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I've picked up the work with designing a new master skin shader. Still early, but I think the results are encouraging so far.

In the image, what you see is a completely procedural shader. No normal map, no diffuse texture.

EDIT: should be "... is a MOSTLY procedural shader".



Specific areas of interest to note:

- The sub-cutaneous color variation
- The skin topology (obviously)
- The scale and properties of the skin topology are fine-tuned for the face independently of the rest of the body
- Topology and color of nipples. Note "wart" bumps around the edge.
- Topology and color of lips. Note creases and ridges.

Difficult to see but still there is that the material will automatically take the character scale into account when, for example, determining the SSS radius scale and the texture scales.

Another difference to the current MPFB skin model is that all this is included in one material. That is, eventhough the lips and aureolae look rather different, they are still parts of the same master skin shader node tree. In the current MPFB skin material, lips and nipples have separate material instance.

Great work, looks really promising. I'm just curious how you addressed the topology problem an a procedural workflow.

Excellent work! Does the shader allow you to smoothly change skin tone and color (depending on race)? It' s a Blender shader, isn't it?

Aranuvir wrote:Great work, looks really promising. I'm just curious how you addressed the topology problem an a procedural workflow.

Actually "completely procedural" was pretty inaccurate of me to say. Or more along the lines of "completely wrong". It's simply not true.

The areas of the body are defined with BW jpeg images. This is for the face:



These are shipped with MPFB2, and I have a solution for creating general system node groups that picks up the path to these area defining images.

So while "no normal map, no diffuse texture" is true, "completely procedural" is not.

Some areas/distances are actually fully procedural though, for example where to place the ring of bumpiness at the edge of the aureolae. This is calculated as a distance from a constant coordinate in UV space. The center of the nipple is always at a specific UV coordinate, no matter which targets have been applied. Thus we can specify that a bumpiness texture shall start, say, 0.08 UV units from that coordinate and end 0.12 from it.

tomcat wrote:Excellent work! Does the shader allow you to smoothly change skin tone and color (depending on race)? It' s a Blender shader, isn't it?

Thanks. Yes, it's a blender material, and every such aspect can be varied.

This is actually the main goal: that the look of the skin can be completely customized without having to create new image textures.

As a side note: it is fully possible to also hook both diffuse textures and normal maps to the shader. It is then possible to say to what extent the diffuse texture should be used over the given color settings for the body areas.

Further additions:

- Ability to tweak color of eyelids (partially hidden behind the eyelashes here)
- Tweaked lips ridge generation
- Skin spot layer for skin imperfections

OK, good know. How many region masks do you use?

The ones that exist so far are:

aureolae.jpg
eyelids.jpg
face.jpg
fingernails.jpg
inside-mouth.jpg
lips.jpg
toenails.jpg

... but I plan on adding at least ears, scalp, genitals, palms and soles too. In a node setup the system textures look like this:



With one such group for each mask.

Some ideas that could improve the workflow:
- Perhaps you should consider to mix shaders instead of colors, so you can control more features like roughness/gloss, SSS or normals.
- I'm not sure how much these textures impact the workload of the gpu/vram. Perhaps it would be beneficial to pack several textures in the red, blue and green channel and unpack them with the separate rgb node in the node editor
- Consider to use a different file format. The lossy jpeg format is probably not ideal.

I am thinking about the possibility of transferring shaders to the game engine.

My guess is that it'd be very difficult to get the blender procedural shader to translate to a godot procedural shader.

However, you should be able to bake the result of the blender procedural shader into a diffuse texture and a normal map and then use these instead.