Caustics is not visible behind glass material

[yiusay]

Hi

I am new to LuxCoreRenderer and am trying to render caustics in pool by following this tutorial.
viewtopic.php?f=13&t=1634&p=18785

This is my current rendered image.
https://drive.google.com/file/d/1uZtfq9 ... sp=sharing

The caustics is rendered on the pool floor but is not visible if it is behind the objects with glass material. According to the tutorial, I believe caustics under water can be handled by LuxCoreRenderer. Can someone point out what the problem is? I appreciate any feedback to solve this problem.

Here is the blender file.
https://drive.google.com/file/d/1XCLMcS ... sp=sharing

I am also wondering if LuxCoreRenderer can render caustics behind glass materials in general.

Thank you
Yusuke

[B.Y.O.B.]

The blue surface on the pool floor has a disney material with roughness = 0. This is more specular than the PhotonGI glossiness threshold, so the surface will not store photons.
After setting the roughness to a higher value like 0.4, photons can be stored on it.

[yiusay]

I appreciate your quick feedback!
It works now. The result looks very pretty

https://drive.google.com/file/d/1VDgqEn ... sp=sharing