Error Exception module=1, what does this mean

[djx]

The exact error message is
Error: There was a fatal error rendering the scene.
Error: Exception [module=1] : Rendering region (640,320)-(704,384)

It goes away if I turn off GI (bruteforce + lightcache), or if I hide a particular object. If you can tell me what the "module=1" refers to it might help me track down the problem.

thanks
David

[alainfx]

What version of VRay are you using ?

With the Nightly Build 14024 (Maya2011 64 bit) I had a lot of "Exceptions" when processing "Render Region".
After installing the latest Nightly Build (14259), the problem never came back.

Cheers.

[aweidenhammer]

Having the same error here. We found it was a particular particle system causing it. We rebuilt the particles, unfortunately.

[vlado]

If you keep the scenes around, it might be useful to send them to us at vraymaya@chaosgroup.com for investigation.

Best regards,
Vlado

[djx]

Thanks all for the feedback. I'll try the latest build on Monday. Currently I'm using the one from last Monday (I dont have the build number with me). The first error is when I'm using the vfb, where I'm doing a full frame, so I guess in this case "region" refers to the tile being rendered. The problem surface is being deformed by a wrap. It does not fail on every frame, but it is consistent on the frames where it does. If it persists after updating the build, I'll send you a scene vlado.

[djx]

The problem turned out to be the diffuse result in the vray material. I am using self illumination with an opacity map, and diffuse=0.
The solution was to make diffuse NOT zero. I used diffuse color = white and diffuse amount = 0.000001

strange

[vlado]

Yes, it is strange... a scene would still be welcome

Best regards,
Vlado

[djx]

I thought I'd found a workaround for this problem, but it only worked on that particular scene. The same error seems to pop up in other situations. It is difficult to work out what is the cause because it seems to depend on several things. Change one and it goes away. The worst part is that it seems to depend on camera and object alignment too, so may just affect 1 or 2 frames in a sequence. Moving an object slightly fixes it.
The best I can work out is that there is something involving opacity mapping vray materials and the extraTexture renderElement.

Vlado, can I email you a file and if so, to where?

I tried to attach a scene file, and some fileTextures. But it is approx 500k

If you render frame 190 in the vfb it should work and render a small grey patch. If you then click the teapot and select a region around the grey patch and render again, then it may fail. If it does succeed, try a larger region. For me, the region needs to be approx 1/4 the size of the frame.
This is not actually how I've been experiencing the error, which has been occurring during batch renders, but it is a way to reproduce it on demand.