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Maya 2020.3 and VRay5 hotfix 2
Hello, we are experiencing buggy behavior when rendering in GPU mode with on-demand mipmapping and textures that are using the VRayUVWRandomizer node. What we are seeing are rectangular artifacts. I will try to list some findings in the hopes that it will help narrow things down:
The artifacts look like they have random orientations, which makes sense with stochastic rotation randomization.
The artifacts change from frame to frame, including re-rendering the same frame on the same machine.
The artifacts only appear in Bucket mode, not Progressive.
The artifacts are affected by Bucket boundaries.
The artifacts are affected by anti-aliasing settings such as min samples.
The artifacts seem to be affected by bucket order, for example Spiral, Top/Bottom, etc. In initial testing of still renders we saw that initial buckets were free of artifacts, only appearing once the frame got further along. So for example, reversing the bucket order changed where the artifacts appeared.
The artifacts seemed affected by the presence of other geometry. Simple plane with UVWRandomized texture – fine. But place a cube in the middle and artifacts appear.
The artifacts are much more noticeable when switching from Adaptive lighting to Full Evaluation.
The artifacts disappear in GPU mode when switching from On-demand mipmapping to Full-Size textures.
The artifacts are not present in CPU mode.
Lots of different, wacky behaviors going on.
Video here:
https://drive.google.com/file/d/1oOz...ew?usp=sharing
File here:
https://drive.google.com/file/d/1ih3...ew?usp=sharing
As an aside, the stochastic tiling is not as nice looking in GPU mode compared to CPU. I suspect this is some kind of limitation in the GPU implementation, rather than a bug. When using rotation randomization in GPU mode, the tile borders are still straight as opposed to rotated as in CPU mode. You can see this in the above video.
Thank you.
Hello, we are experiencing buggy behavior when rendering in GPU mode with on-demand mipmapping and textures that are using the VRayUVWRandomizer node. What we are seeing are rectangular artifacts. I will try to list some findings in the hopes that it will help narrow things down:
The artifacts look like they have random orientations, which makes sense with stochastic rotation randomization.
The artifacts change from frame to frame, including re-rendering the same frame on the same machine.
The artifacts only appear in Bucket mode, not Progressive.
The artifacts are affected by Bucket boundaries.
The artifacts are affected by anti-aliasing settings such as min samples.
The artifacts seem to be affected by bucket order, for example Spiral, Top/Bottom, etc. In initial testing of still renders we saw that initial buckets were free of artifacts, only appearing once the frame got further along. So for example, reversing the bucket order changed where the artifacts appeared.
The artifacts seemed affected by the presence of other geometry. Simple plane with UVWRandomized texture – fine. But place a cube in the middle and artifacts appear.
The artifacts are much more noticeable when switching from Adaptive lighting to Full Evaluation.
The artifacts disappear in GPU mode when switching from On-demand mipmapping to Full-Size textures.
The artifacts are not present in CPU mode.
Lots of different, wacky behaviors going on.
Video here:
https://drive.google.com/file/d/1oOz...ew?usp=sharing
File here:
https://drive.google.com/file/d/1ih3...ew?usp=sharing
As an aside, the stochastic tiling is not as nice looking in GPU mode compared to CPU. I suspect this is some kind of limitation in the GPU implementation, rather than a bug. When using rotation randomization in GPU mode, the tile borders are still straight as opposed to rotated as in CPU mode. You can see this in the above video.
Thank you.
