Better scalp for hair (Geograft or geoshell)
Noah LGP
Posts: 2,589
Hi,
The most of time the scalp is passing through the head and requires manual adjustment.
It would be nice if there were scalps as geograft common to all the hair items, just the vendor would create their material/UV set for the scalp and the fibermesh fitted to this scalp.
Post edited by Noah LGP on
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The skin part wouldn't fit/blend to the character skin though.
It's not a big problem, the existing geograft products provide a script which copy the material of the figure. Note if the surface name is the same as the figure, applying a material preset will change the geograft skin too (like Legacy UVs geograft).
The scalp hair texture could be a Diffuse Overlay or LIE preset or a geoshell (if the UV set is different).
why not have a hair without a scalp then and a geoshell or LIE scalp hair?
makes fitting to odd morphed heads easier too
Yes, it would be easier to do !
You'd still have to use LIE or Diffuse Overlay to blend it into the base skin texture or you'd still have a line there where it switched. A tight geoshell would probably be the easiest solution.
That's a great idea, Wendy!
All great suggestions, I like the idea with the GeoShell Scalp. I thought about and just tryed it myself while making some tutorial screenshots to show how it can be done.
At first my biggest concern was about the default UV set "Base Female" of the genesis figures that has the UV seams on the head. The scalp area is divided into the surfaces Face and Body and the second is even split in half and has a much lower texture resolution. I have a shaved hair GeoShell product in my library that shows exactly this difference in the Torso and the Face UV map. See the attached screeshots for that.
Blender Hair ScalpUV G3F
So I went further and loaded everything in Blender and compared the UV map of a scull cap of another hair (Brady Hair) with the default genesis 3 female Base Female UVs.
In Blender there is a Modifier that I used called Data Transfer that works like the transfer Utility in Daz Studio but it can also project UV maps. In the image series you can see I've tried different things but finaly I've used that modifier to "transfer" the Brady Hair scull cap UVs to the genesis 3 figure head mesh. The thing is the PAs would need to agree to use some default scalp UV map provided by Daz for new hair products preferable all the same for the different Genesis generations and gender. Otherwise you have alot work to do to project different scull cap UVs from various PAs and hair products all to the desired Genesis figures. Once you have the scalp UVs of the original hair on the genesis figure you can use the original hair textures for your GeoShell.
DazStudio Hair ScalpUV G3F GeoShell
I had exported my genesis 3 female OBJ from Blender with the scalp UV. Next in DazStudio I've loaded the UV-set and created the Geoshell. In the Prameters pane Property Group "Shell" you see there is a long list of Visibility buttons to help you hiding unneccesary parts of the GeoShell. What confused me at first is that I had to enable not just the Face and the Body surfaces but also the Head ..em Region? to have some ski mask like visibility on the GeoShell. In the end I've deleted the original scalp geometry from the hair and replaced it with the GeoShell scalp and the original textures.
You can click on the title or any thumbnail image to jump to the imgBB gallery. In the gallery page there are arrows on the left and right edge to scroll trough the image series showing everything step by step. I tried to show the difficulties with the UV map and solutions. I hope at least some can follow along and find it useful.
Blender Hair ScalpUV G3F - imgBB Gallery
DazStudio Hair ScalpUV G3F GeoShell - imgBB Gallery
Wouldn't a geograft scalp suffer the same problem of poke through that existing scalp meshes do? If the head is not the same size/shape as the geograft, then surely there will be pokethrough.
A GeoShell is always the exact clone of the figure mesh so it will automaticly adapt to any shape or mesh resolution you will set the figure to. The GeoShell has a slider Offset Distance (cm) under General>Mesh Offset where you can define the distance of the GeoShell the slider tells its measured in cm so the default slider value of 0.1 means its 1mm away from the figure surface. See this screenshot https://i.ibb.co/ggYn9tM/Daz-Studio-Geo-Shell-Scalp-UV-G3-F-22.png.
I can imagine only one scenario in wich you may see poke throughs and that may be the case if you have a character texture loaded on the genesis figure that uses strong dispacment maps in the shader settings that will push the figure head surface through the GeoShell that dosn't use these dispacment maps. In this case you just have to adjust the GeoShell Mesh Offset to get rid of these poke throughs.
Another way to prevent poke throughs with original hair scalps is to use Edit>Figure>Geometry>Add Smoothing Modifier.
I've talked about this here: Scalp on certain hairs showing on face as grain shadow
It doesn't solve the problem because the scalp is partially bigger than the head. It's always strange to see shaved hair at 1 inch of the head sides.
The scalp always need to be adjusted to the position and the shape of the head.
That's why I'm looking for something more reliable no matter the figure I use.
Well if you want shaved hair, the two geoshell hairs from G3 are https://www.daz3d.com/shaved-hair-for-genesis-3-male-s and https://www.daz3d.com/shaved-hair-for-genesis-3-female-s
Since the UV is the same, they work on G8s as well. Quite nicely I think. But you could certainly use it for a scalp.
Yeah this is the shaved hair GeoShell from bluejaunte that I showed in the screenshots. Unlike the viewport preview once rendered you don't see the difference in resolution between the Face and the Torso map.
Like written in the description to compensate the difference in resolution the opacity maps for the torso have 8k resolution and the face maps have 2k. You can use the shaved hair as a scalp there are no material presets but you can set the desired hair color in the surfaces pane to match it as a scalp for other hairs.
But using the default genesis UVs with the seams and two texture maps is not that practical that is what I wanted to show.
Actualy I think most hair items would work without a scalp. It's just there to avoid seeing any bald scalp depending on the densety and opacity of the hair strands.
The hair I've lent the scalp UV from is Brady Hair for Genesis 3 Female(s) from goldtassel. But by looking at other hair products from goldtassel in my library I can see the scalp UV seems to be the same on all of them. This will allow me to use my UV set on the Genesis 3 Female for to replace all of goldtassels hair scalps with GeoShell ones. I just have to save the original shader once and apply it to the GeoShell to have all shader settings and textures like in the original.
GeoShell poke throughs?
About the Offset Distance (cm) slider under General>Mesh Offset: 1mm is not much it's 0,03937 inch and I don't know how far a completly white pixel on the displacement map would elevate the surface with the default shader settings Displacment Strength 100% maybe it would never reach 1mm in height. It was just my guess that even GeoShells can show poke-throughs maybe this is not the case since technicaly it could also be that the displacement map is first applied to the figure and after that the GeoShell is cloned as a layer and will even adapt to the displacement. This is something to be tested or to ask someone at Daz.
Smoothing Modifier
I've used the Smoothing Modifier before on hair not just to make it fit better but also in combination with DFormers to reshape it some. One trick to shrink the hair to get it closer to the head is to create a DFromer, scale the influence field until all hair is red, then scale down the DFormer. That works far better than to scale down the hairs head node because you can still move the DFormer Base around to define the origin for the scaling. While doing this the Smoothing Modifier will prevent any intersections of the hair with the figure while deforming the hair at least if you raise up the Collision Iterations. You can also "bake" the resulting shape of the collision to a morph by exporting an OBJ and importing it back with Morph Loader Pro and the Attenuate options thats what I did in the past to have better fitting hair on my character shapes.
Maybe this is an idea for another tutorial but I guess this will be better showen in a video.
PS: The Smoothing Modifier can help alot to fit everything over everything you eventualy just have to set the Collison Target manualy and turn up the Iterations at first I was surprised what it can do. It will collide with subdivided mesh set as Collison Target but will ignore the mesh resolution set by the SubD modifier in the fitted geometry (I guess for better performance). My fist experiment a while back was fitting a shpere over a cube. Or just for fun how about to force the Force Hair to fit over a sphere lol that is looking strange but shows its possible.
In fact I submit this request because several items like Stylish Shaved Hair For Genesis 3 And 8 Male(s) require manual adjustments.