Coloured matte surfaces

This image adds a surface physics model to the five white spheres. The surface itself is a perfect matte, and would normally be used as a single layer in a more realistic texture. This type of surface is called Lambertian and nearly exists in the real world.

The colour that we see on any part of the sphere is based on three things:

• The colour of the light hitting it.
• The colour of the sphere itself.
• How close to 'directly below' the part of the surface is to the light.

Basically the first two contribute to the colour, and the last to how much of that colour there should be.

The code is at Scenes/early/coloured-matte-surfaces.cpp.

• 1920 × 1080
• 462 × 260
• 128 × 72