Hi there,

I’m having some serious problems with MR’s mrPrim rendering of Hair&Fur in Max 2009 (x64 on Vista Business x64).
I don’t know what else to set up so that I get rid of the juggies and “noise” feel in the hair regions?! It’s driving me crazy and the rendertimes are already way above my limits.

Does anyone know any tips/tricks?

The settings for AA are 1x16 (min x max), total depth sampling is about 20. The hair is setup for 10 passes, 16 segments and the voxelization is set to 10. But still, I can’t get rid of the artifacts. The redertime, btw. was about 3.5 hours for this UNFINISHED render!

Any tip/trick would be much appretiated, thanks in advance,

- loocas

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what type of lights and shadows are you using?

danpool 05 August 2008 04:24 AM

what type of lights and shadows are you using?

There are four lights, two with Shadow Maps (mr) and two with Raytrace Shadows.

loocas,
I’ve tried mr prim every which way while working on a series of Ice Age mammal restorations.  I simply could not get it to ever look right and the render times became extraordinarily long as settings were increased for higher quality (that on a dual quad core).
I wound up going back to scan lne

From the help file

Aside from the “mr prim” option that you can choose as a render effect (see Hair and Fur Render Effect), no mental ray hair shaders are provided with 3ds Max. This feature is meant to support third-party hair shader products or custom-coded hair shaders.

and

mr prim - Hair is generated by a procedural mental ray shader that generates mental ray curve primitives directly into the mental ray rendering stream at render time.

Im not sure how to read this - but since no one seems to be able to get mrPrim working it take it to mean “yes you can use it, but nothing ships that can be used with it”

just found this too http://area.autodesk.com/for...l-leaks-in-alpha-channel/ which makes me think you can get good results somehow…

Max 2009, 2010 32/64
VistaP 64 SP1
Intel Q9550 8GB
ATI 4870x2
Patriot 128GB SSD

MeltingPoint 06 August 2008 04:31 AM

From the help file

Aside from the “mr prim” option that you can choose as a render effect (see Hair and Fur Render Effect), no mental ray hair shaders are provided with 3ds Max. This feature is meant to support third-party hair shader products or custom-coded hair shaders.

and

mr prim - Hair is generated by a procedural mental ray shader that generates mental ray curve primitives directly into the mental ray rendering stream at render time.

Im not sure how to read this - but since no one seems to be able to get mrPrim working it take it to mean “yes you can use it, but nothing ships that can be used with it”

just found this too http://area.autodesk.com/for...l-leaks-in-alpha-channel/ which makes me think you can get good results somehow…

Thanks for your reply, but unfortunately, I’ve tried all the other rendering methods of Hair&Fur and since mrPrim seems to be the closest one to what quality I’m after, I don’t want to use GBuffer rendering.

Btw: the link to my other thread was a bug report, which has nothing to do with the rendering quality I’m after here :)

loocas 06 August 2008 06:44 AM

Thanks for your reply, but unfortunately, I’ve tried all the other rendering methods of Hair&Fur and since mrPrim seems to be the closest one to what quality I’m after, I don’t want to use GBuffer rendering.

Have you tried to use the Fast Rasterizer? I always recommend that when working with hair (or any micro-geometry) because it excels in resolving geometry finer than it resolves shading.

My tests indicates it gets around this issue!

See my blog....

/Z

MasterZap 06 August 2008 12:09 PM

loocas 06 August 2008 06:44 AM

Thanks for your reply, but unfortunately, I’ve tried all the other rendering methods of Hair&Fur and since mrPrim seems to be the closest one to what quality I’m after, I don’t want to use GBuffer rendering.

Have you tried to use the Fast Rasterizer? I always recommend that when working with hair (or any micro-geometry) because it excels in resolving geometry finer than it resolves shading.

My tests indicates it gets around this issue!

See my blog....

/Z

I’ll definitely give it a try as I’m not sure I’ve used the fast rasterizer, but based on your results, it seems that I have not! :)

Thanks for the tip, I’ll post my results here as soon as I get to rendering it.

So I just modified the settings as you suggested, MasterZap, but I’m still getting the “jittery” feel to the hair :( I’ts better, though, but still not quite there yet.

Besides, it introduced an arror in a missing bucket. Everytime the same. Don’t know why.

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Oks, so after increasing all the possible settings quite a lot, I’m at a point where I could consider using the hair, even though it still has this noisy feel to it as well as strange hair strand overlays (possibly due to the sampling of Hair&Fur).

But, the rendertime was quite high 1:24min on a Quad Core machine with 8GB Ram. This isn’t very animatino-friendly, altough I was using two area lights without which I could live perhaps.

But the next real big problem is the error, introduced in rendering the hair clusters. I’m using two hair groups and each of them produces a missing bucket. Every time the same. This is a serious problem, I can’t imagine sending this setup to a renderfarm and realize the next morning that all of the frames are suffering from this bug! I’d die the moment I saw it!

cheers,

- loocas

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what BSP type are you using? just a random thought but try different ones (BSP2 for example). you never know

alex york
for and on behalf of Atelier York | Bespoke Architectural Visualization
http://www.atelieryork.co.uk
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