View Full Version : Batch render problems (NURBS objects disappear)

04 April 2007, 10:46 AM
Hi -

I'm having a strange problem with my scene when I try to do a batch render.

When I render a single frame (from the render view), I get...

But when I try to render the whole sequence through the batch render command, I get...

...and MOST of my NURBS surfaces disappear. The cord from the bass amp is NURBS, and not attached to an approximation node. The tie-dye poster is NURBS, and IS plugged into an approximation node.

I'm rendering with mental ray, and I have two approximation editor nodes. One for surfaces, and one for trims. I'm tried several settings for each node, but each time it does the same thing in batch render. Anyone have any experience with this? Let me know if I should clarify my setup or give additional information.

Thanks - Justin

04 April 2007, 09:07 PM
Goulash -

It seems that the objects that are disappearing are both NURBS surfaces and are referenced. The bass amp's cabinet shows up (as does both guitar stands) because it's a poly object, but everything else that doesn't render is a referenced NURBS surface. I don't know why that is though to help you out. Hopefully some nice person on this board knows better than I.

Peace - Justin

04 April 2007, 12:07 AM
man, just when i went to post about my own problem. i am having the same problem but in my scene ONLY nurbs objects show up. exactly the same as your problem but the polys go away instead of the nurbs. mabye we can team up! seriously this is a very annoying bug.

i think or hope this may be a maya 8 bug as i have used mental ray for years now and never seen this sort of thing till v.8...

04 April 2007, 06:40 AM
Ian -

Are you referencing any of the objects in your scene? I'm going to try duplicating my referenced objects then hiding them to see if that fixes the problem. It's a workaround though, so I'd still like to figure out what the actual problem is. Do you think it could just be a bug instead of me just screwing something up?

- Justin

04 April 2007, 05:48 PM
We had the same problem a few months ago: referenced NURBS in 8.5 won't batch render.
Sent the Scene to Autodesk and they had to admit that it is a bug.

If anybody finds a good workaround I'd be very interested, because this bug really screws our workflow.

Cheers - Christoph

04 April 2007, 05:59 PM
i cant beleive i havent seen a lot more posts about this. that is one hell of a bug considering nurbs and referencing have to be some of the more used features..

i'm also using references... i'm using version 8.0 though, and my scene only renders the nurbs.. i guess i could render the nurbs in 8 and the polys in 8.5... :rolleyes:

04 April 2007, 09:21 PM
"i'm also using references... i'm using version 8.0 though, and my scene only renders the nurbs.. i guess i could render the nurbs in 8 and the polys in 8.5... :rolleyes:"

Man, that would be funny if this problem didn't suck so much. ;-)

Anyway, I duplicated all of my referenced geometry then hid the actual reference objects (so that the duplicates were being rendered)...that succeeded in producing visible objects. The newest problem is that if I batch render in Maya it works fine, but if I do it from the command line it ignores my render settings (it's all aliased and ugly). I'm going to try tediously duplicating my shader groups next and eliminating referencing altogether to try and fix that, but this is a whole other problem.

I know that this workaround defeats the entire point of referencing, but since I was only referencing objects because I thought it was the "right way", I can afford to change things up in order to reach the ultimate goal...finishing up my demo reel. This bug definately sucks though, especially for you guys who actually use referencing in your production pipeline.

- Justin

04 April 2007, 10:08 PM
is that maya has a pretty solid convert nurbs to polygons function... which can even be part of the construction history so you preserve the original nurb object for editing if need be and it will update the poly copy realtime with tweaks.. its pretty sweet actually.. so if you DO need to use references i would set that up instead of duplicating the objects. i would try doing it in the referenced scene, not the original file, just to keep the original file clean for whenever they fix this bug :)

i wonder what happen with subdivision.. have we all forgotten about them yet? i know i did untill i started wondering about this. i never use them though so i'm not even gonna try :)

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