Maya for 3D Printing - Rapid Prototyping
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# 1 27-01-2013 , 02:47 PM
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obj file format with multiple textures

Hello,

I have the following problem:

Maya model -> done
Texturing, UV mapping -> done (big house, many objects, the objects were textured separately!, textures are in jpg format)

But there are no lights and shadows at the moment. I need them also. So I decided to add occlusion, global illumination, final gathering and also light to my scenes. But this type of shadowing is adding to the whole model (not to objects, walls, furnitures separately)... Occlusion, FG, GI, shadowing to different pass, saved as TIF format, then make a composition of these different TIF shaders in Photoshop and assign the result to the whole model. The texture is the output, not the input (when I made the texturing, the jpg texture files were my input).

I export the whoel model to OBJ format. There is an obj file, an mtl file, and many jpg files (uv mapping stored in the mtl file).

The question is: how to add this extra shadowing (GI, FG, lights) material (TIF) to the texured model/building? Will this overwrite all the existing textures? Or can I 'multiply' somehow the textures (approx. 100 jpg files) and the shadows (1 TIF file)?

How to continue?

Thanks for the answers...

# 2 27-01-2013 , 04:51 PM
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You pretty much lost me here:

...
But this type of shadowing is adding to the whole model (not to objects, walls, furnitures separately)... Occlusion, FG, GI, shadowing to different pass, saved as TIF format, then make a composition of these different TIF shaders in Photoshop and assign the result to the whole model. The texture is the output, not the input (when I made the texturing, the jpg texture files were my input).

...


Sounds like you want to bake lighting information into textures then combine those textures in Photoshop to use in a realtime application (I'm guessing). How safely the obj file format can transfer those assignments in the target program is another issue. But yeah, look into baking textures.


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# 3 27-01-2013 , 05:07 PM
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Yes, baking textures is the target I want to achive.
But I read in another site, that obj does not supports two sets of texture coordinates.
The .x format supports this, but I don't have a converter.
Maybe this fileformat would help me... Is somewhere a working .x exporter for Maya (2012, 64bit) ? I would like to give a try also for this ...

# 4 27-01-2013 , 05:23 PM
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Or an another solution (maybe)...

In the model there are many objects, each textured separately -> OK
When I combine all the objects/polygons, then the textures are still the same -> OK

But if I would like to create a new UV map to the combined object, the UV editor does not recognizes all the textures, so the UV map is useless in case of combined objects (like in my case)...

Can I somehow create a UV map, where the textures and their position/map remains the same? Because if Yes, what I need only to multiply the texture map with the shadowed one...

# 5 27-01-2013 , 11:41 PM
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If the UV shells for the objects are in the same space then yes, that would cause overlapping issues when you combine them all into one mesh. You may want to look into creating UV tiles and see if they'll cause problems in your workflow. If you gave more info on your desired end result then maybe someone else can help you as I don't have experience with realtime output.


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# 6 28-01-2013 , 08:58 PM
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