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LuxCoreRender / BlendLuxCore

Blender Integration for LuxCore
GNU General Public License v3.0
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Specular bounce through fog doesn't render - could we have support for this please? #921

Closed Sarah-C closed 2 months ago

Sarah-C commented 3 months ago

I've just installed https://github.com/LuxCoreRender/BlendLuxCore/releases/tag/latest

I've used metal as my water to ensure I get a reflection - but the bounced indirect light rays don't bounce off it!

(Without the metal ocean, the bounce off the diffuse ground works perfectly, illuminating the internals naturally with bloom from the fog. It's just this specular second bounce travelling through fog that isn't drawn)

Bidirectional - Metropolis - 20 bounces...

image

I've got a world volume so the exterior volume for the metal "ocean" isn't required.

Test scene:
https://untamed.zone/demoLUX.blend

Teesingly - changing the renderer to Pathtracing - Sobol, captures the bounce off the metal! (Below) We can see the caustics off the water making bars too!

So the material's sure correct, but it appears Lux Core can't do this particular setup?

So the limit of Lux Core would be rendering a search light beam bouncing off the ocean at night in fog? I've seen fog specular between lenses so transparent objects handle this fine.

image

Is there some way I can tweak my materials or setup for the bidirectional metropolis render? Or is this an ok feature request?

Also - I have no idea what to call this type of light? "Diffuse illumination from particles" ? "Specular diffraction from particles" ?

Sarah-C commented 2 months ago

Other scenes render ok - this must be an issue with the scene!