[WIP] Buster the..bust + Skin texture
Heya
Would love some more crit on a wip bust (i posted this a while ago), and instead of bumping the old thread i thought i'd share how i try to polypaint realistic (i hope) skin textures from scratch. Realistic skin is a bit of a mindfuck, and i want to share a bit of my research - just dont hate me too much, my anatomy isnt the sharpest
Zbrush BPR render. Lit Diffuse only.
Sub Surface Scattering
The Ecorche/SSS approach to skin painting tends to be more common in film/animation studios. It takes much longer, but the control over your texture can often be well worth it.
When light hits the skin its not just reflecting the pigment and features on the top. Because flesh is relatively translucent, that light is often bouncing off multiple 'layers'. The first and most prevalent is the skin/pigment, then there is the blood vessels, muscles, insertion points, and bone. All of these elements are very subtle in a final skin texture, but when they aren't present, skin can look dead and lifeless - often giving characters a one way ticket to the bottom of the uncanny valley.
Now in the case of an animation studio you'd store each pass/layer as a separate texture for use in an SSS setup, but for most game models i just layer the paint - although it does help to save your layers.
I jump into flat shading, or knock the opacity on my standard zbrush shader/mat right down. Seeing a few details on what i'm painting help me, especially with the wrinkles on this guy - but you want to see the most accurate representation of the color.
Back Scatter
The back scatter layer is the deep muscle tissue and bone. The closer bone is to the surface the whiter it is. IE the collarbone. This pass i'm usually really sloppy and quick with, i use a spray brush that mottles the texture rather than shading neatly. The mottling and roughness comes in usefull later. The deep reds indicate muscle tissue, blending between the bone and muscle with an orange (to show shallower muscle or insertion points) is good practice - but its a cumulative process and you can do it in the next step.
Sub-Dermal
Sub-dermal is usually a variety of textures, but for the sake of simplicity/speed we'll say it deals mostly with flesh/blood just under the skin. As a result of the depth, its much more prevalent in the texture and much more important. You get the colors not usually associated with skin in this layer; purples, greens, yellows etc.
First i give the model a ~10% glaze with a whitish pink color (saves painting over all the red), then i get the blue/purple and go to town on the more bony areas. I think the mouth and eyes are especially important. I give warmer colors to muscles, whilst still trying to keep the white of the more important and closest bone landmarks. (Nose bridge, collarbone, zygomatic process, ear ridges etc). I add very little yellow and green, but blending between sharper blue and red areas is useful. I still keep the brushes heavy and messy for the mottled distortion. I never use the smoothing brush.
In this layer you can also add blood vessels.
Final Base
I'll glaze the model with a uniform pinkish (although this is obviously race dependant) hue, then go over it again with the spray brush to keep the mottling. I use much much softer orange and purple brushes to accent the areas i think need it. Usually lips require more purple than they get during subdermal. I work my way down in spray size until i get the result im looking for; generally something that's still noisy but not messy.
Remember this isnt a finished texture so much as a base. With your new base texture you can add the blemishes and details like pores, moles and freckles, stubble and dirt. Woot.
Fin
and thats that. Its a slower method, but the control and added realism i think is really nifty. If you're after more (and better) tutes i'd really recommend Scott Spencer's books and the character portrait videos by eat3D. Freaking awesome. Any anatomy book as well:)
Cheers.
(If this post helped you, or you feel like helping out a fellow polycounter - check out http://www.originsmmo.com/ an Indie project I'm a part of. Every website hit and facebook like is inching us closer to a release. We're also recruiting. Peace!)
Would love some more crit on a wip bust (i posted this a while ago), and instead of bumping the old thread i thought i'd share how i try to polypaint realistic (i hope) skin textures from scratch. Realistic skin is a bit of a mindfuck, and i want to share a bit of my research - just dont hate me too much, my anatomy isnt the sharpest
Zbrush BPR render. Lit Diffuse only.
Sub Surface Scattering
The Ecorche/SSS approach to skin painting tends to be more common in film/animation studios. It takes much longer, but the control over your texture can often be well worth it.
When light hits the skin its not just reflecting the pigment and features on the top. Because flesh is relatively translucent, that light is often bouncing off multiple 'layers'. The first and most prevalent is the skin/pigment, then there is the blood vessels, muscles, insertion points, and bone. All of these elements are very subtle in a final skin texture, but when they aren't present, skin can look dead and lifeless - often giving characters a one way ticket to the bottom of the uncanny valley.
Now in the case of an animation studio you'd store each pass/layer as a separate texture for use in an SSS setup, but for most game models i just layer the paint - although it does help to save your layers.
I jump into flat shading, or knock the opacity on my standard zbrush shader/mat right down. Seeing a few details on what i'm painting help me, especially with the wrinkles on this guy - but you want to see the most accurate representation of the color.
Back Scatter
The back scatter layer is the deep muscle tissue and bone. The closer bone is to the surface the whiter it is. IE the collarbone. This pass i'm usually really sloppy and quick with, i use a spray brush that mottles the texture rather than shading neatly. The mottling and roughness comes in usefull later. The deep reds indicate muscle tissue, blending between the bone and muscle with an orange (to show shallower muscle or insertion points) is good practice - but its a cumulative process and you can do it in the next step.
Sub-Dermal
Sub-dermal is usually a variety of textures, but for the sake of simplicity/speed we'll say it deals mostly with flesh/blood just under the skin. As a result of the depth, its much more prevalent in the texture and much more important. You get the colors not usually associated with skin in this layer; purples, greens, yellows etc.
First i give the model a ~10% glaze with a whitish pink color (saves painting over all the red), then i get the blue/purple and go to town on the more bony areas. I think the mouth and eyes are especially important. I give warmer colors to muscles, whilst still trying to keep the white of the more important and closest bone landmarks. (Nose bridge, collarbone, zygomatic process, ear ridges etc). I add very little yellow and green, but blending between sharper blue and red areas is useful. I still keep the brushes heavy and messy for the mottled distortion. I never use the smoothing brush.
In this layer you can also add blood vessels.
Final Base
I'll glaze the model with a uniform pinkish (although this is obviously race dependant) hue, then go over it again with the spray brush to keep the mottling. I use much much softer orange and purple brushes to accent the areas i think need it. Usually lips require more purple than they get during subdermal. I work my way down in spray size until i get the result im looking for; generally something that's still noisy but not messy.
Remember this isnt a finished texture so much as a base. With your new base texture you can add the blemishes and details like pores, moles and freckles, stubble and dirt. Woot.
Fin
and thats that. Its a slower method, but the control and added realism i think is really nifty. If you're after more (and better) tutes i'd really recommend Scott Spencer's books and the character portrait videos by eat3D. Freaking awesome. Any anatomy book as well:)
Cheers.
(If this post helped you, or you feel like helping out a fellow polycounter - check out http://www.originsmmo.com/ an Indie project I'm a part of. Every website hit and facebook like is inching us closer to a release. We're also recruiting. Peace!)
Replies
Some extra links:
[ame="http://www.amazon.com/gp/product/0470450266/ref=pd_lpo_k2_dp_sr_3/187-5192075-7578023?pf_rd_m=ATVPDKIKX0DER&pf_rd_s=lpo-top-stripe-1&pf_rd_r=00HV1NZ6N75QY97B1JX9&pf_rd_t=201&pf_rd_p=1278548962&pf_rd_i=006076015X"]Amazon.com: ZBrush Digital Sculpting Human Anatomy (9780470450260): Scott Spencer: Books[/ame]
http://eat3d.com/maya_portraits