abstrax wrote:milo_dude wrote:abstrax wrote:
I can confirm an issue in the ray-tracing kernels, but I don't know what exactly is causing the problem and how to solve it. I hope to find a solution with the next release.
EDIT: This scene creates some insane geometry and I can reproduce the kernel failure with only the cloner object at the bottom of the object tree under "Body". I'm not sure what the point of it is, but it creates 500 flat cube objects that are all intersecting each other in a tight cylindrical volume. Rendering shouldn't fail of course, but maybe this can be modeled a bit more "render friendly".
Maybe you right about insane geometry, but the problem is in the "HUD" childe objects wich is sweep.
If i shut it off everything fine.
Is it possible that the trouble is in illustrator spline import?
i'm so confused that it's worked in 3.05
I had to restructure things a lot to make CUDA 8 builds as fast as CUDA 7.5 builds, maybe I broke something along the way. Will try to figure it out today.
Thanks a lot for this scene. It allowed me to find a bug I have been hunting for more than 3 months. The cause of this issue has been there since we introduced instances in version 1. In the past it hasn't been an issue, but now with the increase of scene sizes made possible by modern GPUs with lots of VRAM, it occurs more often. Unfortunately those extremely large scenes made the problem impossible to find (for me at least)... until your scene came along, which is quite simple, but causes the geometry compilation to generate a degenerated acceleration structure.
The reason why it didn't occur with 3.05.3 is probably because CUDA 7.5 is arranging working memory differently than CUDA 8.0, hiding the issue. This is your scene rendered with a quick fix, which unfortunately has quite a large performance hit (about 10% in the ATV scene - compared to 3.06 test 4):
I will try to find a solution that isn't as bad performance-wise, but let's see...
In theory there is no difference between theory and practice. In practice there is. - Yogi Berra