Operating system: Windows 10 x64
Graphics card: NVidia Quadro RTX 3000 and NVidia RTX 3080
Blender Version: 3.4.1
Issue: it looks like current caustics only supports one object, which makes it impossible to properly render any scene with liquids/bottles of liquid etc.
Exact steps for others to reproduce the error:
- Create a refractive object like glass.
- Use Glass BSDF or Principled BSDF on it with transmission/roughness maxed out.
- Put another object (liquid) inside of it, use similar Glass/Principled BSDF with transmission on it.
- Put ground plane with default Principled BSDF
- Enable "cast caustics" for both objects.
- Enable "receive caustics" on plane.
- Add light source and enable "shadow caustics" for it.
- Enable "reflective and refractive caustics" in render settings.
- Separate "liquid" and "glass" objects to test them separately from each other.
- Check results - Caustic shadow shows as a dark opaque shadow for liquid inside glass. Caustic shadow renders properly for separated objects on their own.
Added another image where I removed glossy filtering and clamping, set light bounces to 64, and increased samples to 1000000. Same result.