Five spheres with coloured lights

Compared to the white sphere the internals of the ray tracer are a good deal more sophisticated by here:

• A model type that allows aggregation of geometry, and affine transformations (although only translations are used).
• A pinhole camera that has real-world focal length (50mm) and film size (35mm), but linear exposure.
• Multiple lights each with their own colour.

There is still no surface physics other than a very simple hard coded shading model — the colour on the spheres all comes from the colours of the lights.

This extra complexity, both in terms of the models and the capabilities mean that this render is about 25 times slower than the last. See the code at Scenes/early/five-spheres-coloured-lights.cpp.

• 1920 × 1080
• 462 × 260
• 128 × 72