Crash: VraySamplerInfo Occlusion + changing topology

[RotemS]

Symptom: 3dsmax will crash or hang when rendering an object with changing topology (in some, but not all cases), when a VraySamplerInfo element is active, with mode set to forward/backward occlusion.

Tested on: 3.20.02, 3.30.04, 3.35.01 Nightly 26667 with 3dsmax 2014.

Vraylog.txt error: UNHANDLED EXCEPTION: Rendering region (144,192)-(192,240)
Last marker is at ./src/globillummap.cpp, line 1855: GlobalIllumMap::buildLightMap() {1}

Attachments: repro scene (render frame 0), vraylog.

If you can offer any temporary workaround (even one which requires me to recompile VraySamplerInfo) it would help us greatly.

To be clear, I have no expectation that the data will be accurate (due to the changing topology), only to avoid the crash.

Thank you.

Update:
To the best of my ability to check, the exception is thrown inside DefaultVRayShadeInstance::getBasePt called from Line 84 of vraysamplerinfotex.cpp:

Vector pt=si->getBasePt(rc, (which==timeMoment_frameEnd)? DefaultVRayShadeInstance::baseTime_frameEnd : DefaultVRayShadeInstance::baseTime_frameStart);

[tashko.zashev]

Thank you for attaching the files for this issue.
It is reproducible in my render tests here so I'm going to forward it to our developers for a further investigation.
Meanwhile you can bake this animation into a vrmesh/proxy file before rendering it.

[RotemS]

Thank you.

If you discover some render setting which prevents this crash or manage to get this fix into a coming nightly please let me know.

[RotemS]

Hi. Do you have any news regarding this bug?

[tashko.zashev]

Hi. Do you have any news regarding this bug?

Unfortunately not yet. We will notify you when the fix is part of the nightly builds.

[stefan_b]

Hi Rotems,

The problem with changing topology is now fixed in the nightly builds. Could you check and see if there is any other issue with that? Thanks!

[RotemS]

Hi Stefan,

I'm afraid it's still crashing in nightly #26781.

EDIT: Actually, hang on. That might be my bad. Will update in a bit.

[RotemS]

Yes, it is working fine now, at least for the VraySamplerInfo element.
In my own custom element, still crashing. Is the version of vraysamplerinfotex.cpp updated in the latest nightly? If so I'll check what adaptations need to be made.

[stefan_b]

Hi RotemS,

The actual code change is not in vraysamplerinfotex.cpp - it concerns getBasePt method. Is your own custom element based on vraysamplerinfotex?

[RotemS]

Yes, specifically the forward/backward occlusion aspects of it.
I'll investigate if I find any problem before wasting your time on it. I'll update this thread if I can't get it to work. Thank you.

[RotemS]

Ok, got it! The difference is not in code, but with the settings I'm using. With the same settings, the VraySamplerInfo element crashes as well.

To reproduce in the test scene attached to the first post in this thread, use an interval center of 0.0 and set geometry samples to 3, and render frame 0.

[RotemS]

Were you able to recreate this? I'm really hoping it could get fixed for 3.40 as we'll probably be upgrading our pipeline to use it. It's still crashing in today's nightly.

[vlado]

There was one crash that was fixed, but there is also another one that isn't yet. One of the guys is still looking into it.

Best regards,
Vlado

[RotemS]

Thanks for the update.

[stefan_b]

Hi RotemS,

This problem is now fixed in the nightlies. However there are still some issues with particle flow and VRaySamplerInfo that we are working on.