Caustics refers to the bending and refraction of light when passing through transparent materials.
- A caustic is the envelope of light rays reflected or refracted by a curved surface or object, or the projection of that envelope of rays on another surface.
The Caustic effect produces focused light and shadow effects from a point light.
This is a glass bowl of apples, (with a pyramid procedural bump effect), and a glass cone, rendered with transparency and refraction, and with Caustic effects. (Reflection 0.90, refraction 1.15).
These scene is illuminated with a spotlight.
Note: Caustic does not currently work with the Sun for illumination. This scene was illuminated with a spotlight.
This is the same model but no Caustic effects.
Note that with the Normal setting, objects which are highly transparent do not cast appreciable shadows.