3d73848d@news.povray.org...
> Do some triangles use one map, and the other triangles a
> different map?

The texture information is carried by the vertices, not by the triangles (or
polygons). Typically, a vertex is linked to a texture and a <u,v> vector for
this texture (there may be cases where a vertex has several texture info
attached, I'm not sure). The material at any point of the polygon is taken
from the corresponding area on the map delimited by the 3 or 4 (usually)
vertices.

It's not so much a question of map than a question of coordinates, actually.
Once a model has uv info, it uses the color found for the required texture
at the given location in the uv plane, and the "map" can be a procedural
POV-Ray texture (between <0,0,0> and <1,1,0>).


> If, so, isn't it very difficult to make the maps match up
> smoothly if the textures are detailed?

In the case of Poser, there are some "seams" maps to help people design the
map to avoid these kind of problems. Basically, it's like wrapping some
elastic cloth over an object. And it's not easy...

The best for you would be to download whatever OBJ file you can find on the
net and run it through uvmapper and see how it works. It's hard to explain,
but I guess that seeing it work is educational enough. You can also have a
look at any of the maps used for Poser models that can be found at
renderosity.

Btw, the tool that hobbyists like us sorely miss is a 3D, interactive uv
painting program a little more sophisticated than uvmapper. There was
something called 3dpainter once, but it's dead and the ones that exist (deep
paint and bodypaint) are quite expensive.

G.

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