VrayEnvironmentFog - odd behavior on renderfarm

[deepblue812]

I was playing around with the example scene of the clouds made from the VrayEnvironmentFog (on Max2008/VRaySP3) from the online help. I adjusted some of the noise and animated a few of the maps and some other tinkering, nothing too crazy. It rendered fine locally (about 4 minutes per frame), so I tried sending a sequence to the our renderfarm (via Backburner).

After a bit I noticed only one machine was rendering, the others were just stalled. Trying to narrow down the problem, I just sent the scene to one machine, which would render fine. Sending to a different machine would also render fine. As long as the job was only sent to one machine it worked fine. Sending to multiple machines it would only start the render on one machine.

I made a few other quick scenes without any VrayEnvironmentFog and they would also render fine. I went back to the original cloud scene, just unticked the 'active' box on the Fog and re-sent it, and it rendered fine. (?)

It's almost like the first machine to 'get to' the scene starts rendering, but the others just endlessly sit there. just turning off the fog fixes it.


SteveJ

[vlado]

Would it be possible to get me that scene to vlado@chaosgroup.com?

Best regards,
Vlado

[deepblue812]

sent!

edit -

A bit more tinkering, and it seems to be not directly the VrayEnvironmentFog, but the animation of the noise map within it.

I went back to the original cloud1.max scene from the spot3d online help. I sent that as-is as a sequence to the renderfarm, and all the machine immediately were running at 100%.

I animated just the noise map (that's inside the VrayCompTex) from frame 0-1000, value 0->120 on X and Y, the phase from 0 -> 5

sent it again, and no go, just one machine would render (the others just run max endlessly at 12%, as though it's just loading, but even at then nothing ever renders). I tried the phase animated separately from the x/y pos and the same result.

I took the noise map out of the VrayCompTex and used it just by itself (the noise map) and tried it again, same result. As soon as I took the animated keys off the noise map, worked fine again.

Last test was taking the atmospheric gizmo out of the scene, and just putting a regular plane there. I put the same animated VrayCompTex/noise map onto it and rendered, and it also wouldn't work.

So it seems that the animated noise is mucking things up, but I'm sure I've rendered an animated noise map before just fine.

SteveJ

[deepblue812]

I've narrowed it down to something I can reproduce locally. In the attached scene the atmospheric gizmo has the animated noise on it. The first frame renders fine, but after that the 2nd and onward frames get stuck in the LC calcs forever.

However, if you replace the animated map with a static one, you can set the values to the same as they would be for whatever frame from the animated one would be and it renders fine.

so it seems to be something with the VrayEnvironmentFog + animated noise map on the Fog Density slot + LightCache + not the first frame (either with or without an atmos gizmo)

SJ

[deepblue812]

keeps getting a bit more odd. I went back to my original animated cloud scene and got it to repeat the same problem of rendering the first frame but not any frame after that. I tried all the different bounce types, and it didn't matter if it was LC, IR, BF, etc.

Then I found if I changed the timeslider range, it would render the first frame of the timeslider (ie frame 120) but if I moved the timeslider to a different frame it wouldn't render again.

or if I set the render render range, it would render the first frame of that, but tend to not render the next frame.

Then after fidling with those 2 things, it would all of a sudden work for all the frames. then break again.

Now it seems that as long as the machine is allowed to at least start rendering frame 0 (ie the first keyframe of the animation) you can then render any frame you want using the time output dialog. If you go back and move the time slider then it wont render again until you get frame 0 render[ing] again.

is that as confusing as I made it sound? ...

SJ