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
- UBO expanded from 64 to 128 bytes: vp(64) + lightPos(16) + lightColor(16)
- Vertex shader: passes point light UBO data through
- Fragment shader: refactored calcLight() function, shared by directional + point
- Point light: Unity-style attenuation pow(1 - dist/range, 2)
- Directional light reduced intensity (0.4) to balance with point light
- Point light: position (0,8,0), warm color (1,0.9,0.7), intensity 15, range 25
- Renderer: reads Light component from ECS, packs into UBO with Marshal.StructureToPtr
- Scene: MainLight entity with Light.Point at (0,8,0)
- 0 C# struct changes — pure UBO layout + shader upgrade
emil28092005