Image/Displacement-based vascularity for Gen3F/M
RenderPretender
Posts: 1,041
I'd love to see image/displacement-based vascularity for Gen3F/M. The current hi-def/morph-based vascularity consistently pales in comparison to the anatomical realism of the V4/M4 vascularity assets that work in the diffuse and displacement channels. Morph-based vascularity also takes abysmally long to render. I'd love to see a content provider address this unfortumate shortcoming of Gen3.
Daz 3D is part of 
Connect
DAZ Productions, Inc.
224 S 200 W, Suite #250
Salt Lake City, UT 84101
Licensing Agreement | Terms of Service | Privacy Policy | EULA
© 2024 Daz Productions Inc. All Rights Reserved.
Comments
For Iray, displacement will take a lot longer to render than the geometry solutions...you need higher levels of SubD to get decent displacement compared to what is needed for the HD morphs.
The HD morphs work well at level 2...the level would need to be 3 or 4 to get similar results to the 3DL displacement.
I don't use Iray... I use 3Delight. And aside from the speed issue, the current crop of geometry-based vascularity solutions are anatomically incorrect (I'm a physiologist), and simply look like bloody hell compared to the image-based ones for V4/M4.
That can be a problem...
But in general, the morph solution is a compromise. It's more restricted to actual geometry than the displacement solution, so yes, some measure anatomical inaccuracy is going to happen. For most, though, just a 'there are veins here' hint is 'good enough'.
And it's more about the capabilities of the renderer than it is the models, anyway. 3DL has always been known for its microdisplacement abilities...and the speed at which it does it. There are very few other renderers that can match it, in that area.
That would not be a reflection of whether they are image maps or HD morphs - either would eb made in much the same way, it's just a question of whether theya re baked to a map or imported as an HD morph. Morphs do have the tremendous advantage of working with any UV map on the base figure, which isn't true of dsiplacement maps. If the existing products are not correct in your view then the best thing to do would be to provide feedback to the creators, via a support ticket or by PM if theya re active on the forum.
Sadly for me. the "veins are there" rationale doesn't work because it kills the authenticity of my characters, and I end up having to do more postwork than usual as an "apologistic" measure. As expensive as Gen3 and its assets are, that should not be the case. That's why I'm hoping a skilled PA will recognize the issue and provide an image-based alternative to the current crop of horrifically inaccurate morphs.
Back to V4 I go for my next piece...
As Richard mentioned there would be no difference between an image or morph based solution. The image can be used for a reference for the morph and you would end up with the same exact result in the HD morph with the all of the advantages. Then it would come down to the quality of the reference. If there are no good references available to the PAs, then it becomes a best guess. As there are several products with veins available, if they don't suit your needs then you may have to make your own if you need exact references.
In terms of realism, morph-based vascularity is dead in the water because it imparts no blood perfusion color, and because geometry does not allow for the granular finesse of diffusion and displacement-based vascularity. Geometry-based vascularity solutions are not - and will never be - equal to the image-based products created for V4/M4. And accurate references are a dime a dozen. The failure is in trying to get geometry to accommodate/replicate the minute features of human vascularity.
The short answer here seems to be that no one really recognizes or acknowledges the obvious shortcoming, so I'm back to V4 for any work that requires anything other than long-focus vascularity.
There are methods to convert your V4/M4 texture assets to the Genesis 3 UV, both manual (there is a good blender tutorial) and semi-automated (such as Cayman Studios' products). Until/unless a texture-based product vascularity product becomes available, perhaps this would be an alternative for you.
Yes, with using LIE you can add the color to the textures...it just will take a bit of working with them to do so. Because the morphs are 'generic' and not tied to a specific texture set there aren't any ready made resources for the color compontent. That's not to say it can't happen, just that it isn't something that's there has been much interest in.
The 'best' set up would be a combination of HD morphs, with displacement/normal maps to supplement those with and the color layers that can be added to any texture set...probably one set needed for each UV set available.
I'm not sure you have been looking in the store as there was a product that used HD veins plus lie for the colors underneath by SimonWM. There is a set for Genesis 2 and Genesis 3. Again, that's the same as using all texture based solutions with the advantages of HD morphs (though if you're using a diffent UV than the vein textures you will have to convert them). Also, unless you have been making your own maps, there aren't many such products for gen4; in fact there was only one and that's gone from the marketplace. There are far more vein products for the newer generations than gen4.
It sounds like the best solution would be a special shader that adjusts the SSS color based on the displacement map for the 'veins'. This would even allow veins with displacement of 0 to still be visible. It would also help with skin color matching, but the resulting shader would probably be pretty slow. But it WOULD give one the 'realism' they need, since it would be simulating the actual subsurface scattering through the vein color below the surface of the skin.
(Important note. IANASG (I Am Not A Shader Guru)....so the actual implementation of this would be best left to someone more skilled. Such a shader should be doable in both Iray and 3DL.)
No special shader needed...just a good set of SSS control maps.
Yes, but by using the existing displacement map for the 'veins' you don't run the risk of them not 'matching up' between color and position. And if you are already using an SSS control map, the shader allows it to be shifted only where the vein displacement map indicates....it only 'adds' more blue/whatever to the SSS color where the displacement map indicates the veins are. Makes it to where you can shift the vein structure just by changing the one map, and a color value (the offset color amount).