Hair on it's own texture map?

jeremiah_bigley

Hey guys I am working on a character that has a goatee and was wondering if it is justifiable to have the fur tiles on their own texture sheet. Yeah it is another texture call... but for straight portfolio work? Guess I just kinda wanted the fidelity in the hair rather than crunching the hair down to mush in the unwrap...

I didn't leave much room for them and I have already cast and rigged him

LoTekK

If you were to show the flats for that, I would expect an AD to see a goatee living on its own dedicated texture sheet and go "hmmmm?"

Modifying the unwrap shouldn't affect the rigging/weighting, though, no?

jeremiah_bigley

yeah I guess you are right about the modifying after rigging... but I guess it was more the need to recast. You answered my question though. I thought is was a bit extreme myself.

choco

Most people use another texture map for the hair, to use it for a multi-material setup. Skin shader (sss etc...) Hair shader (anisotropic spec/lighting). Can also be used the way you said. (Higher resolution textures).

odium

Yeah I thought it was pretty standard practice to use another sheet for hair?

Farfarer

If it's got an alpha and the main sheet doesn't, I don't see much of a problem, so long as the beard's using a different material anyway.

jeremiah_bigley

so go for it? the main body of the character is a 4096 x 2048 and doesn't need an alpha outside of the hair. So I could dedicate a 512 maybe?

Ace-Angel

Problem is you cannot bake an anistropic map as far I know properly, which is what gives the bending sheen of hair.

Plus, Alpha can get pretty expensive on a bigger texture, so a 512 with an Alpha, with hair all pointing in one direction for Anistropy is all you need for decent looking hair.

Farfarer

Painting anisotropic maps for hair isn't too big a deal. Bake a normal map of a sphere onto a flat plane and you can just colour pick the hair flow direction you want from that and paint away...

gsokol

Yea, separate map is fine.

Sometimes having a complex model with one small part having transparency can cause alpha sorting issues with itself. UDK handles this pretty well, but not all rendering engines do.

Also, having it on its own smaller map has its performance gains, even though your adding another texture lookup. Transparency is expensive, and even if you only have a single pixel that is supposed to be transparent on a texture, the renderer has to look at the transparency value of every single pixel. In that case, its kind of a waste to have a larger texture with a small area of transparency..compared to just having a smaller map for transparent objects.

jeremiah_bigley

Cool stuff. Thanks for the clarification guys. I went with the extra map. Really appreciate the timely feedback everyone gave.