shadowcatcher gpu problem

V-Ray V-Ray GPU Issues
1

simpel scene - a plane with shadowcatcher, chamferbox, vray planelight, hdri.
Rt gpu on the right.
Works fine if I remove shadowcatcher.
Will send file

.jpg.jpg
.jpg.jpg1824Ă—610 119 KB

2

Could you please attach the file?

3

sorry had a busy schedule…
I have send it to support

4

Thank you for sharing the scene. The issue is logged for investigation. It’s caused by the LC, if you disable Use for glossy rays or Store direct light option it will fix it.
I’ll let you know when we have any update.

5

Thanks for the quick solution

6

Hi, is shadowcatcher working properly in official vray next release? Shadows affect alpha is not working in beta 3

7

There are no additional fixes for the shadow catcher in the official release compared to beta 3.
We have in the todo list to improve it.

Bets,
Blago.

8

When you render inside Modo, the GPU renderer is in “interactive” mode, so the light cache is not used.
I guess this is the reason the “inside Modo” render is working correctly.

Greetings,
Vladimir Nedev

9

Cpu and gpu differs a lot with shadowcatcher.
here is a simple scene. A box, plane(with shadowcatcher), 1 vray light and green background.

Green color is not the same and alpha on Gpu is all white.

simpelsceneCPU.jpg
simpelsceneCPU.jpg640Ă—360 46.9 KB

simpelsceneGPU_alpha.jpg
simpelsceneGPU_alpha.jpg640Ă—360 1.63 KB

simpelsceneCPU_alpha.jpg
simpelsceneCPU_alpha.jpg640Ă—360 63.2 KB

simpelsceneGPU.jpg
simpelsceneGPU.jpg640Ă—360 80.2 KB

10

Yes, they use completely different algorithms. The white alpha on the GPU is strange though. Can you post that scene, even though it is very simple? The alpha looks fine in my simple tests.

Best regards,
Vlado