Hi there,
My session permanently crashes when trying to render displacement in karma CPU/XPU with the Principal or MaterialX shader.
Im trying to add materials to an RBD sim, but it also happens with other geometry, but not with any geometry.
I can render a Grid with displacement with no issues at all. It only seems to crash with more complex geometry. Therefore, I'm quite certain that the issue comes from my geometry. Even though Mantra for example, renders everything with displacement correctly and without crashing.
I tested this in H19, H19.5.303 and H19.5.353.
I contact SideFX support and sent them a hip file, but they were not able to reproduce the issue. I was able to reproduce it on 2 machines very consistently.
Here is a short video showing the behavior [streamable.com]. In the video, the shader had displacement. When I disconnect it, everything renders totally fine.
Sometimes it does render the displacement, but if I then change a parameter or move the camera, it usually crashes.

Here is my MaterialX material with displacement [imgur.com]

Here is a hip file, 1 frame from a sim as a USD and a displacement map [we.tl] if you would like to try it out yourself. I know it has to do with the geometry, but I have no clue what the issue might be.

Thanks!

I tried your zip package on Linux, and it works, renders fine.

The first thing I would do if I found myself in your situation: Eliminate viewport issues and try to render via husk and a high verbosity level, so you can see a better logfile of what's actually going on.

protozoan
I tried your zip package on Linux, and it works, renders fine.

The first thing I would do if I found myself in your situation: Eliminate viewport issues and try to render via husk and a high verbosity level, so you can see a better logfile of what's actually going on.

Thanks for your help, Martin. While I wasn't able to render with husk, I did get some info from the console. I get this error message twice before the render crashes:
[17:22:37] Detected edges with more than 2 incident faces. [17:22:41] Detected edges with more than 2 incident faces. Not sure what this means. Do you?

I also rendered with high verbosity, but I don't know what I'm looking for in the log. I attached it to this message.

Just to reiterate, without displacement, it renders just fine. In the viewport and with husk.

Thanks!

That's (potentially) ugly but not condemning.

I noticed from your log that you are using a very new ryzen. I tested this again, against an old Threadripper (closest thing I have), but it also renders fine.

You've definitely entered the Twilight Zone.