Max Hair & Fur Texture

[FSGFX]

Hi!

I am currently rendering fur on an animal with Maxs native Hair & Fur.
I am using 3Ds Max 2010 and Vray SP5 with the mr prim option.

This looks pretty cool - anyway I am having trouble setting the fur color to be the exact color of the underlying diffuse texture of the animal.

As far as I know the only way to color the fur itself is with the "Tip & Root" Color boxes in the material section of the Hair&Fur-Modifier itself.

But as soon as I stick a texture in one of these slots (even a reduced 56pixel version) rendering doesn't start anymore as the PC gets stuck on "Updating Object (HairVrObject1)".

I am rendering 100 000 hairs with two passes on an Intel i7 with 8 gig Ram.
The only way to get the rendering start again is to reduce the haircount to something ridiculous like 15 000.

Any idea why this is - or is there any other way to get the fur to have the color of a texture?

Thanks in advance,
Flo

[vlado]

Can you get me a scene for this to vlado@chaosgroup.com so that I can look at it?

Best regards,
Vlado

[FSGFX]

Hi!

Rendering starts after approximately 10min "Updating Object (HairVrObject1)" with maps applied.
Is there any way to optimize this?

Getting you the scene is a bit tricky, as it is for an ongoing project, which is under a bunch of NDAs.
Any way I will try to recreated the same problems in another scene.

[Dariusz Makowski (Dadal)]

Hey

I dunno how to help you, but maybe u can repeat the problem in new clean scene? That shouldn't affect ur NDA

[FSGFX]

working on it

[FSGFX]

Well - actually it seems that there is nothing special about that scene.
It is just the fact that we are rendering in 720p with around 300 000 hairs and 2 hair passes.
And that this "Updating Object (HairVrObject1)" just takes forever, as it only uses 1 core - therefore even network rendering doesn't help here that much.
Undortunately this has to be done for every single frame and does take considerably longer with maps applied.

What exactly doies it do?
Is there some way to speed this up?

[FSGFX]

Its really a pity!
Once I remove all the maps (color and density) rendering starts after 10 secs - even with 300 000 hairs.

Anyone knows how to deal with this?

Should I try to render the fur with scanline and compose it afterwards?

[vlado]

What kind of maps are they? I'm not sure scanline will deal with this better - the Hair engine is still the same one.

Best regards,
Vlado

[FSGFX]

I am using a greyscale density map to mask certain areas of the animal.
In addition to that we are using a color map in the Root color and Tip color slot, as the animal has different colored hair all around the body.

All maps are tga - we have even reduced the two maps to 128*128 pixel each.

Without maps rendering starts after 10sec.
With maps applied (even the small ones) it takes up to 20min until the "preprocessing" on one core is done - so even our small render farm can't help here.
Maps size does not seem to make a notable difference.

With scanline and all maps applied the fur takes around 2-3min to render - but as it doesn't know Vray lights we would have to relight the whole scene with standard max omnis.

[xoy]

my experience is as bad as yours. as far as i know, that's more like a max thing rather than vray's own issue. i personally couldn't find any solution for that. if you switch the renderer to mental ray, you'll still see the same unbearably long "translation" time. 20 min update time basically echoes my experience with 150~200k hairs. buffer mode instead of mr prim will surely speed up the translation part, but then the actual image render time will be very long compared to prim mode, and you're stuck with all the limitations of hair's own buffer renderer such as clamped integer output, no usable motion blur solution etc. in max, only with mr prim mode, you can have motion blur (either 2d or 3d) and 32 bit float image data. then it's not really usable as it is, since it is wasting so much of your render resources and still unstable.