P2b: offline WAV render of the arrangement

README.md

@@ -2,7 +2,7 @@
 
 Sound is terrain. A sampling instrument where material is cut in a quarry, laid as stones in a nave, and played by a hand or an agent through the same verbs.
 
-This repository is **P2 in progress**: the engine, the wire, the descent, the quarry, a persistent project, recording, manual faces, undo across restarts, a native host — and an **8-bar arrangement of four sections**. A found or recorded sound is cut into sixteen faces, laid on a vein, arranged across A–D, and heard as an eight-bar loop; the render and the agent are the remaining P2 slices. The visual demo in [`reference/demo`](reference/demo) remains a design reference, not the codebase. The roadmap is in [`docs/PLAN.md`](docs/PLAN.md).
+This repository is **P2 in progress**: the engine, the wire, the descent, the quarry, a persistent project, recording, manual faces, undo across restarts, a native host, an **8-bar arrangement of four sections**, and an **offline WAV render**. A found or recorded sound is cut into sixteen faces, laid on a vein, arranged across A–D, heard as an eight-bar loop and rendered to a 16.5-second WAV; the agent is the remaining P2 slice. The visual demo in [`reference/demo`](reference/demo) remains a design reference, not the codebase. The roadmap is in [`docs/PLAN.md`](docs/PLAN.md).
 
 ![The quarry](preview-p1-quarry.png)
 
@@ -18,6 +18,8 @@ This repository is **P2 in progress**: the engine, the wire, the descent, the qu
 
 ![P2 · eight bars, four sections](preview-p2-arrangement.png)
 
+![P2 · an offline render](preview-p2-render.png)
+
 ## What is real
 
 - **Rust engine.** `cpal` output at 48 kHz, five veins, a sixteen-step phrase, a fixed voice pool, per-vein levels and gains, a bar clock. Procedural voices for empty pattern rows; real sample voices for rows with a face. No Web Audio.
@@ -32,6 +34,7 @@ This repository is **P2 in progress**: the engine, the wire, the descent, the qu
 - **Surface.** A Svelte 5 descent whose terrain, eye, city, road, stones and playhead react to the five levels and the master; a real wire log; engine facts; cilia; a master signal trace; vein gains; transport; keyboard.
 - **Native host.** The Tauri app starts the same host inside its own process: engine, session, SQLite project, assets and loopback wire. The built window is self-contained; the browser path uses the standalone daemon. One process owns `127.0.0.1:4317` at a time.
 - **Arrangement.** Four 2-bar sections (A–D) make an 8-bar loop. The engine plays the sections in order; the descent draws all eight bars with section seams and letters; the quarry edits the active section, selects, copies and clears. The sections, the active section and their edits are persisted and undoable; the pattern rows and faces stay per section.
+- **Render.** The `render` button (or the `render` command) renders the full 8-bar arrangement offline with the same voices, gains, sample faces and master as the live engine, then writes a 32-bit float stereo WAV to `<project>/renders/`. The `rendered` event carries the path and duration; no device is opened for the render.
 - **Verification.** Rust unit tests, a live wire test, a material import test, a browser quarry test and the P0 regression smoke, plus `svelte-check` and a production build.
 
 The Tauri 2 app is **built and running with its own engine**: the native window loads the embedded surface and the host starts the engine, session, project and wire in the app process. It is built with Tauri 2.12.5 / CLI 2.12.4 against WebKitGTK 2.54.2, GTK 3.24.52 and dbus 1.16.2. The binary is `app/src-tauri/target/release/zhila-app` (14 MB); installers are a later step.
@@ -105,6 +108,8 @@ npm --prefix ui run project-smoke     # daemon + Vite: project, undo, import, sc
 npm --prefix ui run record-smoke      # daemon + Vite: fake microphone take, faces, seal
 npm --prefix ui run faces-smoke       # daemon + Vite: drag a seam, trim, save, screenshot
 npm --prefix ui run arrangement-smoke # daemon + Vite: sections, edit B, 8-bar descent
+node scripts/render-smoke.mjs        # daemon running: render, parse the WAV
+npm --prefix ui run render-ui-smoke  # daemon + Vite: render button, wire, screenshot
 cd app && ./node_modules/.bin/tauri build --no-bundle   # native app with the embedded host
 npm --prefix ui run restored-smoke    # after restarting the daemon on the saved project
 ```
@@ -114,7 +119,8 @@ npm --prefix ui run restored-smoke    # after restarting the daemon on the saved
 ## P2 limits (in progress, not hidden)
 
 - The arrangement is exactly four 2-bar sections; no section length, reorder, insert or per-section mute yet.
-- Render and the agent are the next P2 slices; they are not in this commit.
+- Render is 48 kHz stereo 32-bit float with a 1.5 s tail; no stems, normalisation or per-section export.
+- The agent is the remaining P2 slice.
 
 ## P1 limits (kept honest)
 
@@ -129,4 +135,4 @@ npm --prefix ui run restored-smoke    # after restarting the daemon on the saved
 - No agent/MCP in this phase.
 - The Tauri shell now builds and runs; the engine is still the separate daemon (embedding is next).
 
-P2 is the arrangement, the offline WAV render and the in-app agent. P2a (the arrangement) is in this tree; P2b and P2c follow. The plan is in [`docs/PLAN.md`](docs/PLAN.md); the phase notes are in [`docs/P2.md`](docs/P2.md). The plan is in [`docs/PLAN.md`](docs/PLAN.md); the phase notes are in [`docs/P1.md`](docs/P1.md).
+P2 is the arrangement, the offline WAV render and the in-app agent. P2a (the arrangement) and P2b (the render) are in this tree; P2c follows. The plan is in [`docs/PLAN.md`](docs/PLAN.md); the phase notes are in [`docs/P2.md`](docs/P2.md). The plan is in [`docs/PLAN.md`](docs/PLAN.md); the phase notes are in [`docs/P1.md`](docs/P1.md).