Caustic Pool Project File for Blender 3.1

This Blender project file uses 100% Geometry Nodes to create a fake caustic effect.

Inspired by Evan Wallace, it works best in Eevee as Cycles tries to merge the geometry and screws things up.

You can swap the pool for any other geometry in Edit Mode.

The amount of subdivisions control the caustic quality, but also the brightness. The light shader has a Divide node which controls the caustic brightness.

Geometry Nodes control the IOR values of the inside and outside materials, plus chromatic dispersion and colour is adjustable.

The pool is animated and the water is generated using a noise texture. The height and complexity of the water can be adjusted using Geometry Nodes.

Please note this isn't physically accurate, since it assumes the pool would receive 100% light. If the pool is swapped for other geometry it's even less accurate, since the light won't bend back to normal as it exits the geometry.

Requires at least Blender 3.1 due to the Face Area node.