How do I design TripleA hair cards with Zbrush and 3D Studio Max?
polycounter lvl 2
A hair card is made up of:
1. Diffuse (aka albedo, base color, etc)
2. Mask (aka alpha, transparency, opacity, whatever you want to call it)
3. Normal Map (made in xnormal)
4. Specular (made in ???)
Should the shadows be baked into the diffuse aka albedo or am I supposed to create a:
5. Self Shadowing Map?? Which controls the self shadowing on hair strands based upon direction of light in game?
Do I need a:
6. Depth map?? for hair?
1. Diffuse (aka albedo, base color, etc)
2. Mask (aka alpha, transparency, opacity, whatever you want to call it)
3. Normal Map (made in xnormal)
4. Specular (made in ???)
Should the shadows be baked into the diffuse aka albedo or am I supposed to create a:
5. Self Shadowing Map?? Which controls the self shadowing on hair strands based upon direction of light in game?
Do I need a:
6. Depth map?? for hair?
Replies
But in general I'm trying to figure out what maps are used in modern games.
For example in Skyrim, there are no shadow maps or depth maps. Just a diffuse, normal and a mask. Skyrim came out in 2011 I believe.
Do I even need a specular map or is the normal map supposed to handle how light is shown on the hair?
as for rendering features they will depend. the unreal shader looks tasty so if you create your assets with that in mind then why wouldn't you want all the maps they use? i'd expect most games to use less though, there's usually a bit of a difference between a demonstration of what's possible and a shipped game.
to create convincing hair it'll be important to think about how to lay out the geometry and use your UV space first and foremost though. e.g. things that i often see done wrong is a messy hairline that intersects with the skin or unnatural hair density, lack of fly-off hair strands, too obvious copy-paste of hair elements, no comb/growth-direction in the haircut, lack of color variation across the haircut, hair not looking crisp, visible difference in texture resolution within haircuts or when compared to facial hair, etc.
the tech features solve none of those.
1. maximize uv space
2. don't let anything intersect with skin
3. add fly away hair strands
4. ensure proper hair direction
5. ensure color variation
6. don't warp or scale the hair texture too much which ruins crispness in photo shop
Thanks for the above help, I'll focus on these basics first.
re - 2.: it's not like you can't let hair geo intersect with the skin but the way some do it where a bunch of thick hairstrands are just suddenly popping out of the scalp, creating a harsh transition, just looks like bad CG. if you look at a hairline you can usually see a very gradual buildup of density, length and thickness, try emulating that. also helps to paint the skin dark underneath to support the alpha cards/bake down the hair texture information onto the skin.
for 'big' hair it's worth it to experiment with solid geometry as a base layer to make hair appear to have volume and just drape hair cards over that.
i'll be playing around myself with that unreal shader for sure in the near future!