-    plan.local_atlas_size = supported_atlas(budget.local_atlas_size, budget.local_atlas_available)
-        ? budget.local_atlas_size : 0;
-    std::unordered_set<std::string> ids;
-    std::vector<std::pair<std::size_t, float>> ranked;
-    ranked.reserve(frame.local_lights.size());
-    for (std::size_t i = 0; i < frame.local_lights.size(); ++i) {
-        const auto& light = frame.local_lights[i];
-        validate_local(light); // Validate overflow records too, before truncation.
-        if (!ids.insert(light.stable_id).second)
-            throw std::invalid_argument("Duplicate local light stable_id: " + light.stable_id);
-        ranked.emplace_back(i, projected_influence(light, frame));
-    }
-    std::sort(ranked.begin(), ranked.end(), [&](const auto& a, const auto& b) {
-        const auto& left = frame.local_lights[a.first];
-        const auto& right = frame.local_lights[b.first];
-        if (left.shadow_priority != right.shadow_priority)
-            return left.shadow_priority > right.shadow_priority;
-        if (a.second != b.second)
-            return a.second > b.second;
-        return left.stable_id < right.stable_id;
-    });
-    const auto selected = std::min<std::size_t>(ranked.size(),
-                                                std::min(budget.max_local_lights, 128u));
-    plan.omitted_local_lights = static_cast<std::uint32_t>(ranked.size() - selected);
-    for (std::size_t i = 0; i < selected; ++i)
-        plan.submitted_local_indices.push_back(ranked[i].first);
-
-    std::optional<SunLight> sun = frame.sun;
-    if (!sun && !frame.authored_lights_present && frame.local_lights.empty())
-        sun = SunLight{"legacy-sun", frame.light_direction, {1, 1, 1, 1}, 1, true};
-    if (sun && sun->casts_shadow) {
-        plan.requested_sun_cascades = frame.camera_frustum
-            ? std::min(4u, budget.max_sun_views) : 1u;
-        if (frame.camera_frustum &&
-            (frame.camera_frustum->near_plane <= 0 ||
-             frame.camera_frustum->far_plane <= frame.camera_frustum->near_plane ||
-             frame.camera_frustum->projection[0] == 0 ||
-             frame.camera_frustum->projection[5] == 0))
-            throw std::invalid_argument("Shadow camera frustum is invalid");
-        const float near_plane = frame.camera_frustum ? frame.camera_frustum->near_plane : .1f;
-        const float far_plane = frame.camera_frustum
-            ? std::min(frame.camera_frustum->far_plane, budget.max_shadow_distance) : 80.f;
-        if (far_plane <= near_plane)
-            throw std::invalid_argument("Shadow distance does not reach the camera near plane");
-        float previous = near_plane;
-        for (std::uint32_t i = 0; i < plan.requested_sun_cascades; ++i) {
-            const auto ratio = float(i + 1) / float(plan.requested_sun_cascades);
-            const auto logarithmic = near_plane * std::pow(far_plane / near_plane, ratio);
-            const auto uniform = near_plane + (far_plane - near_plane) * ratio;
-            const auto split = i + 1 == plan.requested_sun_cascades
-                ? far_plane : .5f * (logarithmic + uniform);
-            ShadowView view;
-            if (plan.sun_atlas_size)
-                view = sun_view(frame, *sun, casters, previous, split, i, plan.sun_atlas_size);
-            else {
-                view.kind = ShadowView::Kind::Sun;
-                view.light_id = sun->stable_id;
-                view.face_index = i;
-                view.split_near = previous;
-                view.split_far = split;
-                view.reason = ShadowDropReason::Unavailable;
-            }
-            if (plan.sun_atlas_size &&
-                view.caster_indices.size() <=
-                    budget.max_caster_draws - std::min(plan.caster_draws, budget.max_caster_draws)) {
-                view.valid = true;
-                plan.caster_draws += static_cast<std::uint32_t>(view.caster_indices.size());
-                ++plan.effective_sun_cascades;
-            } else {
-                if (plan.sun_atlas_size)
-                    view.reason = ShadowDropReason::CasterBudget;
-                view.caster_indices.clear();
-                ++plan.dropped_sun_views;
-            }
-            plan.sun_views.push_back(std::move(view));
-            previous = split;
-        }
-    }
-    for (const auto source : plan.submitted_local_indices) {
-        const auto& light = frame.local_lights[source];
-        LocalShadowAssignment assignment;
-        assignment.source_index = source;
-        assignment.first_view = static_cast<std::uint32_t>(plan.local_views.size());
-        const auto faces = light.kind == LocalLight::Kind::Point ? 6u : 1u;
-        if (!light.casts_shadow || light.intensity == 0) {
-            plan.local_assignments.push_back(assignment);
-            continue;
-        }
-        plan.local_faces_requested += faces;
-        if (!plan.local_atlas_size)
-            assignment.reason = ShadowDropReason::Unavailable;
-        else if (const auto capacity = std::min(budget.max_local_faces, 16u);
-                 faces > capacity - std::min(plan.local_faces_used, capacity))
-            assignment.reason = ShadowDropReason::TileBudget;
-        else {
-            std::vector<ShadowView> group;
-            std::uint32_t group_draws{};
-            for (std::uint32_t face = 0; face < faces; ++face) {
-                auto view = local_view(light, face, casters);
-                tile(view, plan.local_atlas_size, 4,
-                     plan.local_faces_used + face);
-                group_draws += static_cast<std::uint32_t>(view.caster_indices.size());
-                group.push_back(std::move(view));
-            }
-            if (group_draws > budget.max_caster_draws -
-                                  std::min(plan.caster_draws, budget.max_caster_draws))
-                assignment.reason = ShadowDropReason::CasterBudget;
-            else {
-                assignment.valid = true;
-                assignment.face_count = faces;
-                plan.local_faces_used += faces;
-                plan.caster_draws += group_draws;
-                for (auto& view : group) {
-                    view.valid = true;
-                    plan.local_views.push_back(std::move(view));
-                }
-            }
-        }
-        if (!assignment.valid) {
-            plan.dropped_local_faces += faces;
-            if (light.kind == LocalLight::Kind::Point)
-                plan.dropped_point_faces += 6;
-        }
-        plan.local_assignments.push_back(assignment);
-    }
-    return plan;
-}
-} // namespace faset::render

src/render/renderer.cpp

@@ -6,17 +6,14 @@
 #include <bit>
 #include <chrono>
 #include <cmath>
-#include <cstddef>
 #include <cstring>
 #include <faset/core/io.hpp>
 #include <faset/render/render_graph.hpp>
-#include <faset/render/lighting.hpp>
 #include <faset/render/renderer.hpp>
 #include <faset/render/visibility.hpp>
 #include <fstream>
 #include <iostream>
 #include <limits>
-#include <numbers>
 #include <optional>
 #include <stdexcept>
 #include <unordered_map>
@@ -75,40 +72,6 @@ struct ScenePush {
     std::array<std::uint32_t, 4> draw_info;
 };
 static_assert(sizeof(ScenePush) == 112);
-struct LightingHeaderGpu {
-    std::array<std::uint32_t, 4> counts{};
-    std::array<float, 4> sun_direction_intensity{};
-    std::array<float, 4> sun_color{};
-    std::array<float, 4> camera_forward_shadow_distance{};
-    std::array<float, 4> cascade_splits{};
-};
-struct LocalLightGpu {
-    std::array<float, 4> position_range{};
-    std::array<float, 4> direction_cos_outer{};
-    std::array<float, 4> color_intensity{};
-    std::array<float, 4> cone_type_shadow_view{};
-    std::array<float, 4> reserved{};
-};
-struct ShadowViewGpu {
-    Mat4 view_projection{identity};
-    std::array<float, 4> tile_scale_offset{};
-    std::array<float, 4> guarded_clamp{};
-    std::array<float, 4> bias_flags{};
-};
-static_assert(sizeof(LightingHeaderGpu) == 80 &&
-              offsetof(LightingHeaderGpu, sun_direction_intensity) == 16 &&
-              offsetof(LightingHeaderGpu, sun_color) == 32 &&
-              offsetof(LightingHeaderGpu, camera_forward_shadow_distance) == 48 &&
-              offsetof(LightingHeaderGpu, cascade_splits) == 64);
-static_assert(sizeof(LocalLightGpu) == 80 &&
-              offsetof(LocalLightGpu, direction_cos_outer) == 16 &&
-              offsetof(LocalLightGpu, color_intensity) == 32 &&
-              offsetof(LocalLightGpu, cone_type_shadow_view) == 48 &&
-              offsetof(LocalLightGpu, reserved) == 64);
-static_assert(sizeof(ShadowViewGpu) == 112 &&
-              offsetof(ShadowViewGpu, tile_scale_offset) == 64 &&
-              offsetof(ShadowViewGpu, guarded_clamp) == 80 &&
-              offsetof(ShadowViewGpu, bias_flags) == 96);
 std::array<float, 4> point(const Mat4& m, std::array<float, 4> p) {
     std::array<float, 4> o{};
     for (int r = 0; r < 4; ++r)
@@ -233,7 +196,6 @@ struct Renderer::Impl {
     std::vector<VkImageLayout> swap_layouts;
     Image color, depth, shadow;
     Buffer vertices, readback;
-    Buffer lighting_header, lighting_locals, lighting_views;
     SceneResources scene;
     InstanceTracker instance_tracker;
     std::unordered_map<std::string, std::size_t> previous_lods;
@@ -250,9 +212,6 @@ struct Renderer::Impl {
     std::unordered_map<const Texture*, CachedOpacity> opacity_cache;
     VkDescriptorSetLayout descriptor_layout{};
     VkDescriptorPool descriptor_pool{};
-    VkDescriptorSetLayout lighting_layout{};
-    VkDescriptorPool lighting_pool{};
-    VkDescriptorSet lighting_set{};
     VkSampler shadow_sampler{}, color_sampler{};
     VkPipelineLayout pipeline_layout{};
     VkPipeline pipeline{}, ui_pipeline{}, shadow_pipeline{}, sprite_pipeline{};
@@ -357,9 +316,6 @@ struct Renderer::Impl {
         destroy(scene.hzb[1]);
         destroy(vertices);
         destroy(readback);
-        destroy(lighting_header);
-        destroy(lighting_locals);
-        destroy(lighting_views);
         destroy(color);
         destroy(depth);
         destroy(shadow);
@@ -377,12 +333,8 @@ struct Renderer::Impl {
                 vkDestroyPipelineLayout(device, pipeline_layout, nullptr);
             if (descriptor_pool)
                 vkDestroyDescriptorPool(device, descriptor_pool, nullptr);
-            if (lighting_pool)
-                vkDestroyDescriptorPool(device, lighting_pool, nullptr);
             if (descriptor_layout)
                 vkDestroyDescriptorSetLayout(device, descriptor_layout, nullptr);
-            if (lighting_layout)
-                vkDestroyDescriptorSetLayout(device, lighting_layout, nullptr);
             if (shadow_sampler)
                 vkDestroySampler(device, shadow_sampler, nullptr);
             if (color_sampler)
@@ -937,31 +889,6 @@ struct Renderer::Impl {
         pi.pPoolSizes = sizes;
         check(vkCreateDescriptorPool(device, &pi, nullptr, &descriptor_pool),
               "Create descriptor pool");
-        std::array<VkDescriptorSetLayoutBinding, 4> lighting_bindings{};
-        for (std::uint32_t i = 0; i < lighting_bindings.size(); ++i)
-            lighting_bindings[i] = {i,
-                                    i == 3 ? VK_DESCRIPTOR_TYPE_SAMPLED_IMAGE
-                                           : VK_DESCRIPTOR_TYPE_STORAGE_BUFFER,
-                                    1, VK_SHADER_STAGE_FRAGMENT_BIT, nullptr};
-        li.bindingCount = static_cast<std::uint32_t>(lighting_bindings.size());
-        li.pBindings = lighting_bindings.data();
-        check(vkCreateDescriptorSetLayout(device, &li, nullptr, &lighting_layout),
-              "Create lighting descriptor layout");
-        VkDescriptorPoolSize lighting_sizes[] = {
-            {VK_DESCRIPTOR_TYPE_STORAGE_BUFFER, 3}, {VK_DESCRIPTOR_TYPE_SAMPLED_IMAGE, 1}};
-        pi.flags = 0;
-        pi.maxSets = 1;
-        pi.poolSizeCount = 2;
-        pi.pPoolSizes = lighting_sizes;
-        check(vkCreateDescriptorPool(device, &pi, nullptr, &lighting_pool),
-              "Create lighting descriptor pool");
-        VkDescriptorSetAllocateInfo lighting_allocation{};
-        lighting_allocation.sType = VK_STRUCTURE_TYPE_DESCRIPTOR_SET_ALLOCATE_INFO;
-        lighting_allocation.descriptorPool = lighting_pool;
-        lighting_allocation.descriptorSetCount = 1;
-        lighting_allocation.pSetLayouts = &lighting_layout;
-        check(vkAllocateDescriptorSets(device, &lighting_allocation, &lighting_set),
-              "Allocate lighting descriptors");
         VkSamplerCreateInfo si{};
         si.sType = VK_STRUCTURE_TYPE_SAMPLER_CREATE_INFO;
         si.magFilter = si.minFilter = VK_FILTER_NEAREST;
@@ -1082,9 +1009,8 @@ struct Renderer::Impl {
                                  sizeof(Push)};
         VkPipelineLayoutCreateInfo li{};
         li.sType = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO;
-        const std::array<VkDescriptorSetLayout, 2> set_layouts{descriptor_layout, lighting_layout};
-        li.setLayoutCount = static_cast<std::uint32_t>(set_layouts.size());
-        li.pSetLayouts = set_layouts.data();
+        li.setLayoutCount = 1;
+        li.pSetLayouts = &descriptor_layout;
         li.pushConstantRangeCount = 1;
         li.pPushConstantRanges = &push;
         check(vkCreatePipelineLayout(device, &li, nullptr, &pipeline_layout),
@@ -1294,14 +1220,14 @@ struct Renderer::Impl {
         layout.pBindings = hzb.data();
         check(vkCreateDescriptorSetLayout(device, &layout, nullptr, &scene.hzb_layout),
               "Create HZB descriptor layout");
-        const std::array<VkDescriptorSetLayout, 3> scene_layouts{
-            descriptor_layout, lighting_layout, scene.graphics_layout};
+        const std::array<VkDescriptorSetLayout, 2> scene_layouts{descriptor_layout,
+                                                                  scene.graphics_layout};
         VkPushConstantRange graphics_push{VK_SHADER_STAGE_VERTEX_BIT |
                                               VK_SHADER_STAGE_FRAGMENT_BIT,
                                           0, sizeof(ScenePush)};
         VkPipelineLayoutCreateInfo pipeline_info{};
         pipeline_info.sType = VK_STRUCTURE_TYPE_PIPELINE_LAYOUT_CREATE_INFO;
-        pipeline_info.setLayoutCount = static_cast<std::uint32_t>(scene_layouts.size());
+        pipeline_info.setLayoutCount = 2;
         pipeline_info.pSetLayouts = scene_layouts.data();
         pipeline_info.pushConstantRangeCount = 1;
         pipeline_info.pPushConstantRanges = &graphics_push;
@@ -1607,29 +1533,6 @@ struct Renderer::Impl {
                              VkBufferUsageFlags usage = 0) {
         upload_scene_buffer(buffer, values.data(), values.size() * sizeof(T), usage);
     }
-    void update_lighting_descriptors() {
-        const std::array<VkDescriptorBufferInfo, 3> buffers{{
-            {lighting_header.handle, 0, lighting_header.size},
-            {lighting_locals.handle, 0, lighting_locals.size},
-            {lighting_views.handle, 0, lighting_views.size}}};
-        const VkDescriptorImageInfo atlas{VK_NULL_HANDLE, shadow.view,
-                                          VK_IMAGE_LAYOUT_DEPTH_READ_ONLY_OPTIMAL};
-        std::array<VkWriteDescriptorSet, 4> writes{};
-        for (std::uint32_t i = 0; i < writes.size(); ++i) {
-            writes[i].sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET;
-            writes[i].dstSet = lighting_set;
-            writes[i].dstBinding = i;
-            writes[i].descriptorCount = 1;
-            writes[i].descriptorType = i == 3 ? VK_DESCRIPTOR_TYPE_SAMPLED_IMAGE
-                                               : VK_DESCRIPTOR_TYPE_STORAGE_BUFFER;
-            if (i == 3)
-                writes[i].pImageInfo = &atlas;
-            else
-                writes[i].pBufferInfo = &buffers[i];
-        }
-        vkUpdateDescriptorSets(device, static_cast<std::uint32_t>(writes.size()),
-                               writes.data(), 0, nullptr);
-    }
     void update_scene_descriptors(bool occlusion) {
         auto write_buffers = [&](VkDescriptorSet set, std::span<const Buffer* const> buffers,
                                  std::uint32_t first_binding) {
@@ -1722,7 +1625,6 @@ struct Renderer::Impl {
     void render(const Snapshot& snapshot) {
         auto start = std::chrono::steady_clock::now();
         statistics.draw_calls = statistics.culled_meshes = statistics.gpu_label_count = 0;
-        statistics.submitted_local_lights = statistics.omitted_local_lights = 0;
         statistics.gpu_bins = statistics.gpu_visible_instances =
             statistics.gpu_frustum_rejected = statistics.gpu_occlusion_deferred =
                 statistics.gpu_post_visible = 0;
@@ -1813,8 +1715,6 @@ struct Renderer::Impl {
         };
         std::vector<SelectedDraw> selected_draws;
         selected_draws.reserve(snapshot.draws.size());
-        std::vector<ShadowCasterBounds> shadow_casters;
-        shadow_casters.reserve(snapshot.draws.size());
         struct BuildingBin {
             const Mesh* mesh{};
             const Texture* texture{};
@@ -1824,17 +1724,10 @@ struct Renderer::Impl {
         std::vector<BuildingBin> building_bins;
         std::unordered_map<const Mesh*, std::pair<std::uint32_t, std::uint32_t>> mesh_ranges;
         std::unordered_map<std::string, std::size_t> current_lods;
-        for (std::size_t source_index = 0; source_index < snapshot.draws.size(); ++source_index) {
-            const auto& item = snapshot.draws[source_index];
+        for (const auto& item : snapshot.draws) {
             if (!item.mesh || item.mesh->vertices.empty())
                 continue;
             const auto source_bounds = world_bounds(item.mesh, item.model);
-            if (item.cast_shadow) {
-                if (source_index > UINT32_MAX)
-                    throw std::overflow_error("Shadow source draw index exceeds 32-bit capacity");
-                shadow_casters.push_back(
-                    {source_bounds, static_cast<std::uint32_t>(source_index)});
-            }
             std::vector<float> thresholds;
             std::vector<std::uint8_t> available;
             std::shared_ptr<const Mesh> selected_mesh = item.mesh;
@@ -2124,73 +2017,15 @@ struct Renderer::Impl {
                                     VK_BUFFER_USAGE_TRANSFER_DST_BIT);
             update_scene_descriptors(occlusion);
         }
-        std::optional<SunLight> sun = snapshot.sun;
-        if (!sun && !snapshot.authored_lights_present && snapshot.local_lights.empty())
-            sun = SunLight{"legacy-sun", snapshot.light_direction, {1, 1, 1, 1}, 1, true};
-        Vec3 direction = sun ? sun->direction : snapshot.light_direction;
+        Vec3 direction = snapshot.light_direction;
         float length = std::sqrt(direction[0] * direction[0] + direction[1] * direction[1] +
                                  direction[2] * direction[2]);
-        if (!std::isfinite(length) || length < 1e-5f) {
-            if (sun && sun->stable_id != "legacy-sun")
-                throw std::invalid_argument("Authored sun direction must be finite and nonzero");
+        if (length < 1e-5f) {
             direction = {-.5f, -1, -.3f};
             length = std::sqrt(1.34f);
         }
         for (auto& v : direction)
             v /= length;
-        LightingHeaderGpu lighting{};
-        lighting.counts[1] = sun ? 1u : 0u;
-        lighting.counts[2] = sun && sun->casts_shadow ? 1u : 0u;
-        lighting.sun_direction_intensity = {direction[0], direction[1], direction[2],
-                                            sun ? sun->intensity : 0};
-        lighting.sun_color = sun ? sun->color : Color{0, 0, 0, 1};
-        if (sun && (!std::isfinite(sun->intensity) || sun->intensity < 0 ||
-                    std::any_of(sun->color.begin(), sun->color.end(),
-                                [](float v) { return !std::isfinite(v) || v < 0; })))
-            throw std::invalid_argument("Authored sun radiance must be finite and nonnegative");
-        lighting.camera_forward_shadow_distance = {0, 0, -1, 80};
-        if (snapshot.camera_frustum) {
-            const auto& view = snapshot.camera_frustum->view;
-            lighting.camera_forward_shadow_distance = {-view[2], -view[6], -view[10], 80};
-        }
-        const auto shadow_plan = build_shadow_plan(snapshot, shadow_casters);
-        statistics.omitted_local_lights = shadow_plan.omitted_local_lights;
-        std::vector<LocalLightGpu> gpu_lights;
-        gpu_lights.reserve(shadow_plan.submitted_local_indices.size());
-        for (const auto source : shadow_plan.submitted_local_indices) {
-            const auto& local = snapshot.local_lights[source];
-            auto spot_direction = local.direction;
-            float spot_length = std::hypot(spot_direction[0], spot_direction[1],
-                                           spot_direction[2]);
-            if (!std::isfinite(spot_length) || spot_length < 1e-6f) {
-                if (local.kind == LocalLight::Kind::Spot)
-                    throw std::invalid_argument("Spotlight direction must be finite and nonzero");
-                spot_direction = {0, 0, -1};
-                spot_length = 1;
-            }
-            for (auto& axis : spot_direction)
-                axis /= spot_length;
-            LocalLightGpu gpu{};
-            gpu.position_range = {local.position[0], local.position[1], local.position[2],
-                                  local.range};
-            const bool spot = local.kind == LocalLight::Kind::Spot;
-            gpu.direction_cos_outer = {spot_direction[0], spot_direction[1], spot_direction[2],
-                                       spot ? std::cos(local.outer_angle) : 0.f};
-            gpu.color_intensity = {local.color[0], local.color[1], local.color[2],
-                                   local.intensity};
-            gpu.cone_type_shadow_view = {spot ? std::cos(local.inner_angle) : 1.f,
-                                         spot ? 1.f : 0.f, -1, 0};
-            gpu_lights.push_back(gpu);
-        }
-        lighting.counts[0] = static_cast<std::uint32_t>(gpu_lights.size());
-        statistics.submitted_local_lights = lighting.counts[0];
-        if (gpu_lights.empty())
-            gpu_lights.push_back({}); // Descriptors always point at a full initialized record.
-        const ShadowViewGpu empty_shadow_view{};
-        upload_scene_buffer(lighting_header, &lighting, sizeof(lighting), 0);
-        upload_scene_vector(lighting_locals, gpu_lights);
-        upload_scene_buffer(lighting_views, &empty_shadow_view, sizeof(empty_shadow_view), 0);
-        update_lighting_descriptors();
         Vec3 light_eye{-direction[0] * 30, -direction[1] * 30, -direction[2] * 30};
         Vec3 light_up = std::abs(direction[1]) > .98f ? Vec3{0, 0, 1} : Vec3{0, 1, 0};
         Push push{multiply(orthographic(-20, 20, -20, 20, .1f, 80),
@@ -2243,12 +2078,6 @@ struct Renderer::Impl {
             vkCmdSetViewport(command, 0, 1, &viewport);
             vkCmdSetScissor(command, 0, 1, &scissor);
         };
-        auto bind_material = [&](VkDescriptorSet material) {
-            const std::array<VkDescriptorSet, 2> sets{material, lighting_set};
-            vkCmdBindDescriptorSets(command, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline_layout,
-                                    0, static_cast<std::uint32_t>(sets.size()), sets.data(),
-                                    0, nullptr);
-        };
         auto draw_transparent = [&] {
             if (transparent_batches.empty())
                 return;
@@ -2259,7 +2088,8 @@ struct Renderer::Impl {
                                0, sizeof(push), &push);
             for (auto batch : transparent_batches) {
                 auto descriptor = textures.at(batch.texture).descriptor;
-                bind_material(descriptor);
+                vkCmdBindDescriptorSets(command, VK_PIPELINE_BIND_POINT_GRAPHICS,
+                                        pipeline_layout, 0, 1, &descriptor, 0, nullptr);
                 vkCmdDraw(command, batch.count, 1, batch.first, 0);
                 ++statistics.draw_calls;
             }
@@ -2272,7 +2102,8 @@ struct Renderer::Impl {
                                sizeof(push), &push);
             for (auto batch : sprite_batches) {
                 auto descriptor = textures.at(batch.texture).descriptor;
-                bind_material(descriptor);
+                vkCmdBindDescriptorSets(command, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline_layout,
+                                        0, 1, &descriptor, 0, nullptr);
                 vkCmdDraw(command, batch.count, 1, batch.first, 0);
                 ++statistics.draw_calls;
             }
@@ -2294,7 +2125,8 @@ struct Renderer::Impl {
                     continue;
                 vkCmdSetScissor(command, 0, 1, &scissor);
                 auto descriptor = textures.at(batch.texture).descriptor;
-                bind_material(descriptor);
+                vkCmdBindDescriptorSets(command, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline_layout,
+                                        0, 1, &descriptor, 0, nullptr);
                 vkCmdDraw(command, batch.count, 1, batch.first, 0);
                 ++statistics.draw_calls;
             }
@@ -2481,7 +2313,8 @@ struct Renderer::Impl {
             vkCmdPushConstants(command, pipeline_layout,
                                VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT, 0,
                                sizeof(push), &push);
-            bind_material(white_descriptor);
+            vkCmdBindDescriptorSets(command, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline_layout, 0, 1,
+                                    &white_descriptor, 0, nullptr);
             if (gpu_active && !gpu_frame.bins.empty()) {
                 VkDeviceSize scene_offset{};
                 vkCmdBindVertexBuffers(command, 0, 1, &scene.vertices.handle, &scene_offset);
@@ -2489,7 +2322,7 @@ struct Renderer::Impl {
                                   scene.graphics_pipeline);
                 for (std::uint32_t bin = 0; bin < gpu_frame.bins.size(); ++bin) {
                     auto descriptor = textures.at(gpu_frame.textures[bin]).descriptor;
-                    const std::array<VkDescriptorSet, 3> sets{descriptor, lighting_set,
+                    const std::array<VkDescriptorSet, 2> sets{descriptor,
                                                                scene.graphics_main};
                     vkCmdBindDescriptorSets(command, VK_PIPELINE_BIND_POINT_GRAPHICS,
                                             scene.graphics_pipeline_layout, 0, sets.size(),
@@ -2513,7 +2346,8 @@ struct Renderer::Impl {
             }
             for (auto batch : scene_batches) {
                 auto descriptor = textures.at(batch.texture).descriptor;
-                bind_material(descriptor);
+                vkCmdBindDescriptorSets(command, VK_PIPELINE_BIND_POINT_GRAPHICS, pipeline_layout,
+                                        0, 1, &descriptor, 0, nullptr);
                 vkCmdDraw(command, batch.count, 1, batch.first, 0);
                 ++statistics.draw_calls;
             }
@@ -2612,7 +2446,7 @@ struct Renderer::Impl {
                                       scene.graphics_pipeline);
                     for (std::uint32_t bin = 0; bin < gpu_frame.bins.size(); ++bin) {
                         auto descriptor = textures.at(gpu_frame.textures[bin]).descriptor;
-                        const std::array<VkDescriptorSet, 3> sets{descriptor, lighting_set,
+                        const std::array<VkDescriptorSet, 2> sets{descriptor,
                                                                    scene.graphics_post};
                         vkCmdBindDescriptorSets(command, VK_PIPELINE_BIND_POINT_GRAPHICS,
                                                 scene.graphics_pipeline_layout, 0,
@@ -2784,10 +2618,7 @@ struct Renderer::Impl {
         ++statistics.frame;
         statistics.gpu_allocated_bytes = vertices.allocation_size + readback.allocation_size +
                                          color.allocation_size + depth.allocation_size +
-                                         shadow.allocation_size +
-                                         lighting_header.allocation_size +
-                                         lighting_locals.allocation_size +
-                                         lighting_views.allocation_size;
+                                         shadow.allocation_size;
         statistics.texture_count = static_cast<std::uint32_t>(textures.size());
         for (const auto& [_, texture] : textures)
             statistics.gpu_allocated_bytes += texture.image.allocation_size;

src/render/shader_contract.cpp

@@ -34,21 +34,13 @@ void validate_layout(const Json& layout, std::string_view entry) {
     const bool fragment = entry == "fragmentMain";
     require(layout.at("stage") == (fragment ? "fragment" : "vertex"), "shader stage changed");
     const auto& descriptors = layout.at("descriptors");
-    require(descriptors.is_array() && descriptors.size() == 8, "descriptor count changed");
+    require(descriptors.is_array() && descriptors.size() == 4, "descriptor count changed");
     for (std::size_t i = 0; i < descriptors.size(); ++i) {
         const auto& binding = descriptors[i];
-        const auto set = i < 4 ? 0 : 1;
-        const auto slot = i % 4;
-        require(binding.at("set") == set && binding.at("binding") == slot &&
-                    binding.at("count") == 1,
+        require(binding.at("set") == 0 && binding.at("binding") == i && binding.at("count") == 1,
                 "descriptor set, binding or array count changed");
-        const auto* expected_type = set == 0 ? (slot % 2 ? "sampler" : "sampled_image_2d")
-                                    : slot == 3 ? "sampled_image_2d" : "storage_buffer";
-        require(binding.at("type") == expected_type,
+        require(binding.at("type") == (i % 2 ? "sampler" : "sampled_image_2d"),
                 "descriptor type changed");
-        if (set == 1 && slot < 3)
-            require(binding.at("element_stride") == (slot == 2 ? 112 : 80),
-                    "lighting storage record stride changed");
         require(fragment || !binding.at("used").get<bool>(),
                 "vertex texture bindings are unsupported");
     }
@@ -106,7 +98,7 @@ void validate_gpu_layout(const Json& layout, std::string_view entry) {
     const std::array<int, 3> graphics_strides{224, 4, 208};
     for (std::size_t i = 0; i < expected_count; ++i) {
         const auto& binding = descriptors[i];
-        require(binding.at("set") == (graphics ? 2 : 0) && binding.at("binding") == i &&
+        require(binding.at("set") == (graphics ? 1 : 0) && binding.at("binding") == i &&
                     binding.at("count") == 1,
                 "GPU descriptor set, binding or count changed");
         const int stride = graphics ? graphics_strides[i] : hzb ? 0 : compute_strides[i];

tests/authoring_tests.cpp

@@ -2,7 +2,6 @@
 #include <faset/authoring/templates.hpp>
 #include <faset/authoring/transforms.hpp>
 #include <faset/core/io.hpp>
-#include <cstdint>
 #include <iostream>
 
 #define CHECK(x)                                                                                   \
@@ -26,32 +25,6 @@ int main() {
     const auto root = std::filesystem::temp_directory_path() / ("faset-authoring-" + new_id());
     try {
         auto schemas = builtin_schemas();
-        const auto light = schemas.schema("faset.light");
-        CHECK(light["version"] == 1);
-        const auto defaults = schemas.default_fields("faset.light");
-        CHECK(defaults["kind"] == "directional");
-        CHECK(defaults["enabled"] == true);
-        CHECK(defaults["range"] == 10.0);
-        CHECK(defaults["inner_angle"] < defaults["outer_angle"]);
-        CHECK(defaults["casts_shadow"] == true);
-        CHECK(defaults["shadow_priority"] == 0);
-        auto light_component = Json{{"type", "faset.light"}, {"version", 1}, {"fields", defaults}};
-        schemas.validate_component(light_component);
-        light_component["fields"]["kind"] = "area";
-        fails([&] { schemas.validate_component(light_component); }, "validation.enum");
-        light_component["fields"]["kind"] = "point";
-        light_component["fields"]["range"] = 0;
-        fails([&] { schemas.validate_component(light_component); }, "validation.minimum");
-        light_component["fields"]["range"] = 10;
-        light_component["fields"]["intensity"] = -1;
-        fails([&] { schemas.validate_component(light_component); }, "validation.minimum");
-        light_component["fields"] = {{"kind", "spot"}, {"inner_angle", 0.9}};
-        fails([&] { schemas.validate_component(light_component); }, "validation.light_cone");
-        light_component["fields"] = {{"kind", "spot"},
-                                      {"inner_angle", 0.2},
-                                      {"outer_angle", 0.5},
-                                      {"shadow_priority", std::int64_t{2147483648}}};
-        fails([&] { schemas.validate_component(light_component); }, "validation.maximum");
         AuthoringService service(root, schemas);
         auto created = service.create("Courtyard", 3);
         const std::string id = created["id"];

tests/build_cache_tests.cpp

@@ -0,0 +1,196 @@
+#include <faset/core/io.hpp>
+#include <faset/editor/build_cache.hpp>
+#include <faset/editor/build_service.hpp>
+#include <faset/scripting/project.hpp>
+#include <iostream>
+
+using namespace faset;
+namespace fs = std::filesystem;
+
+namespace {
+void check(bool condition, std::string_view message) {
+    if (!condition)
+        throw std::runtime_error(std::string(message));
+}
+void run(const fs::path& root) {
+    const auto project = root / "project";
+    const auto scripts = project / "Scripts";
+    atomic_write(scripts / "Gameplay.cpp", "#include \"Gameplay.hpp\"\n");
+    atomic_write(scripts / "Gameplay.hpp", "#pragma once\n");
+    atomic_write(scripts / "Extensions/Extra.hpp", "#define SPEED 1\n");
+    const auto compiler = root / "fake-compiler";
+    const auto cmake = root / "fake-cmake";
+    const auto slang = root / "fake-slangc";
+    atomic_write(compiler, "compiler-v1\n");
+    atomic_write(cmake, "cmake-v1\n");
+    atomic_write(slang, "slang-v1\n");
+    editor::BuildConfig config;
+    config.project_root = project;
+    config.engine_root = path_from_utf8(FASET_ENGINE_SOURCE);
+    config.build_directory = project / ".faset/build";
+    config.cmake = path_to_utf8(cmake);
+    config.configure_arguments = {
+        "-DCMAKE_C_COMPILER=" + path_to_utf8(compiler),
+        "-DCMAKE_CXX_COMPILER=" + path_to_utf8(compiler),
+        "-DSLANGC_EXECUTABLE=" + path_to_utf8(slang)};
+
+    const scripting::LuaProject none;
+    const auto initial = editor::capture_build_inputs(config, none);
+    atomic_write(scripts / "Extensions/Extra.hpp", "#define SPEED 2\n");
+    const auto changed_header = editor::capture_build_inputs(config, none);
+    check(initial.source_hash != changed_header.source_hash &&
+              initial.fingerprint() != changed_header.fingerprint(),
+          "Nested gameplay header changes the complete source snapshot");
+
+    atomic_write(scripts / "main.lua", "return {}\n");
+    atomic_write_json(project / "project.faset.json",
+                      {{"format", "faset.project"},
+                       {"version", 1},
+                       {"scripting", {{"lua", {{"scripts", {"Scripts/main.lua"}}}}}}});
+    auto lua = scripting::loadLuaProject(project);
+    const auto with_lua = editor::capture_build_inputs(config, lua);
+    atomic_write(scripts / "other.lua", "return {}\n");
+    auto manifest = read_json(project / "project.faset.json");
+    manifest["scripting"]["lua"]["scripts"].push_back("Scripts/other.lua");
+    atomic_write_json(project / "project.faset.json", manifest);
+    lua = scripting::loadLuaProject(project);
+    const auto changed_declaration = editor::capture_build_inputs(config, lua);
+    check(with_lua.source_hash != changed_declaration.source_hash,
+          "Lua entry declaration changes the source snapshot");
+
+    const auto native = config.build_directory / "Debug";
+    editor::ensure_native_toolchain_stamp(config, native, changed_declaration);
+    atomic_write(native / "sentinel", "keep\n");
+    editor::ensure_native_toolchain_stamp(config, native, changed_declaration);
+    check(fs::exists(native / "sentinel"), "Unchanged toolchain preserves the native tree");
+    atomic_write(compiler, "compiler-v2\n");
+    const auto changed_tool = editor::capture_build_inputs(config, lua);
+    check(changed_tool.source_hash == changed_declaration.source_hash &&
+              changed_tool.toolchain_hash != changed_declaration.toolchain_hash,
+          "Changing compiler bytes at the same path changes toolchain identity");
+    editor::ensure_native_toolchain_stamp(config, native, changed_tool);
+    check(!fs::exists(native / "sentinel"),
+          "Changed toolchain invalidates only the generated native tree");
+
+    const auto user_directory = root / "important-user-data";
+    atomic_write(user_directory / "do-not-delete.txt", "valuable\n");
+    bool refused_unowned{};
+    try {
+        editor::ensure_native_toolchain_stamp(config, user_directory, changed_tool);
+    } catch (const std::exception&) {
+        refused_unowned = true;
+    }
+    check(refused_unowned && fs::is_regular_file(user_directory / "do-not-delete.txt"),
+          "Unowned native directory is never cleared");
+    std::error_code native_link_error;
+    fs::create_directory_symlink(user_directory, config.build_directory / "Release",
+                                 native_link_error);
+    if (!native_link_error) {
+        bool refused_link{};
+        try {
+            editor::ensure_native_toolchain_stamp(config, config.build_directory / "Release",
+                                                  changed_tool);
+        } catch (const std::exception&) {
+            refused_link = true;
+        }
+        check(refused_link && fs::is_regular_file(user_directory / "do-not-delete.txt"),
+              "Symlinked native directory cannot redirect cleanup into user data");
+    }
+
+    const auto relative_tool = project / "tools/cmake-fixture";
+    atomic_write(relative_tool, "relative-cmake-v1\n");
+    auto relative_config = config;
+    relative_config.cmake = "tools/cmake-fixture";
+    const auto relative_before = editor::capture_build_inputs(relative_config, lua);
+    atomic_write(relative_tool, "relative-cmake-v2\n");
+    check(relative_before.toolchain_hash !=
+              editor::capture_build_inputs(relative_config, lua).toolchain_hash,
+          "Relative CMake executable resolves from the project working directory");
+    auto typed_config = config;
+    const auto typed_compiler = root / "typed-compiler";
+    atomic_write(typed_compiler, "typed-v1\n");
+    typed_config.configure_arguments = {
+        "-DCMAKE_C_COMPILER:FILEPATH=" + path_to_utf8(typed_compiler)};
+    const auto typed_before = editor::capture_build_inputs(typed_config, lua);
+    atomic_write(typed_compiler, "typed-v2\n");
+    check(typed_before.toolchain_hash !=
+              editor::capture_build_inputs(typed_config, lua).toolchain_hash,
+          "Typed CMake compiler overrides are included in toolchain identity");
+    auto malicious_config = config;
+    malicious_config.configure_arguments.push_back(
+        "-DFASET_GAMEPLAY_SOURCE_DIR:PATH=" + path_to_utf8(root / "outside"));
+    bool refused_source_override{};
+    try {
+        (void)editor::capture_build_inputs(malicious_config, lua);
+    } catch (const std::exception&) {
+        refused_source_override = true;
+    }
+    check(refused_source_override,
+          "Configure arguments cannot redirect gameplay compilation away from hashed Scripts");
+
+    const auto staged = editor::stage_gameplay_sources(config, changed_tool, lua,
+                                                        "snapshot-fixture");
+    check(staged != scripts && fs::is_regular_file(staged / "Gameplay.cpp") &&
+              read_text(staged / "Extensions/Extra.hpp") == "#define SPEED 2\n",
+          "Native gameplay compilation uses a complete staged Scripts snapshot");
+    atomic_write(scripts / "Extensions/Extra.hpp", "#define SPEED 999\n");
+    check(read_text(staged / "Extensions/Extra.hpp") == "#define SPEED 2\n",
+          "A live edit cannot alter the source bytes of an in-flight native build");
+    atomic_write(scripts / "Extensions/Extra.hpp", "#define SPEED 2\n");
+    check(editor::stage_gameplay_sources(config, changed_tool, lua, "snapshot-again") ==
+              staged,
+          "Identical sources retain a stable native path for incremental Ninja builds");
+
+    atomic_write(native / "faset_player", "player-v1\n");
+    atomic_write(native / "faset_schema_exporter", "exporter-v1\n");
+    atomic_write(native / "CMakeCache.txt", "recipe-v1\n");
+    atomic_write(native / "shaders/vertexMain.spv", "shader-v1\n");
+    atomic_write(native / "faset_runtime.dll", "runtime-v1\n");
+    auto package_key = [&] (const editor::BuildInputs& inputs) {
+        return editor::build_package_key(inputs, native, "Debug", native / "faset_player",
+                                         native / "faset_schema_exporter");
+    };
+    const auto first_key = package_key(changed_tool);
+    check(first_key != package_key(changed_declaration) &&
+              first_key != package_key(with_lua),
+          "Toolchain and Lua source changes invalidate package identity");
+    auto option_config = config;
+    option_config.configure_arguments.push_back("-DFASET_TEST_OPTION=ON");
+    check(first_key != package_key(editor::capture_build_inputs(option_config, lua)),
+          "Configure option changes invalidate package identity");
+    atomic_write(native / "shaders/vertexMain.spv", "shader-v2\n");
+    check(first_key != package_key(changed_tool),
+          "Shader bytes invalidate package identity");
+    atomic_write(native / "shaders/vertexMain.spv", "shader-v1\n");
+    atomic_write(native / "faset_runtime.dll", "runtime-v2\n");
+    check(first_key != package_key(changed_tool),
+          "Runtime DLL bytes invalidate package identity");
+
+    fs::create_directories(root / "outside");
+    std::error_code link_error;
+    fs::create_directory_symlink(root / "outside", scripts / "linked", link_error);
+    if (!link_error) {
+        bool rejected = false;
+        try {
+            (void)editor::capture_build_inputs(config, lua);
+        } catch (const std::exception&) {
+            rejected = true;
+        }
+        check(rejected, "Source snapshot refuses a symlink escaping Scripts");
+    }
+}
+} // namespace
+
+int main() {
+    const auto root = fs::temp_directory_path() / path_from_utf8("Faset build cache Café 世界 " + new_id());
+    try {
+        run(root);
+        fs::remove_all(root);
+        std::cout << "Source, toolchain and native package identity contracts passed\n";
+        return 0;
+    } catch (const std::exception& error) {
+        std::cerr << error.what() << '\n';
+        fs::remove_all(root);
+        return 1;
+    }
+}

tests/build_diagnostics_tests.cpp

@@ -0,0 +1,75 @@
+#include <faset/editor/build_diagnostics.hpp>
+#include <iostream>
+#include <stdexcept>
+
+using namespace faset;
+namespace fs = std::filesystem;
+
+namespace {
+void check(bool condition, std::string_view message) {
+    if (!condition)
+        throw std::runtime_error(std::string(message));
+}
+void contracts() {
+    const auto project = fs::path("/project");
+    auto rows = editor::parse_build_diagnostics(
+        "/project/Scripts/Game.cpp:17:4: error: bad field\n", "compile", project);
+    check(rows.size() == 1 && rows[0].at("file") == "Scripts/Game.cpp" &&
+              rows[0].at("line") == 17 && rows[0].at("column") == 4 &&
+              rows[0].at("severity") == "error" && rows[0].at("phase") == "compile",
+          "Clang error has a project-relative source location");
+    rows = editor::parse_build_diagnostics(
+        "\x1b[31mScripts/player.lua:6: unexpected symbol near '='\x1b[0m\n",
+        "schema", project);
+    check(rows.size() == 1 && rows[0].at("file") == "Scripts/player.lua" &&
+              rows[0].at("line") == 6 && rows[0].at("severity") == "error" &&
+              rows[0].at("message") == "unexpected symbol near '='",
+          "Lua syntax error and ANSI stripping work");
+    const auto windows = fs::path(R"(C:\Café)");
+    rows = editor::parse_build_diagnostics(
+        R"(C:\Café\Scripts\Game.cpp(17,4): error C2143: syntax error)" "\n"
+        R"(C:\Café\Scripts\Game.cpp:19:2: warning: suspicious conversion)" "\n",
+        "compile", windows);
+    check(rows.size() == 2 && rows[0].at("file") == "Scripts/Game.cpp" &&
+              rows[0].at("code") == "C2143" && rows[0].at("line") == 17 &&
+              rows[1].at("severity") == "warning" && rows[1].at("line") == 19,
+          "Windows drive colon and Unicode directory remain intact");
+    rows = editor::parse_build_diagnostics(
+        "Scripts/Game.cpp:9:3: error: missing value\n"
+        "    broken call\n"
+        "    ^~~~~~\n"
+        "Scripts/Game.cpp:4:1: note: declared here\n",
+        "compile", project);
+    check(rows.size() == 2 && rows[0].at("severity") == "error" &&
+              rows[1].at("severity") == "note" && rows[1].at("file") == "Scripts/Game.cpp",
+          "Caret and source excerpts do not become duplicate diagnostics");
+    rows = editor::parse_build_diagnostics(
+        "/outside/Scripts/Game.cpp:4:2: error: external\n"
+        "../Scripts/Escape.cpp:5:2: error: escaped\n",
+        "compile", project);
+    check(rows.size() == 2 && !rows[0].contains("file") && !rows[1].contains("file"),
+          "External and traversing sources are never navigable");
+    rows = editor::parse_build_diagnostics(
+        "Scripts/../Scripts/Game.cpp:4:2: error: disguised traversal\n"
+        "Scripts/Game.cpp:4:0: error: invalid column\n",
+        "compile", project);
+    check(rows.size() == 1 && !rows[0].contains("file"),
+          "Traversal stays non-navigable and zero columns are rejected");
+    std::string noisy;
+    for (int index = 0; index < 300; ++index)
+        noisy += "Scripts/Game.cpp:2:1: warning: repeated\n";
+    check(editor::parse_build_diagnostics(noisy, "compile", project).size() <= 200,
+          "Structured diagnostic count is bounded");
+}
+} // namespace
+
+int main() {
+    try {
+        contracts();
+        std::cout << "Build diagnostic parsing contracts passed\n";
+        return 0;
+    } catch (const std::exception& error) {
+        std::cerr << error.what() << '\n';
+        return 1;
+    }
+}

tests/build_schema_tests.cpp

@@ -142,11 +142,72 @@ int test_main(int argc, char** argv) {
         config.configure_arguments = {"-DCMAKE_CXX_COMPILER=fixture-does-not-compile"};
         editor::BuildService builds(config);
         builds.scaffold("Schema publication", 2);
+        atomic_write(config.project_root / "Scripts/Extensions/BuildOnly.hpp",
+                     "#define BUILD_ONLY 1\n");
         authoring::AuthoringService authoring(config.project_root, authoring::builtin_schemas());
         const auto valid = manifest();
         atomic_write_json(config.project_root / "schema-fixture.json", valid);
-        const auto first = builds.wait(builds.start_build());
+        {
+            auto compiler_config = config;
+            compiler_config.project_root = root / "c-only-compiler-project";
+            compiler_config.configure_arguments = {
+                "-DCMAKE_C_COMPILER:FILEPATH=fixture-c-only"};
+            editor::BuildService compiler_build(compiler_config);
+            compiler_build.scaffold("Compiler argument fixture", 2);
+            atomic_write_json(compiler_config.project_root / "schema-fixture.json", valid);
+            const auto compiler_result = compiler_build.wait(compiler_build.start_build());
+            check(compiler_result.state == "succeeded",
+                  "C-only compiler override fixture builds: " + compiler_result.error);
+            const auto compiler_args =
+                read_json(compiler_config.project_root / "configure-fixture.json");
+            std::size_t c_overrides{};
+            bool cxx_default{};
+            for (const auto& arg : compiler_args) {
+                const auto text = arg.get<std::string>();
+                if (text.starts_with("-DCMAKE_C_COMPILER")) {
+                    ++c_overrides;
+                    check(text == "-DCMAKE_C_COMPILER:FILEPATH=fixture-c-only",
+                          "Typed C override is not replaced by a default compiler");
+                }
+                if (text.starts_with("-DCMAKE_CXX_COMPILER="))
+                    cxx_default = true;
+            }
+            check(c_overrides == 1 && cxx_default,
+                  "C and C++ compiler defaults are selected independently");
+        }
+        auto first = builds.wait(builds.start_build());
         check(first.state == "succeeded", "Valid custom schema v2 publishes: " + first.error);
+        fs::path compiled_scripts;
+        for (const auto& arg : read_json(config.project_root / "configure-fixture.json")) {
+            const auto text = arg.get<std::string>();
+            constexpr std::string_view prefix = "-DFASET_GAMEPLAY_SOURCE_DIR=";
+            if (text.starts_with(prefix))
+                compiled_scripts = path_from_utf8(text.substr(prefix.size()));
+        }
+        check(!compiled_scripts.empty() &&
+                  compiled_scripts != config.project_root / "Scripts" &&
+                  read_text(compiled_scripts / "Extensions/BuildOnly.hpp") ==
+                      "#define BUILD_ONLY 1\n",
+              "Native C++ build receives the immutable source snapshot");
+        const auto repeated = builds.wait(builds.start_build());
+        check(repeated.state == "succeeded" &&
+                  repeated.result.at("generation") == first.result.at("generation") &&
+                  repeated.result.at("schema_cache_hit") == true &&
+                  repeated.result.at("generation_reused") == true &&
+                  read_text(config.project_root / "schema-export-count.txt") == "1",
+              "Unchanged native build reuses a verified schema generation");
+        atomic_write(path_from_utf8(first.result.at("schema").get<std::string>()), "truncated");
+        first = builds.wait(builds.start_build());
+        check(first.state == "succeeded" && first.result.at("schema_cache_hit") == false &&
+                  read_text(config.project_root / "schema-export-count.txt") == "2",
+              "Corrupt schema cannot be a cache hit");
+        atomic_write(path_from_utf8(first.result.at("directory").get<std::string>()) /
+                         "shaders/vertexMain.spv",
+                     "corrupt");
+        first = builds.wait(builds.start_build());
+        check(first.state == "succeeded" && first.result.at("schema_cache_hit") == false &&
+                  read_text(config.project_root / "schema-export-count.txt") == "3",
+              "Corrupt shader cannot be a cache hit");
         const auto directory = path_from_utf8(first.result.at("directory").get<std::string>());
         for (const auto* entry : {"gpuVertexMain", "gpuShadowMain", "gpuCullMain",
                                   "gpuHzbMain", "gpuPostCullMain"})
@@ -161,6 +222,34 @@ int test_main(int argc, char** argv) {
         const auto previous_player = sha256_file(player);
         const auto previous_schema = read_text(schema);
         const auto previous_manifest = read_text(directory / "manifest.json");
+        atomic_write(config.project_root / "emit-clang-error-and-fail-build", "fixture\n");
+        const auto compile_failed = builds.wait(builds.start_build());
+        check(compile_failed.state == "failed" &&
+                  read_text(last_build) == previous_pointer &&
+                  compile_failed.json().at("diagnostics").size() == 1 &&
+                  compile_failed.json().at("diagnostics")[0].at("file") ==
+                      "Scripts/Gameplay.cpp" &&
+                  compile_failed.log.find("fixture compile failure") != std::string::npos,
+              "Failed compiler output retains raw log and structured source location");
+        fs::remove(config.project_root / "emit-clang-error-and-fail-build");
+        atomic_write(config.project_root / "fail-unparseable-build", "fixture\n");
+        const auto generic_failed = builds.wait(builds.start_build());
+        check(generic_failed.state == "failed" &&
+                  generic_failed.json().at("diagnostics").size() == 1 &&
+                  generic_failed.json().at("diagnostics")[0].at("severity") == "error" &&
+                  !generic_failed.json().at("diagnostics")[0].contains("file") &&
+                  read_text(last_build) == previous_pointer,
+              "Unparseable process failure has a non-navigable diagnostic");
+        fs::remove(config.project_root / "fail-unparseable-build");
+        atomic_write(config.project_root / "Scripts/Extensions/BuildOnly.hpp",
+                     "#define BUILD_ONLY 3\n");
+        atomic_write(config.project_root / "mutate-cpp-header-during-build", "fixture\n");
+        const auto raced_header = builds.wait(builds.start_build());
+        check(raced_header.state == "failed" && read_text(last_build) == previous_pointer,
+              "Header changed during schema export cannot publish a mixed build");
+        fs::remove(config.project_root / "mutate-cpp-header-during-build");
+        atomic_write(config.project_root / "Scripts/Extensions/BuildOnly.hpp",
+                     "#define BUILD_ONLY 1\n");
         check(!first.result.at("lua_enabled").get<bool>() &&
                   !fs::exists(directory / "project.faset.json"),
               "C++-only build publishes no Lua sources or project manifest");
@@ -169,6 +258,11 @@ int test_main(int argc, char** argv) {
               "C++-only build explicitly disables the Lua VM in CMake");
         authoring.replace_external_schemas(read_json(schema));
         const auto previous_registry = authoring.schemas().manifest();
+        std::size_t published_generations{};
+        for (const auto& entry : fs::directory_iterator(directory.parent_path())) {
+            (void)entry;
+            ++published_generations;
+        }
         check(authoring.schemas().schema("game.mover").at("version") == 2,
               "Matching custom v2 metadata reaches authoring");
         migration_contracts(config.project_root / "migration-contracts", read_json(schema));
@@ -252,9 +346,11 @@ int test_main(int argc, char** argv) {
             std::size_t generations{};
             for (const auto& entry : fs::directory_iterator(directory.parent_path())) {
                 ++generations;
-                check(entry.path() == directory, "Invalid build leaves no staging or generation");
+                check(!entry.path().filename().string().starts_with(".staging-"),
+                      "Invalid build leaves no staging generation");
             }
-            check(generations == 1, "Only the validated build generation remains");
+            check(generations == published_generations,
+                  "Invalid build publishes no new generation");
             bool rejected{};
             try {
                 authoring.replace_external_schemas(invalid[index]);
@@ -305,6 +401,8 @@ int test_main(int argc, char** argv) {
               "Later edits never mutate an already published Lua generation");
         const auto lua_pointer = read_text(last_build);
         for (const auto* marker : {"mutate-lua-during-build", "mutate-lua-snapshot"}) {
+            atomic_write(config.project_root / "Scripts/main.lua",
+                         std::string(lua_source) + "-- force a schema export\n");
             atomic_write(config.project_root / marker, "fixture\n");
             const auto raced = builds.wait(builds.start_build());
             check(raced.state == "failed" && read_text(last_build) == lua_pointer,

tests/build_schema_tool.cpp

@@ -8,6 +8,9 @@ using namespace faset;
 int tool_main(int argc, char** argv) {
     try {
         if (argc >= 3 && std::string_view(argv[1]) == "--output") {
+            const auto count_file = fs::path("schema-export-count.txt");
+            const auto count = fs::exists(count_file) ? std::stoi(read_text(count_file)) : 0;
+            atomic_write(count_file, std::to_string(count + 1));
             if (argc == 5 && std::string_view(argv[3]) == "--project") {
                 const auto snapshot = path_from_utf8(argv[4]);
                 const auto project = read_json(snapshot / "project.faset.json");
@@ -21,6 +24,8 @@ int tool_main(int argc, char** argv) {
                 if (fs::exists("mutate-lua-snapshot"))
                     atomic_write(snapshot / "Scripts/main.lua", "-- corrupt snapshot\n");
             }
+            if (fs::exists("mutate-cpp-header-during-build"))
+                atomic_write("Scripts/Extensions/BuildOnly.hpp", "#define BUILD_ONLY 2\n");
             atomic_write_json(path_from_utf8(argv[2]), read_json("schema-fixture.json"));
             return 0;
         }
@@ -34,8 +39,18 @@ int tool_main(int argc, char** argv) {
             std::cout << "Native packaging fixture validated\n";
             return 0;
         }
-        if (argc > 2 && std::string_view(argv[1]) == "--build")
+        if (argc > 2 && std::string_view(argv[1]) == "--build") {
+            if (fs::exists("emit-clang-error-and-fail-build")) {
+                std::cerr << path_to_utf8(fs::current_path() / "Scripts/Gameplay.cpp")
+                          << ":7:3: error: fixture compile failure\n";
+                return 1;
+            }
+            if (fs::exists("fail-unparseable-build")) {
+                std::cerr << "Synthetic native build failed without a source location\n";
+                return 1;
+            }
             return 0;
+        }
         fs::path build;
         for (int i = 1; i + 1 < argc; ++i)
             if (std::string_view(argv[i]) == "-B")

tests/build_service_tests.cpp

@@ -1,8 +1,12 @@
 #include "assets_image_fixtures.hpp"
+#include <algorithm>
+#include <atomic>
 #include <bit>
 #include <chrono>
 #include <cstdlib>
+#include <functional>
 #include <faset/assets/asset_pipeline.hpp>
+#include <faset/authoring/service.hpp>
 #include <faset/core/hash.hpp>
 #include <faset/core/io.hpp>
 #include <faset/core/process.hpp>
@@ -42,6 +46,102 @@ Json scene(int dimension) {
             {"name", "Build test"},      {"dimension", dimension}, {"entities", Json::array()},
             {"instances", Json::array()}};
 }
+void starter_contracts(const fs::path& root) {
+    for (const int dimension : {2, 3}) {
+        for (const char* language : {"cpp", "lua"}) {
+            const auto project = root / path_from_utf8(std::string("Starter café ") + language +
+                                                        std::to_string(dimension));
+            editor::BuildConfig config;
+            config.project_root = project;
+            config.engine_root = path_from_utf8(FASET_ENGINE_SOURCE);
+            editor::BuildService service(config);
+            service.scaffold("Starter", dimension, language);
+            const auto manifest = read_json(project / "project.faset.json");
+            const auto start = read_json(project / "Scenes/main.scene.json");
+            require(manifest.at("dimension") == dimension &&
+                        manifest.at("start_scene") == "Scenes/main.scene.json",
+                    "Explicit starter has the requested scene type and startup path");
+            require(start.at("dimension") == dimension && !start.at("entities").empty(),
+                    "Starter scene is valid and has visible contents");
+            auto builtins = start;
+            bool has_behavior = false;
+            for (auto& entity : builtins["entities"]) {
+                auto& components = entity["components"].get_ref<Json::array_t&>();
+                std::erase_if(components, [&](const Json& component) {
+                    const auto custom =
+                        !component.at("type").get<std::string>().starts_with("faset.");
+                    has_behavior |= custom;
+                    return custom;
+                });
+            }
+            require(has_behavior, "Starter scene binds its gameplay behavior");
+            authoring::validate_scene(builtins, authoring::builtin_schemas());
+            if (std::string_view(language) == "lua") {
+                require(!fs::exists(project / "Scripts/Gameplay.cpp") &&
+                            !fs::exists(project / "Scripts/Gameplay.hpp"),
+                        "Lua starter has no C++ gameplay stub");
+                require(manifest.at("scripting").at("lua").at("scripts") ==
+                            Json::array({"Scripts/main.lua"}) &&
+                            scripting::loadLuaProject(project).enabled() &&
+                            fs::is_regular_file(project / ".luarc.json") &&
+                            fs::is_regular_file(project / "Scripts/.luarc.json") &&
+                            fs::is_regular_file(project / ".faset/lua/faset.lua"),
+                        "Lua starter declares an actual runnable module");
+            } else {
+                require(fs::is_regular_file(project / "Scripts/Gameplay.cpp") &&
+                            fs::is_regular_file(project / "Scripts/Gameplay.hpp") &&
+                            !manifest.contains("scripting"),
+                        "C++ starter contains its compiled gameplay module");
+            }
+            const auto marker = read_text(project / "Scenes/main.scene.json");
+            bool rejected = false;
+            try {
+                service.scaffold("Again", dimension, language);
+            } catch (const std::exception&) {
+                rejected = true;
+            }
+            require(rejected && read_text(project / "Scenes/main.scene.json") == marker,
+                    "Explicit creation rejects existing project without overwriting it");
+        }
+    }
+    editor::BuildConfig legacy;
+    legacy.project_root = root / "legacy";
+    legacy.engine_root = path_from_utf8(FASET_ENGINE_SOURCE);
+    editor::BuildService(legacy).scaffold("Legacy", 3);
+    require(!fs::exists(legacy.project_root / "Scenes/main.scene.json"),
+            "Two-argument scaffold retains its prior no-scene behavior");
+    const auto concurrent_root = root / "concurrent";
+    editor::BuildConfig concurrent;
+    concurrent.project_root = concurrent_root;
+    concurrent.engine_root = path_from_utf8(FASET_ENGINE_SOURCE);
+    editor::BuildService first(concurrent), second(concurrent);
+    std::atomic<int> ready = 0;
+    std::atomic<int> successes = 0;
+    auto attempt = [&](editor::BuildService& service, const char* name) {
+        ++ready;
+        while (ready.load() < 2)
+            std::this_thread::yield();
+        try {
+            service.scaffold(name, 2, "lua");
+            ++successes;
+        } catch (const std::exception&) {
+        }
+    };
+    std::thread a(attempt, std::ref(first), "First");
+    std::thread b(attempt, std::ref(second), "Second");
+    a.join();
+    b.join();
+    require(successes == 1, "Two concurrent creators publish exactly one starter");
+    const auto winner = read_json(concurrent_root / "project.faset.json");
+    require(winner.at("name") == "First" || winner.at("name") == "Second",
+            "Published manifest belongs to the successful creator");
+    require(fs::is_regular_file(concurrent_root / "Scripts/main.lua") &&
+                fs::is_regular_file(concurrent_root / "Scenes/main.scene.json"),
+            "The winning starter publishes all required files");
+    const auto ignore = read_text(concurrent_root / ".gitignore");
+    require(ignore.find("!.faset/lua/faset.lua") != std::string::npos,
+            "LuaLS declarations are commit-friendly in generated projects");
+}
 void lua_project_contracts(const fs::path& root) {
     fs::create_directories(root);
     require(!scripting::loadLuaProject(root).enabled(), "No manifest means no Lua dependency");
@@ -379,6 +479,7 @@ int test_main(int argc, char** argv) {
     try {
         fs::create_directories(temporary);
         lua_project_contracts(temporary / "lua-project");
+        starter_contracts(temporary / "starters");
         const auto original_executable = fs::absolute(path_from_utf8(argv[0]));
         const auto executable = temporary / original_executable.filename();
         fs::copy_file(original_executable, executable);

tests/editor_session_tests.cpp

@@ -1,9 +1,18 @@
 #include <faset/core/io.hpp>
 #include <faset/editor/session.hpp>
+#include <chrono>
 #include <iostream>
+#include <thread>
 
-int main() {
+int main(int argc, char** argv) {
     using namespace faset;
+    if (argc >= 3 && std::string_view(argv[1]) == "--editor-probe") {
+        Json arguments = Json::array();
+        for (int index = 3; index < argc; ++index)
+            arguments.push_back(argv[index]);
+        atomic_write_json(path_from_utf8(argv[2]), arguments);
+        return 0;
+    }
     const auto root = std::filesystem::temp_directory_path() /
                       path_from_utf8("Faset Café 世界 session " + new_id());
     try {
@@ -115,6 +124,32 @@ int main() {
                        {{"path", "Scripts/behavior.lua"}, {"editor", {"{file}"}}}, "lua.editor");
         reject_command("faset_script_open", {{"path", "Scripts/behavior.lua"}, {"editor", {""}}},
                        "lua.editor");
+        const auto probe = root / "editor-argv.json";
+        const auto opened = commands.call(
+            "faset_source_open",
+            {{"path", "Scripts/Gameplay.cpp"}, {"line", 17}, {"column", 4},
+             {"editor", Json::array({path_to_utf8(std::filesystem::absolute(path_from_utf8(argv[0]))),
+                                     "--editor-probe", path_to_utf8(probe),
+                                     "{file}:{line}:{column}", "{project}"})}});
+        for (int attempt = 0; attempt < 100 && !std::filesystem::exists(probe); ++attempt)
+            std::this_thread::sleep_for(std::chrono::milliseconds(10));
+        require(opened.at("path") == "Scripts/Gameplay.cpp" && opened.at("line") == 17 &&
+                    std::filesystem::is_regular_file(probe) &&
+                    read_json(probe) ==
+                        Json::array({path_to_utf8(root / "Scripts/Gameplay.cpp") + ":17:4",
+                                     path_to_utf8(root)}),
+                "test", "Source navigation passes a Unicode path and location as literal argv");
+        reject_command("faset_source_open", {{"path", "../outside.cpp"}}, "source.path");
+        reject_command("faset_source_open", {{"path", "Scripts/missing.cpp"}}, "source.path");
+        reject_command("faset_source_open", {{"path", "Scripts"}}, "source.path");
+        atomic_write(root / "Scripts/tool.exe", "not a source\n");
+        reject_command("faset_source_open", {{"path", "Scripts/tool.exe"}}, "source.path");
+        std::filesystem::create_directories(root / "Outside");
+        std::error_code link_error;
+        std::filesystem::create_symlink(root / "Outside/secret.cpp",
+                                        root / "Scripts/escape.cpp", link_error);
+        if (!link_error)
+            reject_command("faset_source_open", {{"path", "Scripts/escape.cpp"}}, "source.path");
         auto bad_lua_project = session.project();
         bad_lua_project["scripting"] = {{"lua", {{"scripts", {"Scripts/missing.lua"}}}}};
         atomic_write_json(root / "project.faset.json", bad_lua_project);

tests/editor_ui_launcher.cpp

@@ -111,6 +111,9 @@ int main() {
             text(launcher, "launcher-path", path_to_utf8(root / "." / new_project.filename()));
             click(launcher, "launcher-2d");
             check(launcher.widgets().find("launcher-2d")->selected, "2D project selection");
+            click(launcher, "launcher-lua");
+            check(launcher.widgets().find("launcher-lua")->selected,
+                  "Lua project language selection");
             renderer.render(launcher.snapshot());
             renderer.capture(root / "launcher-create.ppm");
             launcher.frame({key("Return", true)});
@@ -118,6 +121,7 @@ int main() {
                   "Create through keyboard rejected: " +
                       launcher.widgets().find("launcher-error")->text);
             check(launcher.selection()->create && launcher.selection()->dimension == 2 &&
+                      launcher.selection()->language == "lua" &&
                       launcher.selection()->name == "Тестовый проект",
                   "Create through keyboard preserves typed project metadata");
             check(launcher.selection()->path == new_project,
@@ -127,6 +131,19 @@ int main() {
             check(!std::filesystem::exists(new_project),
                   "Launcher does not create a partial project before Session scaffold");
         }
+        {
+            editor::ProjectSelection retry{new_project, "Retry starter", 3, true, "lua"};
+            editor::ProjectLauncher launcher(renderer, path_from_utf8(FASET_TEST_ENGINE), {},
+                                             recents, retry, "Template source is unavailable");
+            launcher.frame({});
+            check(launcher.widgets().find("launcher-create")->selected &&
+                      launcher.widgets().find("launcher-lua")->selected &&
+                      launcher.widgets().find("launcher-path")->text == path_to_utf8(new_project) &&
+                      launcher.widgets().find("launcher-name")->text == "Retry starter" &&
+                      launcher.widgets().find("launcher-error")->text ==
+                          "Template source is unavailable",
+                  "Failed starter returns to Create with the chosen options and error");
+        }
         {
             editor::ProjectLauncher launcher(renderer, path_from_utf8(FASET_TEST_ENGINE),
                                              root / "Missing", recents);

tests/render_gpu_shader_contract_tests.cpp

@@ -59,15 +59,6 @@ int main() {
         faset::atomic_write_json(reflection_file, metadata);
         must_reject([&] { (void)faset::render::detail::load_gpu_shader_bundle(temporary); },
                     "A consistently rehashed but incompatible GPU record stride must be rejected");
-        faset::atomic_write_json(reflection_file,
-                                 faset::read_json(original / "gpuPostCullMain.reflection.json"));
-        reflection_file = temporary / "gpuVertexMain.reflection.json";
-        metadata = faset::read_json(original / "gpuVertexMain.reflection.json");
-        metadata["layout"]["descriptors"][0]["set"] = 1;
-        metadata["layout_fingerprint"] = faset::sha256(metadata["layout"].dump());
-        faset::atomic_write_json(reflection_file, metadata);
-        must_reject([&] { (void)faset::render::detail::load_gpu_shader_bundle(temporary); },
-                    "GPU graphics scene buffers must stay in descriptor set two");
         fs::remove(temporary / "gpuHzbMain.spv");
         must_reject([&] { (void)faset::render::detail::load_gpu_shader_bundle(temporary); },
                     "Missing P2 entry must be rejected");

tests/render_lighting_policy_tests.cpp

@@ -1,191 +0,0 @@
-#include <faset/render/lighting.hpp>
-#include <algorithm>
-#include <array>
-#include <cmath>
-#include <iostream>
-#include <stdexcept>
-
-using namespace faset::render;
-namespace {
-void require(bool condition, const char* message) {
-    if (!condition)
-        throw std::runtime_error(message);
-}
-Snapshot fixture() {
-    Snapshot frame;
-    const Vec3 eye{0, 2, 8};
-    const auto view = look_at(eye, {0, 0, 0});
-    const auto projection = perspective(.9f, 16.f / 9.f, .1f, 120.f);
-    frame.eye = eye;
-    frame.view_projection = multiply(projection, view);
-    frame.projection = projection;
-    frame.camera_frustum = CameraFrustum{view, projection, .1f, 120.f, true};
-    frame.authored_lights_present = true;
-    frame.sun = SunLight{"sun", {-.7f, -.5f, -.3f}, {1, 1, 1, 1}, 1, true};
-    return frame;
-}
-LocalLight point_light(std::string id, int priority = 0) {
-    LocalLight light;
-    light.kind = LocalLight::Kind::Point;
-    light.stable_id = std::move(id);
-    light.position = {0, 2, 0};
-    light.range = 12;
-    light.shadow_priority = priority;
-    return light;
-}
-LocalLight spot_light(std::string id, int priority = 0) {
-    auto light = point_light(std::move(id), priority);
-    light.kind = LocalLight::Kind::Spot;
-    light.direction = {0, -1, 0};
-    return light;
-}
-bool contains_caster(const ShadowView& view, std::uint32_t draw_index) {
-    return std::find(view.caster_indices.begin(), view.caster_indices.end(), draw_index) !=
-           view.caster_indices.end();
-}
-void run() {
-    auto frame = fixture();
-    const auto plan = build_shadow_plan(frame, {}, {});
-    require(plan.sun_views.size() == 4 && plan.effective_sun_cascades == 4,
-            "Explicit camera receives four usable sun cascades");
-    require(plan.sun_views[0].split_near == .1f &&
-                std::abs(plan.sun_views.back().split_far - 80.f) < 1e-4f,
-            "Practical splits start at camera near and stop at shadow distance");
-    for (std::size_t i = 1; i < plan.sun_views.size(); ++i)
-        require(plan.sun_views[i].split_near == plan.sun_views[i - 1].split_far &&
-                    plan.sun_views[i].split_far > plan.sun_views[i].split_near,
-                "Cascade split endpoints are strictly increasing and contiguous");
-    require(plan.sun_views[0].tile_index == 0 && plan.sun_views[3].tile_index == 3 &&
-                plan.sun_views[0].usable_size == 1020,
-            "Four guarded 1024-square tiles fit a 2048-square sun atlas");
-    auto shifted = frame;
-    shifted.eye[0] += .00001f;
-    const auto shifted_view = look_at(shifted.eye, {.00001f, 0, 0});
-    shifted.camera_frustum->view = shifted_view;
-    shifted.view_projection = multiply(shifted.projection, shifted_view);
-    const auto stable = build_shadow_plan(shifted, {}, {});
-    require(stable.sun_views[0].snapped_center_x == plan.sun_views[0].snapped_center_x &&
-                stable.sun_views[0].snapped_center_y == plan.sun_views[0].snapped_center_y,
-            "Subtexel camera translation retains the snapped sun projection origin");
-    const auto sun_direction = frame.sun->direction;
-    const auto inv_length = 1.f / std::hypot(sun_direction[0], sun_direction[1], sun_direction[2]);
-    const Vec3 upstream{-sun_direction[0] * inv_length * 18,
-                        -sun_direction[1] * inv_length * 18,
-                        -sun_direction[2] * inv_length * 18};
-    const ShadowCasterBounds offscreen{{{upstream[0] - .5f, upstream[1] - .5f,
-                                          upstream[2] - .5f},
-                                         {upstream[0] + .5f, upstream[1] + .5f,
-                                          upstream[2] + .5f}}, 7};
-    const ShadowCasterBounds outside{{{999, 0, 0}, {1001, 2, 2}}, 8};
-    const std::array casters{offscreen, outside};
-    const auto with_casters = build_shadow_plan(frame, casters, {});
-    require(std::any_of(with_casters.sun_views.begin(), with_casters.sun_views.end(),
-                        [](const auto& view) { return contains_caster(view, 7); }),
-            "Offscreen upstream caster remains in a receiver's sun shadow view");
-    require(std::none_of(with_casters.sun_views.begin(), with_casters.sun_views.end(),
-                         [](const auto& view) { return contains_caster(view, 8); }),
-            "Caster outside every sun XY footprint is excluded");
-    std::vector<ShadowCasterBounds> many(4097, {{{-.1f, -.1f, -.1f}, {.1f, .1f, .1f}}, 0});
-    for (std::uint32_t i = 0; i < many.size(); ++i)
-        many[i].draw_index = i;
-    const auto overdraw = build_shadow_plan(frame, many, {});
-    require(overdraw.caster_draws <= 4096 &&
-                std::any_of(overdraw.sun_views.begin(), overdraw.sun_views.end(),
-                            [](const auto& view) {
-                                return !view.valid && view.reason == ShadowDropReason::CasterBudget &&
-                                       view.caster_indices.empty();
-                            }),
-            "A view with 4097 casters is skipped whole rather than partially rendered");
-    frame.sun.reset();
-    for (int i = 0; i < 15; ++i)
-        frame.local_lights.push_back(spot_light("spot-" + std::to_string(i), 10));
-    frame.local_lights.push_back(point_light("last-point"));
-    const auto capacity = build_shadow_plan(frame, {}, {});
-    require(capacity.local_faces_used == 15 && capacity.dropped_point_faces == 6 &&
-                capacity.local_faces_used <= 16 && capacity.caster_draws <= 4096,
-            "Insufficient room for six point faces drops the complete point shadow");
-    require(capacity.submitted_local_indices.size() == 16 &&
-                std::none_of(capacity.local_views.begin(), capacity.local_views.end(),
-                             [](const auto& view) { return view.light_id == "last-point"; }),
-            "Atlas overflow leaves the point light in the lighting list, unshadowed");
-    frame.local_lights = {point_light("omnidirectional")};
-    const ShadowCasterBounds positive_x{{{3, -.2f, -.2f}, {3.4f, .2f, .2f}}, 19};
-    const auto point_faces = build_shadow_plan(frame, std::array{positive_x}, {});
-    require(point_faces.local_views.size() == 6 &&
-                contains_caster(point_faces.local_views[0], 19) &&
-                !contains_caster(point_faces.local_views[1], 19),
-            "Point-light caster behind the opposite face is culled from that face");
-    frame.local_lights.clear();
-    for (int i = 0; i < 15; ++i)
-        frame.local_lights.push_back(spot_light("spot-" + std::to_string(i), 10));
-    frame.local_lights.push_back(point_light("last-point"));
-    auto reversed = frame;
-    std::reverse(reversed.local_lights.begin(), reversed.local_lights.end());
-    const auto reordered = build_shadow_plan(reversed, {}, {});
-    require(reordered.local_views.size() == capacity.local_views.size(),
-            "Reversing input lights preserves scheduled view count");
-    for (std::size_t i = 0; i < capacity.local_views.size(); ++i)
-        require(reordered.local_views[i].light_id == capacity.local_views[i].light_id &&
-                    reordered.local_views[i].tile_index == capacity.local_views[i].tile_index,
-                "Stable IDs preserve atlas assignments across input reordering");
-    frame.local_lights.clear();
-    for (int i = 0; i < 128; ++i) {
-        auto light = spot_light("ordinary-" + std::to_string(i));
-        light.casts_shadow = false;
-        frame.local_lights.push_back(light);
-    }
-    auto important = spot_light("late-high-priority", 5);
-    important.casts_shadow = false;
-    frame.local_lights.push_back(important);
-    const auto ranked = build_shadow_plan(frame, {}, {});
-    require(ranked.submitted_local_indices.size() == 128 &&
-                ranked.omitted_local_lights == 1 &&
-                ranked.submitted_local_indices.front() == 128,
-            "Submission selects all 128 by priority and reports one omitted light");
-    frame.local_lights.back().range = -1;
-    bool invalid_overflow_rejected = false;
-    try {
-        (void)build_shadow_plan(frame, {}, {});
-    } catch (const std::invalid_argument&) {
-        invalid_overflow_rejected = true;
-    }
-    require(invalid_overflow_rejected,
-            "All authored lights are validated even when beyond the submission cap");
-    frame.local_lights.clear();
-    frame.sun.reset();
-    const auto no_sun = build_shadow_plan(frame, {}, {});
-    require(no_sun.requested_sun_cascades == 0 && no_sun.sun_views.empty(),
-            "Authored lights suppress legacy sun even when none is enabled");
-    for (int i = 0; i < 20; ++i)
-        frame.local_lights.push_back(spot_light("over-cap-" + std::to_string(i)));
-    ShadowBudget relaxed;
-    relaxed.max_local_faces = 64;
-    relaxed.max_local_lights = 256;
-    const auto clamped = build_shadow_plan(frame, {}, relaxed);
-    require(clamped.local_faces_used == 16 && clamped.dropped_local_faces == 4,
-            "Fixed 4x4 local atlas never allocates outside its sixteen tiles");
-    frame = fixture();
-    frame.camera_frustum.reset();
-    const auto legacy = build_shadow_plan(frame, {}, {});
-    require(legacy.sun_views.size() == 1 && legacy.effective_sun_cascades == 1,
-            "A low-level snapshot without camera frustum uses one reported sun view");
-    frame = fixture();
-    ShadowBudget unsupported;
-    unsupported.sun_atlas_available = false;
-    const auto no_atlas = build_shadow_plan(frame, {}, unsupported);
-    require(no_atlas.effective_sun_cascades == 0 &&
-                no_atlas.dropped_sun_views == 4 &&
-                no_atlas.sun_views[0].reason == ShadowDropReason::Unavailable,
-            "Unsupported depth atlas yields an explicit unshadowed sun fallback");
-}
-} // namespace
-int main() {
-    try {
-        run();
-        std::cout << "Shadow planning, stable allocation, caster visibility, and budgets passed\n";
-        return 0;
-    } catch (const std::exception& error) {
-        std::cerr << error.what() << '\n';
-        return 1;
-    }
-}

tests/render_reload_tests.cpp

@@ -59,27 +59,6 @@ int main() {
         const auto original_reflection = read_text(bundle / "fragmentMain.reflection.json");
         const auto original_fingerprint = Json::parse(original_reflection).at("layout_fingerprint");
         render::validate_shader_bundle(bundle);
-        auto bad_lighting_stride = Json::parse(original_reflection);
-        auto& lighting_descriptors = bad_lighting_stride["layout"]["descriptors"];
-        bool found_local_buffer = false;
-        for (auto& descriptor : lighting_descriptors)
-            if (descriptor["set"] == 1 && descriptor["binding"] == 1) {
-                descriptor["element_stride"] = 96;
-                found_local_buffer = true;
-            }
-        require(found_local_buffer, "Lighting stride fixture exists");
-        bad_lighting_stride["layout_fingerprint"] =
-            sha256(bad_lighting_stride["layout"].dump());
-        atomic_write_json(bundle / "fragmentMain.reflection.json", bad_lighting_stride);
-        bool rejected_lighting_stride = false;
-        try {
-            render::validate_shader_bundle(bundle);
-        } catch (const std::exception&) {
-            rejected_lighting_stride = true;
-        }
-        require(rejected_lighting_stride,
-                "Rehashed incompatible local-light element stride must be rejected");
-        atomic_write(bundle / "fragmentMain.reflection.json", original_reflection);
         render::RendererConfig configuration;
         configuration.width = configuration.height = 64;
         configuration.headless = true;
@@ -182,18 +161,6 @@ int main() {
         atomic_write(bundle / "fragmentMain.spv", "damaged bytecode");
         retained();
         restore();
-        auto incompatible = original_source;
-        auto at = incompatible.find("    float4 reserved;");
-        require(at != std::string::npos, "Local-light stride fixture exists");
-        incompatible.replace(at, std::string("    float4 reserved;").size(),
-                             "    float4 reserved;\n    float4 incompatibleExtraLane;");
-        atomic_write(source, incompatible);
-        require(compile(source, bundle) == 0, "Compile incompatible light-buffer stride");
-        require(read_json(bundle / "fragmentMain.reflection.json").at("layout_fingerprint") !=
-                    original_fingerprint,
-                "Lighting stride edit changes normalized layout fingerprint");
-        retained();
-        restore();
         auto malformed = original_spirv;
         for (int i = 0; i < 4; ++i)
             malformed[20 + i] = 0; // zero-word SPIR-V instruction
@@ -203,8 +170,8 @@ int main() {
         atomic_write_json(bundle / "fragmentMain.reflection.json", metadata);
         retained();
         restore();
-        incompatible = original_source;
-        at = incompatible.find("[[vk::binding(2,0)]]");
+        auto incompatible = original_source;
+        auto at = incompatible.find("[[vk::binding(2,0)]]");
         require(at != std::string::npos, "Shader descriptor fixture exists");
         incompatible.replace(at, std::string("[[vk::binding(2,0)]]").size(),
                              "[[vk::binding(7,0)]]");

tests/render_tests.cpp

@@ -134,102 +134,6 @@ int main(int argc, char** argv) {
         renderer.render(scene);
         pixels = renderer.pixels();
         require(pixels[index + 2] > 220, "Texture revision upload");
-        Snapshot two_lights;
-        two_lights.eye = {0, 0, 6};
-        two_lights.projection = perspective(.85f, 320.f / 240.f, .1f, 30.f);
-        two_lights.view_projection =
-            multiply(two_lights.projection, look_at(two_lights.eye, {0, 0, 0}));
-        two_lights.authored_lights_present = true;
-        two_lights.draws.push_back(
-            {cube_mesh(), transform({-1.4f, 0, 0}), {.5f, .5f, .5f, 1}, .6f, 0, false});
-        two_lights.draws.back().instance_key = "left-light-receiver";
-        two_lights.draws.push_back(
-            {cube_mesh(), transform({1.4f, 0, 0}), {.5f, .5f, .5f, 1}, .6f, 0, false});
-        two_lights.draws.back().instance_key = "right-light-receiver";
-        two_lights.ui_quads.push_back({8, 8, 40, 20, {.8f, .1f, .15f, 1}});
-        for (auto mode : {VisibilityMode::Direct, VisibilityMode::GpuFrustum}) {
-            renderer.set_visibility_mode(mode);
-            renderer.render(two_lights);
-            const auto dark = renderer.pixels();
-            require(renderer.stats().validation_errors == 0,
-                    "Zero-local-light descriptors are initialized");
-            auto legacy_lights = two_lights;
-            legacy_lights.authored_lights_present = false;
-            renderer.render(legacy_lights);
-            const auto legacy = renderer.pixels();
-            const auto left = (120 * 320 + 99) * 4;
-            require(legacy[left] > dark[left] + 15,
-                    "Authored-light presence suppresses the legacy sun even without a local light");
-            two_lights.local_lights = {
-                {LocalLight::Kind::Point, "red", {-1.4f, 0, 1.4f}, {0, 0, -1},
-                 {1, 0, 0, 1}, 8, 2.2f, .35f, .7f, false, 0},
-                {LocalLight::Kind::Point, "blue", {1.4f, 0, 1.4f}, {0, 0, -1},
-                {0, 0, 1, 1}, 8, 2.5f, .35f, .7f, false, 0}};
-            renderer.render(two_lights);
-            const auto lit = renderer.pixels();
-            const auto right = (120 * 320 + 221) * 4;
-            const auto ui = (10 * 320 + 10) * 4;
-            require(lit[left] > dark[left] + 20 && lit[right + 2] > dark[right + 2] + 20,
-                    "Separated red and blue point lights illuminate their receivers");
-            require(std::abs(int(lit[left + 2]) - int(dark[left + 2])) < 6 &&
-                        std::abs(int(lit[right]) - int(dark[right])) < 6,
-                    "Local light range keeps the opposite colored light off each receiver");
-            for (int channel = 0; channel < 4; ++channel)
-                require(lit[ui + channel] == dark[ui + channel],
-                        "Lighting changes leave UI tint unchanged");
-            require(renderer.stats().validation_errors == 0,
-                    "Direct and GPU local lighting report no Vulkan errors");
-            if (mode == VisibilityMode::GpuFrustum)
-                require(renderer.stats().effective_visibility_mode == VisibilityMode::GpuFrustum,
-                        "Local light image test actually exercises the GPU visibility path");
-            two_lights.local_lights[1].kind = LocalLight::Kind::Spot;
-            renderer.render(two_lights);
-            const auto aimed = renderer.pixels();
-            two_lights.local_lights[1].direction = {1, 0, 0};
-            renderer.render(two_lights);
-            const auto turned = renderer.pixels();
-            require(aimed[right + 2] > turned[right + 2] + 20,
-                    "Spotlight cone direction changes receiver illumination");
-            two_lights.local_lights.clear();
-        }
-        renderer.set_visibility_mode(VisibilityMode::Direct);
-        renderer.render(two_lights);
-        const auto unlit_overflow = renderer.pixels();
-        for (int i = 0; i < 128; ++i) {
-            LocalLight local;
-            local.stable_id = "low-priority-" + std::to_string(i);
-            local.position = {20, 20, 20};
-            local.range = 1;
-            local.intensity = 0;
-            local.casts_shadow = false;
-            two_lights.local_lights.push_back(local);
-        }
-        LocalLight high;
-        high.stable_id = "last-high-priority";
-        high.position = {-1.4f, 0, 1.4f};
-        high.color = {1, 0, 0, 1};
-        high.range = 2.2f;
-        high.intensity = 8;
-        high.shadow_priority = 10;
-        high.casts_shadow = false;
-        two_lights.local_lights.push_back(high);
-        two_lights.local_lights.back().range = -1;
-        bool overflow_validation_failed = false;
-        try {
-            renderer.render(two_lights);
-        } catch (const std::invalid_argument&) {
-            overflow_validation_failed = true;
-        }
-        require(overflow_validation_failed,
-                "Renderer validates light records beyond the 128-light cap");
-        two_lights.local_lights.back().range = 2.2f;
-        renderer.render(two_lights);
-        const auto ranked_pixels = renderer.pixels();
-        const auto ranked_left = (120 * 320 + 99) * 4;
-        require(renderer.stats().submitted_local_lights == 128 &&
-                    renderer.stats().omitted_local_lights == 1 &&
-                    ranked_pixels[ranked_left] > unlit_overflow[ranked_left] + 20,
-                "High-priority last light is submitted and omitted count is observable");
         if (argc > 2)
             renderer.capture(argv[2]);
         renderer.resize(400, 300);

tests/runtime_player_tests.cpp

@@ -1,12 +1,10 @@
 #include <bit>
-#include <algorithm>
 #include <cmath>
 #include <faset/assets/asset_pipeline.hpp>
 #include <faset/core/io.hpp>
 #include <faset/player/SceneView.hpp>
 #include <faset/runtime/Runtime.hpp>
 #include <iostream>
-#include <limits>
 #include <numbers>
 #include <stdexcept>
 
@@ -25,137 +23,12 @@ template <class F> void rejects(F&& function, const char* message) {
     }
     check(caught, message);
 }
-template <class F>
-void rejectsContaining(F&& function, std::string_view entityId, std::string_view field) {
-    try {
-        function();
-    } catch (const std::exception& error) {
-        const std::string_view what(error.what());
-        check(what.find(entityId) != std::string_view::npos &&
-                  what.find(field) != std::string_view::npos,
-              "Invalid light reports entity and field");
-        return;
-    }
-    throw std::runtime_error("Invalid light was accepted");
-}
 Json component(std::string type, Json fields) {
     return {{"id", type}, {"type", type}, {"version", 1}, {"fields", fields}};
 }
 Json entity(std::string id, Json parent, Json components) {
     return {{"id", id}, {"name", id}, {"parent", parent}, {"components", components}};
 }
-void lightingExtraction(faset::player::SceneView& view) {
-    auto scene = Json{{"format", "faset.scene"},
-                      {"version", 1},
-                      {"id", "lighting"},
-                      {"name", "Lighting"},
-                      {"dimension", 3},
-                      {"instances", Json::array()},
-                      {"entities", Json::array()}};
-    const auto empty = view.build(scene, 16.f / 9.f);
-    check(!empty.authored_lights_present && !empty.sun && empty.local_lights.empty(),
-          "Scene with no lights leaves legacy sun fallback available");
-    check(empty.camera_frustum && empty.camera_frustum->perspective &&
-              empty.camera_frustum->near_plane > 0 &&
-              empty.camera_frustum->far_plane > empty.camera_frustum->near_plane &&
-              faset::render::multiply(empty.camera_frustum->projection,
-                                      empty.camera_frustum->view) == empty.view_projection,
-          "3D extraction retains an unjittered camera frustum");
-    scene["entities"] = Json::array({
-        entity("sun", nullptr,
-               Json::array({component("faset.transform", {{"rotation", {0, .4, 0}}}),
-                            component("faset.light", {{"kind", "directional"},
-                                                      {"color", {1, .8, .6, 1}},
-                                                      {"intensity", 2.5},
-                                                      {"casts_shadow", false}})})),
-        entity("point", nullptr,
-               Json::array({component("faset.transform", {{"position", {2, 3, 4}}}),
-                            component("faset.light", {{"kind", "point"},
-                                                      {"color", {1, 0, 0, 1}},
-                                                      {"intensity", 4},
-                                                      {"range", 6},
-                                                      {"shadow_priority", 3}})})),
-        entity("spot", nullptr,
-               Json::array({component("faset.transform", {{"position", {-2, 1, 0}}}),
-                            component("faset.light", {{"kind", "spot"},
-                                                      {"color", {0, 0, 1, 1}},
-                                                      {"intensity", 3},
-                                                      {"range", 8},
-                                                      {"inner_angle", .2},
-                                                      {"outer_angle", .6}})}))});
-    const auto a = view.build(scene, 16.f / 9.f);
-    check(a.authored_lights_present && a.sun && a.local_lights.size() == 2,
-          "Directional, point, and spot lights survive extraction");
-    check(a.sun->color[1] == .8f && a.sun->intensity == 2.5f && !a.sun->casts_shadow,
-          "Authored sun properties survive extraction");
-    check(a.local_lights[0].kind == faset::render::LocalLight::Kind::Point &&
-              a.local_lights[0].position == faset::render::Vec3{2, 3, 4} &&
-              a.local_lights[0].range == 6 && a.local_lights[0].shadow_priority == 3,
-          "Point fields and transform survive extraction");
-    check(a.local_lights[1].kind == faset::render::LocalLight::Kind::Spot &&
-              a.local_lights[1].inner_angle == .2f && a.local_lights[1].outer_angle == .6f,
-          "Spot cone survives extraction");
-    std::reverse(scene["entities"].begin(), scene["entities"].end());
-    const auto b = view.build(scene, 16.f / 9.f);
-    check(a.sun->stable_id == b.sun->stable_id &&
-              a.local_lights[0].stable_id == b.local_lights[0].stable_id &&
-              a.local_lights[1].stable_id == b.local_lights[1].stable_id,
-          "Light identity and ordering ignore entity array order");
-    scene["entities"].erase(scene["entities"].begin() + 2);
-    const auto localOnly = view.build(scene, 1);
-    check(localOnly.authored_lights_present && !localOnly.sun &&
-              localOnly.local_lights.size() == 2,
-          "Local-only lighting does not synthesize a sun");
-    scene["entities"] = Json::array({entity(
-        "disabled-sun", nullptr,
-        Json::array({component("faset.light", {{"kind", "directional"}, {"enabled", false}})}))});
-    const auto disabled = view.build(scene, 1);
-    check(disabled.authored_lights_present && !disabled.sun && disabled.local_lights.empty(),
-          "Explicit disabled sun suppresses legacy fallback");
-    scene["entities"][0]["components"][0]["version"] = 2;
-    const auto future = view.build(scene, 1);
-    check(future.authored_lights_present && !future.sun,
-          "Opaque future-version light still suppresses legacy fallback");
-    scene["entities"] = Json::array({
-        entity("sun-z", nullptr, Json::array({component("faset.light", Json::object())})),
-        entity("sun-a", nullptr, Json::array({component("faset.light", Json::object())}))});
-    const auto twoSuns = view.build(scene, 1);
-    check(twoSuns.sun && twoSuns.sun->stable_id.find("sun-a") != std::string::npos,
-          "Multiple suns select lowest stable identity");
-    check(!view.diagnostics().empty() &&
-              view.diagnostics().front().find("directional") != std::string::npos,
-          "Additional directionals produce an actionable diagnostic");
-    scene["entities"] = Json::array({entity(
-        "bad-light", nullptr,
-        Json::array({component("faset.light", {{"kind", "point"}, {"range", 0}})}))});
-    rejectsContaining([&] { view.build(scene, 1); }, "bad-light", "range");
-    scene["entities"][0]["components"][0]["fields"] =
-        {{"kind", "spot"}, {"range", 10}, {"inner_angle", .8}, {"outer_angle", .2}};
-    rejectsContaining([&] { view.build(scene, 1); }, "bad-light", "inner_angle");
-    scene["entities"][0]["components"][0]["fields"] = {{"kind", "area"}};
-    rejectsContaining([&] { view.build(scene, 1); }, "bad-light", "kind");
-    scene["entities"][0]["components"][0]["fields"] =
-        {{"kind", "point"}, {"shadow_priority", std::int64_t{2147483648}}};
-    rejectsContaining([&] { view.build(scene, 1); }, "bad-light", "shadow_priority");
-    scene["entities"][0]["components"][0]["fields"] = {{"kind", "point"}};
-    scene["entities"][0]["components"].insert(
-        scene["entities"][0]["components"].begin(),
-        component("faset.transform", {{"scale", {1, 1, 0}}}));
-    const auto flatPoint = view.build(scene, 1);
-    check(flatPoint.local_lights.size() == 1 &&
-              flatPoint.local_lights[0].kind == faset::render::LocalLight::Kind::Point,
-          "Point light accepts a zero Z scale because it needs only a position");
-    scene["entities"][0]["components"].erase(scene["entities"][0]["components"].begin());
-    scene["entities"][0]["components"][0]["fields"] =
-        {{"kind", "point"},
-         {"color", Json::array({1, std::numeric_limits<double>::quiet_NaN(), 1, 1})}};
-    rejectsContaining([&] { view.build(scene, 1); }, "bad-light", "color");
-    scene["entities"][0]["components"].insert(
-        scene["entities"][0]["components"].begin(),
-        component("faset.transform", {{"position", {0, 0, 0}},
-                                       {"scale", Json::array({1, std::numeric_limits<double>::quiet_NaN(), 1})}}));
-    rejectsContaining([&] { view.build(scene, 1); }, "bad-light", "transform");
-}
 void physicsDebug(faset::player::SceneView& view) {
     for (int dimension : {2, 3}) {
         const std::string bodyName = dimension == 2 ? "rigid_body_2d" : "rigid_body_3d";
@@ -286,7 +159,6 @@ void run() {
     faset::atomic_write(folder / "version.fscene", version);
     rejects([&] { faset::player::readScene(folder / "version.fscene"); }, "reject cooked version");
     faset::player::SceneView view(folder);
-    lightingExtraction(view);
     physicsDebug(view);
     auto snapshot = view.build(scene, 16.f / 9.f);
     check(snapshot.draws.size() == 1, "SceneView builtin mesh");

tests/test_p3_lighting_benchmark.py

@@ -1,229 +0,0 @@
-"""Contract and arithmetic tests for the offline P3 lighting sweep wrapper."""
-
-import csv
-import json
-import subprocess
-import sys
-import tempfile
-import unittest
-from pathlib import Path
-
-
-ROOT = Path(__file__).resolve().parents[1]
-SCRIPT = ROOT / "tools/benchmark_p3_lighting.py"
-sys.path.insert(0, str(ROOT / "tools"))
-
-
-def sample(shadows, visibility, lights, raster, gpu, repeat=1, frame=0):
-    return {
-        "shadows": shadows, "visibility": visibility, "light_count": str(lights),
-        "run_index": str(repeat), "frame": str(frame),
-        "gpu_main_raster_ms": str(raster), "gpu_ms": str(gpu),
-        "gpu_shadow_ms": "0", "cpu_ms": "1", "readback_cpu_ms": ".5",
-        "validation_errors": "0", "device": "Fake GPU", "driver": "Fake Driver",
-        "commit": "abc123", "effective_visibility": visibility,
-        "lighting_path": "forward", "submitted_local_lights": str(lights),
-        "omitted_local_lights": "0", "shadow_tiles": "0", "draw_calls": "1",
-        "gpu_bytes": "4096", "validation_enabled": "0", "width": "1920", "height": "1080",
-    }
-
-
-FAKE_BENCHMARK = r'''import argparse
-import csv
-import json
-from pathlib import Path
-
-p = argparse.ArgumentParser()
-for flag in ("lights", "run-index", "width", "height", "warmup", "frames"):
-    p.add_argument("--" + flag, type=int, required=True)
-for flag in ("shadows", "visibility", "csv", "commit", "validation"):
-    p.add_argument("--" + flag, required=True)
-p.add_argument("--driver")
-a = p.parse_args()
-path = Path(a.csv)
-path.with_suffix(".args.json").write_text(json.dumps(vars(a)), encoding="utf-8")
-fieldnames = ["light_count", "shadows", "visibility", "frame", "device", "driver",
-              "commit", "gpu_main_raster_ms", "gpu_ms", "gpu_shadow_ms", "cpu_ms",
-              "readback_cpu_ms", "validation_errors", "run_index", "effective_visibility",
-              "lighting_path", "submitted_local_lights", "omitted_local_lights",
-              "shadow_tiles", "draw_calls", "gpu_bytes", "validation_enabled", "width", "height"]
-with path.open("w", newline="", encoding="utf-8") as stream:
-    writer = csv.DictWriter(stream, fieldnames=fieldnames)
-    writer.writeheader()
-    for frame in range(a.frames):
-        writer.writerow(dict(light_count=a.lights, shadows=a.shadows,
-                             visibility=a.visibility, frame=frame, device="Fake GPU",
-                             driver="Fake Driver", commit=a.commit,
-                             gpu_main_raster_ms=.4 + .02 * a.lights, gpu_ms=4 + .02 * a.lights,
-                             gpu_shadow_ms=0, cpu_ms=1, readback_cpu_ms=.5,
-                             validation_errors=0, run_index=a.run_index,
-                             effective_visibility=a.visibility, lighting_path="forward",
-                             submitted_local_lights=a.lights, omitted_local_lights=0,
-                             shadow_tiles=0, draw_calls=1, gpu_bytes=4096,
-                             validation_enabled=0, width=a.width, height=a.height))
-'''
-
-
-class LightingBenchmarkTests(unittest.TestCase):
-    def test_list_runs_has_three_independent_repeats_for_each_shadow_setting(self):
-        process = subprocess.run([sys.executable, SCRIPT, "--list-runs"],
-                                 text=True, capture_output=True, check=True)
-        runs = json.loads(process.stdout)["runs"]
-        self.assertEqual(len(runs), 108)
-        for shadows in ("off", "on"):
-            group = [run for run in runs if run["shadows"] == shadows]
-            self.assertEqual(len(group), 54)
-            self.assertEqual({(run["light_count"], run["visibility"])
-                              for run in group},
-                             {(light, mode) for light in (0, 4, 16, 32, 64, 128)
-                              for mode in ("direct", "gpu-frustum", "gpu-occlusion")})
-            self.assertEqual({(run["light_count"], run["visibility"], run["repeat"])
-                              for run in group},
-                             {(light, mode, repeat)
-                              for light in (0, 4, 16, 32, 64, 128)
-                              for mode in ("direct", "gpu-frustum", "gpu-occlusion")
-                              for repeat in (1, 2, 3)})
-
-    def test_gate_uses_per_run_medians_and_same_mode_shadow_baseline(self):
-        from benchmark_p3_lighting import summarize_rows
-
-        rows = []
-        for repeat in (1, 2, 3):
-            for frame in (0, 1, 2):
-                rows.append(sample("off", "direct", 0, .5, 10, repeat, frame))
-                rows.append(sample("off", "direct", 32,
-                                   100 if repeat == 3 else 1.5, 11, repeat, frame))
-                rows.append(sample("on", "gpu-frustum", 0, .5, 4, repeat, frame))
-                rows.append(sample("on", "gpu-frustum", 64, 1.1, 4.6, repeat, frame))
-                rows.append(sample("off", "gpu-occlusion", 0, .5, 4, repeat, frame))
-                rows.append(sample("off", "gpu-occlusion", 128, 1.09, 4.59, repeat, frame))
-        summary = summarize_rows(rows)
-        hits = {(item["shadows"], item["visibility"], item["light_count"]): item
-                for item in summary["forward_plus_gate"]["candidates"]}
-        self.assertEqual(set(hits), {("off", "direct", 32),
-                                     ("on", "gpu-frustum", 64)})
-        self.assertAlmostEqual(hits[("off", "direct", 32)]["overhead_ms"], 1.0)
-        self.assertAlmostEqual(hits[("on", "gpu-frustum", 64)]["overhead_ms"], .6)
-        self.assertEqual(hits[("off", "direct", 32)]["zero_light_gpu_ms"], 10)
-        self.assertEqual(hits[("on", "gpu-frustum", 64)]["zero_light_gpu_ms"], 4)
-
-    def test_sweep_runs_fake_executable_and_preserves_all_raw_frames(self):
-        with tempfile.TemporaryDirectory() as temporary:
-            root = Path(temporary)
-            fake = root / "fake_benchmark.py"
-            fake.write_text(FAKE_BENCHMARK, encoding="utf-8")
-            output = root / "café 世界"
-            process = subprocess.run(
-                [sys.executable, SCRIPT, "--sweep", "--executable", fake,
-                 "--output", output, "--shadows", "off", "--commit", "abc123",
-                 "--driver", "Fake Driver"],
-                text=True, capture_output=True)
-            self.assertEqual(process.returncode, 0, process.stderr)
-            raw = list((output / "raw").glob("*.csv"))
-            self.assertEqual(len(raw), 54)
-            with (output / "merged.csv").open(newline="", encoding="utf-8") as stream:
-                merged = list(csv.DictReader(stream))
-            self.assertEqual(len(merged), 54 * 30)
-            self.assertEqual({row["source_csv"] for row in merged},
-                             {path.name for path in raw})
-            report = json.loads((output / "summary.json").read_text(encoding="utf-8"))
-            self.assertEqual(report["runs_completed"], 54)
-            self.assertEqual(report["rows"], 54 * 30)
-            self.assertTrue(report["forward_plus_gate"]["triggered"])
-            one = json.loads(next((output / "raw").glob("*.args.json")).read_text())
-            self.assertEqual((one["width"], one["height"], one["warmup"], one["frames"]),
-                             (1920, 1080, 10, 30))
-            self.assertEqual(one["validation"], "off")
-
-    def test_sweep_rejects_missing_gpu_raster_column(self):
-        with tempfile.TemporaryDirectory() as temporary:
-            root = Path(temporary)
-            fake = root / "bad_benchmark.py"
-            fake.write_text(FAKE_BENCHMARK.replace(
-                '"gpu_main_raster_ms", "gpu_ms"', '"gpu_ms"').replace(
-                'gpu_main_raster_ms=.4 + .02 * a.lights, ', ''), encoding="utf-8")
-            output = root / "invalid"
-            process = subprocess.run(
-                [sys.executable, SCRIPT, "--sweep", "--executable", fake,
-                 "--output", output, "--shadows", "off", "--commit", "abc123",
-                 "--driver", "Fake Driver"],
-                text=True, capture_output=True)
-            self.assertNotEqual(process.returncode, 0)
-            self.assertIn("gpu_main_raster_ms", process.stderr)
-            self.assertFalse((output / "summary.json").exists())
-
-    def test_sweep_rejects_visibility_fallback_as_a_mode_measurement(self):
-        with tempfile.TemporaryDirectory() as temporary:
-            root = Path(temporary)
-            fake = root / "fallback.py"
-            fake.write_text(FAKE_BENCHMARK.replace(
-                'effective_visibility=a.visibility', 'effective_visibility="direct"'),
-                encoding="utf-8")
-            output = root / "fallback-output"
-            process = subprocess.run(
-                [sys.executable, SCRIPT, "--sweep", "--executable", fake,
-                 "--output", output, "--shadows", "off", "--commit", "abc123",
-                 "--driver", "Fake Driver"],
-                text=True, capture_output=True)
-            self.assertNotEqual(process.returncode, 0)
-            self.assertIn("effective_visibility", process.stderr)
-            self.assertFalse((output / "summary.json").exists())
-
-    def test_sweep_rejects_a_scene_that_does_not_submit_requested_lights(self):
-        with tempfile.TemporaryDirectory() as temporary:
-            root = Path(temporary)
-            fake = root / "wrong-count.py"
-            fake.write_text(FAKE_BENCHMARK.replace(
-                'submitted_local_lights=a.lights', 'submitted_local_lights=0'),
-                encoding="utf-8")
-            output = root / "wrong-count-output"
-            process = subprocess.run(
-                [sys.executable, SCRIPT, "--sweep", "--executable", fake,
-                 "--output", output, "--shadows", "off", "--commit", "abc123",
-                 "--driver", "Fake Driver"],
-                text=True, capture_output=True)
-            self.assertNotEqual(process.returncode, 0)
-            self.assertIn("submitted_local_lights", process.stderr)
-            self.assertFalse((output / "summary.json").exists())
-
-    def test_sweep_requires_known_driver_identity(self):
-        from benchmark_p3_lighting import sweep
-        with tempfile.TemporaryDirectory() as temporary:
-            fake = Path(temporary) / "fake.py"
-            fake.write_text(FAKE_BENCHMARK, encoding="utf-8")
-            with self.assertRaisesRegex(ValueError, "--driver"):
-                sweep(fake, Path(temporary) / "out", "off", "abc123")
-
-
-def real_executable_smoke(executable: Path) -> None:
-    from benchmark_p3_lighting import REQUIRED_COLUMNS
-
-    choices = subprocess.run([executable, "--list-runs"], capture_output=True,
-                             text=True, check=True)
-    declared = json.loads(choices.stdout)
-    if declared["lights"] != [0, 4, 16, 32, 64, 128] or len(declared["visibility"]) != 3:
-        raise AssertionError("C++ executable and Python sweep matrix disagree")
-    with tempfile.TemporaryDirectory() as directory:
-        output = Path(directory) / "café 世界" / "smoke.csv"
-        subprocess.run([executable, "--lights", "4", "--shadows", "off",
-                        "--visibility", "direct", "--width", "64", "--height", "64",
-                        "--warmup", "0", "--frames", "1", "--validation", "on",
-                        "--commit", "smoke", "--driver", "smoke-driver",
-                        "--csv", output], capture_output=True, text=True, check=True)
-        with output.open(newline="", encoding="utf-8") as stream:
-            reader = csv.DictReader(stream)
-            columns, rows = reader.fieldnames or [], list(reader)
-        if set(REQUIRED_COLUMNS) - set(columns) or len(rows) != 1:
-            raise AssertionError("Real benchmark CSV lacks a complete single-frame row")
-        row = rows[0]
-        if (row["effective_visibility"] != "direct" or row["lighting_path"] != "forward" or
-                row["submitted_local_lights"] != "4" or row["validation_errors"] != "0" or
-                float(row["gpu_main_raster_ms"]) <= 0):
-            raise AssertionError("Real benchmark did not report the measured lighting path")
-
-
-if __name__ == "__main__":
-    if len(sys.argv) == 3 and sys.argv[1] == "--real-executable":
-        real_executable_smoke(Path(sys.argv[2]).resolve())
-    else:
-        unittest.main()

tests/test_shader_reflection.py

@@ -36,35 +36,6 @@ def parameter(name: str, index: int, shape: str, access: str, stride: int | None
 
 
 class ReflectionTests(unittest.TestCase):
-    def test_graphics_lighting_abi(self):
-        compiler = os.environ["FASET_TEST_SLANGC"]
-        with tempfile.TemporaryDirectory(prefix="faset-lighting-abi-") as directory:
-            for source, entry, defines in (
-                ("baseline.slang", "fragmentMain", []),
-                ("gpu_scene.slang", "gpuVertexMain", ["--define", "FASET_GPU_GRAPHICS=1"]),
-            ):
-                process = subprocess.run(
-                    [sys.executable, str(SCRIPT), "--compiler", compiler, "--source",
-                     str(SCRIPT.parents[1] / "shaders" / source), "--entry", entry,
-                     *defines, "--output", directory],
-                    capture_output=True, text=True,
-                )
-                self.assertEqual(process.returncode, 0, process.stderr)
-            fragment = json.loads((Path(directory) / "fragmentMain.reflection.json").read_text())
-            gpu_vertex = json.loads((Path(directory) / "gpuVertexMain.reflection.json").read_text())
-            lighting = {
-                (d["set"], d["binding"]): (d["type"], d.get("element_stride"))
-                for d in fragment["layout"]["descriptors"]
-            }
-            self.assertEqual([lighting[1, i] for i in range(4)],
-                             [("storage_buffer", 80), ("storage_buffer", 80),
-                              ("storage_buffer", 112), ("sampled_image_2d", None)])
-            graphics = {
-                (d["set"], d["binding"]): d["element_stride"]
-                for d in gpu_vertex["layout"]["descriptors"]
-            }
-            self.assertEqual([graphics[2, i] for i in range(3)], [224, 4, 208])
-
     def test_gpu_vertex_paths_do_not_require_shader_draw_parameters(self):
         # SV_InstanceID makes Slang subtract BaseInstance and emit DrawParameters.
         # Our indirect commands always use firstInstance=0, so the Vulkan instance

tools/benchmark_p3_lighting.py

@@ -1,262 +0,0 @@
-#!/usr/bin/env python3
-"""Run the fixed P3 lighting sweep and retain raw per-frame GPU measurements.
-
-The Forward+ threshold in the summary is a measurement result, not an automatic
-renderer switch. Apply it to the Linux physical reference GPU; keep other devices
-as separate functional/performance observations.
-"""
-from __future__ import annotations
-
-import argparse
-import csv
-import json
-import math
-from pathlib import Path
-import statistics
-import subprocess
-import sys
-
-
-LIGHT_COUNTS = (0, 4, 16, 32, 64, 128)
-VISIBILITY_MODES = ("direct", "gpu-frustum", "gpu-occlusion")
-REPEATS = (1, 2, 3)
-WARMUP_FRAMES = 10
-MEASURED_FRAMES = 30
-WIDTH, HEIGHT = 1920, 1080
-REQUIRED_COLUMNS = (
-    "light_count", "shadows", "visibility", "frame", "device", "driver",
-    "commit", "gpu_main_raster_ms", "gpu_ms", "gpu_shadow_ms", "cpu_ms",
-    "readback_cpu_ms", "validation_errors", "run_index", "effective_visibility",
-    "lighting_path", "submitted_local_lights", "omitted_local_lights",
-    "shadow_tiles", "draw_calls", "gpu_bytes", "validation_enabled", "width", "height",
-)
-TIMING_COLUMNS = ("gpu_main_raster_ms", "gpu_ms", "gpu_shadow_ms", "cpu_ms",
-                  "readback_cpu_ms")
-
-
-def build_runs(shadows: str = "both") -> list[dict]:
-    if shadows not in ("off", "on", "both"):
-        raise ValueError(f"Unsupported shadow setting: {shadows}")
-    settings = ("off", "on") if shadows == "both" else (shadows,)
-    return [{"shadows": shadow, "visibility": mode, "light_count": lights,
-             "repeat": repeat}
-            for shadow in settings for mode in VISIBILITY_MODES
-            for lights in LIGHT_COUNTS for repeat in REPEATS]
-
-
-def median(values: list[float]) -> float:
-    if not values:
-        raise ValueError("Cannot summarize empty measurements")
-    return float(statistics.median(values))
-
-
-def p95(values: list[float]) -> float:
-    if not values:
-        raise ValueError("Cannot summarize empty measurements")
-    ordered = sorted(values)
-    return ordered[math.ceil(.95 * len(ordered)) - 1]
-
-
-def _measurement(row: dict, name: str) -> float:
-    try:
-        value = float(row[name])
-    except (KeyError, TypeError, ValueError) as error:
-        raise ValueError(f"Invalid {name} in benchmark CSV") from error
-    if not math.isfinite(value) or value < 0:
-        raise ValueError(f"Invalid {name} in benchmark CSV: {value}")
-    return value
-
-
-def summarize_rows(rows: list[dict]) -> dict:
-    """Use the median of each independent run's median, then compare like baselines."""
-    grouped: dict[tuple[str, str, int], dict[int, list[dict]]] = {}
-    for row in rows:
-        try:
-            key = (row["shadows"], row["visibility"], int(row["light_count"]))
-            repeat = int(row["run_index"])
-        except (KeyError, TypeError, ValueError) as error:
-            raise ValueError("Benchmark row lacks shadow/mode/light/repeat identity") from error
-        if key[0] not in ("off", "on") or key[1] not in VISIBILITY_MODES or repeat < 1:
-            raise ValueError(f"Invalid benchmark configuration: {key}, repeat {repeat}")
-        for name in TIMING_COLUMNS:
-            _measurement(row, name)
-        grouped.setdefault(key, {}).setdefault(repeat, []).append(row)
-
-    configurations = []
-    lookup = {}
-    for (shadows, visibility, lights), repeats in sorted(grouped.items()):
-        run_summaries = []
-        for repeat, samples in sorted(repeats.items()):
-            run_summaries.append({
-                "run_index": repeat, "frames": len(samples),
-                "median_ms": {name: median([_measurement(row, name) for row in samples])
-                              for name in TIMING_COLUMNS},
-            })
-        entry = {
-            "shadows": shadows, "visibility": visibility, "light_count": lights,
-            "runs": run_summaries,
-            "median_ms": {name: median([run["median_ms"][name] for run in run_summaries])
-                          for name in TIMING_COLUMNS},
-            "p95_ms": {name: p95([_measurement(row, name) for samples in repeats.values()
-                                   for row in samples]) for name in TIMING_COLUMNS},
-        }
-        configurations.append(entry)
-        lookup[(shadows, visibility, lights)] = entry
-
-    candidates = []
-    evaluated = []
-    for entry in configurations:
-        if entry["light_count"] not in (32, 64, 128):
-            continue
-        baseline = lookup.get((entry["shadows"], entry["visibility"], 0))
-        if baseline is None:
-            raise ValueError("Forward+ gate requires a zero-light baseline for each mode/shadow setting")
-        zero_gpu = baseline["median_ms"]["gpu_ms"]
-        if zero_gpu <= 0:
-            raise ValueError("Forward+ gate requires positive zero-light GPU frame timing")
-        overhead = (entry["median_ms"]["gpu_main_raster_ms"] -
-                    baseline["median_ms"]["gpu_main_raster_ms"])
-        result = {"shadows": entry["shadows"], "visibility": entry["visibility"],
-                  "light_count": entry["light_count"], "overhead_ms": overhead,
-                  "zero_light_gpu_ms": zero_gpu,
-                  "overhead_percent_of_zero_gpu": 100 * overhead / zero_gpu,
-                  "absolute_threshold_reached": overhead >= 1.0,
-                  "relative_threshold_reached": overhead >= .15 * zero_gpu}
-        evaluated.append(result)
-        if result["absolute_threshold_reached"] or result["relative_threshold_reached"]:
-            candidates.append(result)
-    return {"configurations": configurations,
-            "forward_plus_gate": {"triggered": bool(candidates), "candidates": candidates,
-                                  "evaluated": evaluated,
-                                  "basis": "median of three independent run medians; same-mode/shadow zero-light GPU baseline"}}
-
-
-def _read_run_csv(path: Path, run: dict, commit: str) -> tuple[list[str], list[dict]]:
-    with path.open(newline="", encoding="utf-8") as stream:
-        reader = csv.DictReader(stream)
-        columns = reader.fieldnames or []
-        missing = sorted(set(REQUIRED_COLUMNS) - set(columns))
-        if missing:
-            raise ValueError(f"{path}: missing CSV column(s): {', '.join(missing)}")
-        rows = list(reader)
-    if len(rows) != MEASURED_FRAMES:
-        raise ValueError(f"{path}: expected {MEASURED_FRAMES} measured frames, got {len(rows)}")
-    frames = set()
-    for row in rows:
-        expected = {"light_count": str(run["light_count"]), "shadows": run["shadows"],
-                    "visibility": run["visibility"], "run_index": str(run["repeat"]),
-                    "commit": commit, "width": str(WIDTH), "height": str(HEIGHT)}
-        for name, value in expected.items():
-            if row[name] != value:
-                raise ValueError(f"{path}: {name} mismatch: expected {value}, got {row[name]}")
-        if row["effective_visibility"] != run["visibility"]:
-            raise ValueError(f"{path}: effective_visibility fell back from {run['visibility']}")
-        if row["submitted_local_lights"] != str(run["light_count"]) or row["omitted_local_lights"] != "0":
-            raise ValueError(f"{path}: submitted_local_lights or omitted_local_lights disagrees with the workload")
-        try:
-            frame = int(row["frame"])
-            errors = int(row["validation_errors"])
-        except ValueError as error:
-            raise ValueError(f"{path}: invalid frame or validation error count") from error
-        if frame in frames or errors != 0:
-            raise ValueError(f"{path}: duplicate frame or Vulkan validation error")
-        frames.add(frame)
-        if not row["device"] or not row["driver"] or not row["lighting_path"]:
-            raise ValueError(f"{path}: device, driver and effective lighting path are required")
-        for name in TIMING_COLUMNS:
-            _measurement(row, name)
-    return columns, rows
-
-
-def _git_revision() -> str:
-    root = Path(__file__).resolve().parents[1]
-    return subprocess.check_output(["git", "-C", str(root), "rev-parse", "HEAD"],
-                                   text=True).strip()
-
-
-def sweep(executable: Path, output: Path, shadows: str, commit: str,
-          validation: str = "off", driver: str | None = None) -> dict:
-    if not executable.is_file():
-        raise ValueError(f"Benchmark executable does not exist: {executable}")
-    if driver is None or not driver.strip() or driver.strip().lower() == "unknown":
-        raise ValueError("A measured sweep requires an explicit --driver identity")
-    if output.exists() and any(output.iterdir()):
-        raise ValueError(f"Output directory must be new or empty: {output}")
-    raw = output / "raw"
-    raw.mkdir(parents=True)
-    all_rows = []
-    columns = None
-    runs = build_runs(shadows)
-    command_prefix = [sys.executable, str(executable)] if executable.suffix.lower() == ".py" else [str(executable)]
-    for run in runs:
-        filename = (f"shadows-{run['shadows']}_{run['visibility']}_"
-                    f"lights-{run['light_count']:03d}_run-{run['repeat']}.csv")
-        target = raw / filename
-        command = command_prefix + [
-            "--lights", str(run["light_count"]), "--shadows", run["shadows"],
-            "--visibility", run["visibility"], "--csv", str(target),
-            "--run-index", str(run["repeat"]), "--commit", commit,
-            "--validation", validation, "--width", str(WIDTH), "--height", str(HEIGHT),
-            "--warmup", str(WARMUP_FRAMES), "--frames", str(MEASURED_FRAMES),
-        ]
-        if driver is not None:
-            command += ["--driver", driver]
-        result = subprocess.run(command, capture_output=True, text=True, encoding="utf-8",
-                                errors="replace", timeout=180)
-        if result.returncode != 0:
-            raise RuntimeError(f"Benchmark failed for {filename}: {result.stderr[-2000:]}")
-        run_columns, samples = _read_run_csv(target, run, commit)
-        if columns is None:
-            columns = run_columns
-        elif columns != run_columns:
-            raise ValueError(f"{target}: CSV schema differs from other runs")
-        all_rows.extend({**row, "source_csv": filename} for row in samples)
-
-    merged = output / "merged.csv"
-    with merged.open("w", newline="", encoding="utf-8") as stream:
-        writer = csv.DictWriter(stream, fieldnames=[*(columns or []), "source_csv"])
-        writer.writeheader()
-        writer.writerows(all_rows)
-    summary = {"format": "faset.p3-lighting-benchmark", "version": 1,
-               "commit": commit, "warmup_frames_per_run": WARMUP_FRAMES,
-               "measured_frames_per_run": MEASURED_FRAMES, "width": WIDTH, "height": HEIGHT,
-               "validation": validation, "driver": driver,
-               "runs_completed": len(runs), "rows": len(all_rows),
-               **summarize_rows(all_rows)}
-    (output / "summary.json").write_text(json.dumps(summary, indent=2) + "\n",
-                                          encoding="utf-8")
-    return summary
-
-
-def main() -> int:
-    parser = argparse.ArgumentParser(description=__doc__)
-    mode = parser.add_mutually_exclusive_group(required=True)
-    mode.add_argument("--list-runs", action="store_true", help="Print the deterministic sweep matrix as JSON")
-    mode.add_argument("--sweep", action="store_true", help="Run every configuration and retain raw CSV")
-    parser.add_argument("--shadows", choices=("off", "on", "both"), default="both")
-    parser.add_argument("--executable", type=Path, help="Built C++ benchmark executable")
-    parser.add_argument("--output", type=Path, help="New or empty evidence directory")
-    parser.add_argument("--commit", help="Source revision; defaults to this checkout's HEAD")
-    parser.add_argument("--driver", help="Required driver identity for a measured sweep")
-    parser.add_argument("--validation", choices=("on", "off"), default="off")
-    args = parser.parse_args()
-    if args.list_runs:
-        print(json.dumps({"format": "faset.p3-lighting-run-matrix", "version": 1,
-                          "runs": build_runs(args.shadows)}, indent=2))
-        return 0
-    if args.executable is None or args.output is None:
-        parser.error("--sweep requires --executable and --output")
-    try:
-        summary = sweep(args.executable.resolve(), args.output.resolve(), args.shadows,
-                        args.commit or _git_revision(), args.validation, args.driver)
-    except (OSError, ValueError, RuntimeError) as error:
-        print(f"P3 lighting benchmark failed: {error}", file=sys.stderr)
-        return 1
-    print(json.dumps({"summary": str(args.output.resolve() / "summary.json"),
-                      "runs_completed": summary["runs_completed"],
-                      "forward_plus_threshold_reached": summary["forward_plus_gate"]["triggered"]}))
-    return 0
-
-
-if __name__ == "__main__":
-    raise SystemExit(main())

tools/project_templates/lua-main.lua

@@ -0,0 +1,22 @@
+-- Faset starter gameplay. Edit this file and use Refresh Lua or development reload;
+-- the native C++ engine does not need to recompile for a Lua-only edit.
+local Player = faset.behavior {
+    id = "starter.player",
+    version = 1,
+    name = "Player",
+    fields = {
+        speed = { name = "Move speed", type = "number", default = 4, min = 0 },
+        jump_speed = { name = "Jump speed", type = "number", default = 5, min = 0 }
+    }
+}
+
+function Player:fixed_update(delta)
+    local velocity = self.entity:velocity()
+    velocity.x = faset.input().horizontal * self.fields.speed
+    if faset.input().jump_pressed and self.entity:is_grounded() then
+        velocity.y = self.fields.jump_speed
+    end
+    self.entity:set_velocity(velocity)
+end
+
+return Player