Maya 6.5, Mental Ray and high fur counts

[randomizer]

did one of you guys manage to get rendering of high fur counts (200000) working in mental ray for maya?
i always get crashes when i try to render.
first it gathers a lot of memory (around 1 gig) and then kills maya.
it can't be a memory problem. i have 2 gigs in my system.
i also tried the rapid mode.

[bart]

I wouldn't necessarily say that it can't be a memory problem.
What OS are you using?
Because of the OS, 2G is not really available for the application.
And Windows tends to take up more.

Have you played with the memory limit setting in mental ray Render Globals?

Rapid Motion scanline method, which is now called the rasterizer, is definitely the preferred method for high fur counts.

Bart

[randomizer]

I am rendering on windows.
Setting the memory limit to around 1.4 gigs does not help.
Maya crashes with a runtime error all the time.
I can't even render fur counts of 100,000.

Hopefully i can setup a linux machine soon to try rendering there.

Can rendering via satellites help? Maybe they only use the memory needed for that fragment of the image they have to render.

[bart]

Try reducing the memory limit.

Is the fur all one clump, or broken up?

[randomizer]

It's all in one.
Tomorrow i will give the memory limit a try

[bill spradlin]

Have you attempted to render from the command line? This will free up a good amount of ram without having the gui open. It's kind of a pain to do any testing on, but if all else fails...

Also, what I do for rendering and pretty much any work I do in Windows XP is set up a seperate user account for 3D work only. For this account I shut off all unecessary services and make sure that nothing is loading that I do not need, chat programs, system services etc, uneeded themes and windows bells and whistles i.e. menu shadows/animations etc.

Optmizing the windows swap file is also essential, having the correct settings for it will help tremendously in system memory management.

[randomizer]

I got it working one time but never again. I Don't know why it rendered that time. It was from within Maya.
When rendering from the command line i get the same crashes.
Still got no chance to test it on linux.

[Jackdeth]

Make the memory limit -1, and try turing down the segments on the fur. For short fur, you should be able to use only 1 or 2 segments. Everytime you raise that number, its doubling your fur poly count, so keep that in mind.

[KimSergei]

I have the same problem with Maya 6.5. But in previous version (6.0.1) i sucessfully rendered more than 200000 fur counts

[carsten]

maya has a field for mental ray's memory limit, but you should know that this limit is for mental ray only. if you set it too high, maya uses a bunch of memory, and then mental ray thinks there is lots more, but runs out prematurely.

to set the value, load your scene, and try rendering out a pass without fg with the maya renderer. note the memory usage. then set mental ray's limit to your_memory - noted_usage. note also that your_memory may not be as much as you have in the machine. windows will often refuse to allocate more than about 1.3 GB per process in my experience. if you have more than this, try setting mental ray's limit to 1.3 GB - noted_usage.

if this doesn't work, export your scene to an mi file and render on the commandline, with no programs running. then you could set mental ray's limit to about 1.2 GB.

[dropthatnow]

hi

it might be the wrong 3d app (in this case XSI), but we experienced some weird things when it came to rendertime. some frames wont even render at all. a clean n fresh scene helps a lot.
we got a character with 450000 hairs and most of the times it renders even with motion blur and detailed shadow maps (u must know that XSI 4.2 unlike Maya uses MR 3.3..). it is fully animated with deformations etc.
Very important things to do:
- use the rapid scanline renderer
- use detail shadow maps and not raytracing
- set the memory limit for mental ray to 256mb
- task size 32 or 64 (keep an eye on memory consumption). higher will render faster.
- pray