V-Ray RT GPU vs CPU vs Production.

[eyepiz]

Hello,

I have a small rendering scene built with all GPU sported features, however, the results are not good compared to CPU or Production.

The scene is simple, floor plane and a dome light with an HDRI.

The obvious...the floor plane is reflecting the HDRI from the dome in the far back, The material has a Fresnel IOR of 3.0 with CPU and production the reflections disappear with distance, so there seem to problem with GPU and Fresnel.

The back of the chair has a color correction, looks just odd in GPU.

The seat has a bump map and a falloff, the bump is a map not a procedural map. the bump is not as pronounced as in CPU and production.

I normally use a mtlwarraper on a vray plane for Matte shadow and reflection to omit the background altogether...but RT GPU does not support both those feature.

any ideas on what the issues may be?

Thanks!

[Svetlozar Draganov]

Hello,

Would it be possible to send us this scene for investigation ?

[eyepiz]

Hello,

Would it be possible to send us this scene for investigation ?

Scene sent...Thanks!

[Svetlozar Draganov]

Thanks for the scene.

I managed to find out the first issue with the ground reflection differences between CPU and GPU. It seams that this issue persist only if opacity and reflection are used simultaneously.
I am going to report this into our database and will inform you when we have some progress.

The back of the chair use opacity texture with high-frequency details which are not sampled very well by the GPU so far - this is also reported.

Matte Objects and Displacement are still not supported - we have them for a long time into our system waiting to be developed.