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Dirk
03-30-2007, 10:16 AM
I want to texture a character with several skin areas. For example, the nose and the skin around the eyes shall have different colors and bump maps, and the skin on this areas shall blend with the the "normal", underlaying skin.

I've set up weight maps for these areas, and want to use procedural textures. However, since the borders of the weight maps get "harder" the higher the subdivision setting of the object is, I need to bake the surface into a UV map.

Now, there are several routes possible:

a) create a full UV map for the character, and bake the whole surface into several high res UV textures (color, specular, bump, etc.). I have no real idea how big the textures should be and how close the camera can come to the character.

b) create a partial UV map in black and white for every weight map, and use the texture as an alpha map for unterlaying procedural surfaces. For example, create a UV map that includes the nose and some polygons around it. But I don't know if this could produce problems at the borders of the UV maps.

c) create a full UV map, and bake several black and white UV textures (one for each weight map that defines an area, like the nose for example), and use them as alpha maps for underlaying procedural textures.

What would be the best way?

Surrealist.
03-30-2007, 01:14 PM
Have you tried a search for some of Dave Jerrard's posts on this? He has some very interesting texturing ideas for weight maps.

hrgiger
03-30-2007, 10:02 PM
Pooby did something like that with a face model. UV'd it it parts and then blended the parts together with weight maps. Not sure I completely understood the process but it seems like it would be great for parts that are normally prone to stretching and pinching on a typical UV projection like the nose.
The thread is here:

http://www.newtek.com/forums/showthread.php?t=22193

gerardstrada
03-31-2007, 01:06 AM
...I've set up weight maps for these areas, and want to use procedural textures. However, since the borders of the weight maps get "harder" the higher the subdivision setting of the object is, I need to bake the surface into a UV map...


That happens when you select an area and apply the weightmap.

http://imagic.ddgenvivo.tv/forums/weightmaps/1.png

This is because the vertices of that area have a weightmap value, but the nearest vertices of this area has no weightmap applied. When you increase the subdivision level, the range is widespread from the higher to lowest values, between the vertices with no weightmap applied to the nearer vertices with some weightmap value:

http://imagic.ddgenvivo.tv/forums/weightmaps/2.png

so you get sharp borders in your weightmaps

http://imagic.ddgenvivo.tv/forums/weightmaps/3.png

To avoid it, apply the weightmap to whole mesh (set 0% for the initial value).

http://imagic.ddgenvivo.tv/forums/weightmaps/4.png

0% for a weightmap is different that no weightmap value. Then, paint or adjust the value for this weighmap according to the areas you want to affect.

http://imagic.ddgenvivo.tv/forums/weightmaps/5.png

In this way when you increase the subpatch level, your weighmaps borders won't get sharper since the whole mesh has the weightmap applied, but only the areas that you want to affect will have a value different to 0%.

http://imagic.ddgenvivo.tv/forums/weightmaps/6.png

If you want even smoother weighmaps, you can use FIsWMapBlur (http://www2.ocn.ne.jp/~fis_junk/plug/win/FIsWMapBlur-i-0_2_0.zip). In surfacing phase, set your gradient parameters: 0 - 0 - 100

http://imagic.ddgenvivo.tv/forums/weightmaps/7.png

This doesn't mean that you don't need UVmaps, you can need them for sure, but for other reasons :) If that's the case, you can select the areas that you want to UVmap (to avoid projection deformations and keep the maps size reasonable) and blend them using weightmaps. Just consider nearest UVmaps should share the some polygons in order to get the proper mix.



Gerardo

gerardstrada
03-31-2007, 01:20 AM
Sorry for my terrible spelling but I'm not able to edit my posts.



Gerardo

Dirk
03-31-2007, 03:37 AM
@gerardstrada: Hey, big thanks!

That's what I was looking for :D

I can dump the whole idea with the UV maps - that's great, many thanks

:) :) :)

SplineGod
03-31-2007, 12:08 PM
I usually start with creating a basic skin using gradients and procedurals. You can use weight maps as alphas to change blend in other procedurals so that the skin texture changes between each region. I would keep this part as simple as possible since it can become quite complex blending all those layers.

On top of that you can also create UV map(s). Those can be separate and/or overlapping areas that can be blended using weight or alpha maps.

The procedurals can also be baked onto image maps and further processed in a paint program.

Again, keep it simple. Sometimes its easy to get caught up in the technical aspect rather then focusing on the artistic aspect. :)

Dirk
04-01-2007, 02:57 AM
It's important to know that with every new bump layer, even if it has its "alpha wmap", the overall "height" of the bump map can change. This can cause trouble if gradients are used for color / specular, etc. It's a good idea to start with the bump map and create gradients after that.

gerardstrada
04-02-2007, 03:52 AM
Those are very useful tips, guys!



Gerardo

Dirk
04-03-2007, 04:04 AM
But Your tip was the most useful I've got for quite some time :D

So here's another one in return: sometimes, UV borders show up when using wmaps as alphas for UV bump textures. But with Blending mode set to "PShop Exclusion", they don't....