GPU Bug - Matte objects shadow is 100% solid

V-Ray V-Ray GPU V-Ray GPU :: Issues
1

Hi Guys

With GPU, selecting a plane and using the toolbar’s Matte Object button, results on shadows that are 100% white (solid) in GPU rendering. No matter if we use the VRayProperties or the MaterialWrapper, the result is the same.

With CPU on the other hand, the shadow correctly has a less “solid” look.

Both CPU and GPU produces the correct shape, its just the solidness of the shadow that is the issue on GPU

Easily reproducible with GPU. Make a plane, stick a box on it. Add vraysun and cam. Select plane and make matte. Render, then view alpha channel.

2

On GPU, there’s no GI on mattes (it’s written in the docs). You can render the GI separately and apply in post.

3

Can you share the comp math for that please?

4

I actually retract my words - not sure if you can get matching results by doing simply overlaying a regular GI element from the RGB. You better render out the matte separately with CPU instead (since the GI is included in the alpha there).

5

well that’s no good

A feature request would then be to get it working correctly with GPU

6

@Morne This is near the top of our priority list, we will take a look at this soon

Best,
Muhammed

7

Thanks, good to know