VRay - xGen Hair tesselation

[DHX_Richard]

Hi All,

I'm trying to understand how to best setup xGen with vRay in regards to strand tesselation at rendertime:

When zooming into a hair system (character's hair for example) and using dynamic tesselation the ram continues to rise the closer I get until I exceed the amount of ram I have available. Is there an upper limit to divisions similar to the max subdivs attribute in subdivision and displament quality for vray subdivs?

The segment length option is a partial solve, low numbers (ex changing from 1 -> 2) seems to give decent results, larger values reveal when the tesselation happens

I can use static tesselation to add a cap to the subdivisions, but then I lose the low end optimization when far away from camera

I'm hoping to set up a scenario where far away the ram footprint is quite small, and when getting close it will tessellate until an arbitary (set) value is reached then hold that. Anyone have any advice on the best way to approach this?

Thanks
-Richard

[moshev]

Hi,

Currently we have no limit to dynamic hair tessellation other than the segment length factor.

[DHX_Richard]

Thanks for the reply Moshev, we'll continue optimizing around dynamic with a >1 px value.

Do you think it would be beneficial to add an attribute similar to .vrayMaxSubdivs but for hair? Or is that just us trying to fit a lot of hair inside a small ram footprint?

Cheers
-Richard

[moshev]

Yes, I can see how it can be useful. I'll try to have it done soon.

[DHX_Richard]

Thanks Moshev, much appreciated!

-Richard