Root cause: GLSL std140 layout adds padding after mat4 for vec4 fields,
causing light data to be read at wrong offsets → NaN/artifacts.
Fix:
- UBO back to 64 bytes (mat4 vp only)
- Light data (pos + color, 32 bytes) sent via push constants at offset 64
- Two push constant ranges: Vertex (0-64, model) + Fragment (64-96, light)
- Both vertex and fragment shaders read from same push_constant block
- PBR shader fully restored with Cook-Torrance BRDF
- Dynamic point light follows physics ball
Root cause: descriptor set layout binding had stageFlags=Vertex only.
Fragment shader needs pointLightPos/pointLightColor from UBO but couldn't
access it. Changed to Vertex|Fragment.
- Push constant changed from float angle (4B) to mat4 model (64B)
- Two draw calls with different model matrices (x=-1.5 and x=+1.5)
- Both cubes rotate around Y axis at 0.2 rad/s
- 0 validation errors
- Load Content/cube.obj via ObjLoader (36 vertices, 36 indices)
- Depth buffer re-enabled: depth test + write, CompareOp=Less
- Depth image transition + depth attachment in rendering info
- Push constant angle=0 (no rotation)
- Camera at z=-2, perspective FOV 45°
- UINT32 index type (fixed in previous commit)
- Face normals computed by ObjLoader (no vn in cube.obj)
- 0 validation errors
- vkCmdBindIndexBuffer indexType changed from 0 (UINT16) to 1 (UINT32)
to match uint[] index data — this was causing black screen
- Removed depth stencil state, depth attachment format, and depth
rendering attachment from pipeline/renderer (depth buffer still
created in swapchain but unused)
1. VkColorComponentFlags: wrong bit values (0x10-0x80 instead of 0x01-0x08)
→ colorWriteMask was 0xF0 instead of 0x0F → no color channels written
2. VkClearValue: was Sequential layout instead of Explicit (union)
→ depthStencil clear value written at wrong offset → depth buffer
cleared to 0.0 instead of 1.0 → all fragments failed depth test
3. Vulkan clip space correction in vertex shader:
gl_Position.y = -gl_Position.y (Vulkan Y-down vs OpenGL Y-up)
gl_Position.z = (gl_Position.z + gl_Position.w) * 0.5 (Z [0,1] vs [-1,1])
Also:
- PushConstantSize fixed from 128 to 144 (two mat4 + vec4)
- Dynamic viewport/scissor state added to pipeline
- Push constants use column_major (default) to match System.Numerics row-major layout
- Camera.GetProjectionMatrix reverted to pure OpenGL-style (correction in shader)
- Screenshots show actual 3D geometry (calibration cubes visible)
- 66/66 tests pass
ImGui:
- ImGui.NET 1.91.6.1 NuGet package
- VulkanImGui: font texture upload, ImGui pipeline (blending, no depth), vertex/index buffer streaming
- GLSL 450 ImGui shaders (vert: scale/translate push constants, frag: font texture sampler)
- Compiled to SPIR-V via @webgpu/glslang
- Debug overlay: FPS, camera position, entity count, light list
- 1600+ FPS with ImGui active
Screenshot:
- vkCmdCopyImageToBuffer embedded in main command buffer
- Layout transition PresentSrcKHR→TransferSrcOptimal→PresentSrcKHR
- Deferred read: staging buffer read on next frame after fence
- BMP format written directly to FileStream (row by row)
- All 16 camera tour screenshots captured (1280x720x32bpp)
All 66 tests pass.
emil28092005