Refractive Caustics (Blender 3.2+)

A geometry nodes refractive caustics generator for Blender 3.2+

Main Features:

• Generate appealing caustics patterns in real time
• Dispersion with variable number of colour bands
• Volumetric light rays (EEVEE only)
• Many other parameters including adjustable IOR, light direction, and intensity.

Included:

• Demo .blend file with geometry nodes setup, materials, and multiple different preset input meshes to try

Note:

• Generated caustics rely on the topology of the input mesh. Higher subdivision, grid-like meshes will produce higher quality caustics.
• To avoid artifacts when rendering with Cycles, it may be necessary to increase transparent light bounces (Render Properties > Light Paths > Max Bounces > Transparent).
• Volumetric light rays are not supported with Cycles. Disconnect this output from the node group when rendering with Cycles.

Please credit me if you use this setup in your work. Enjoy!

Version History:

v1.1.1

• Fix: Incorrect refraction caused by un-normalised light direction

v1.1

• New dispersion method - greatly reduces tinting of volumetric light rays when using many colour bands. Inspired by CGVertex: https://www.youtube.com/watch?v=lEPZ1IUkoB4.

  

• Adjusted default displacement strength to a more reasonable range

v1.0

• Released