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heinz85
01-25-2012, 08:41 AM
Hey Guys.
Anybody has an example of a OBJ file with normal map?
I just don't know how to use Blender to generate them myself,
and there are not much OBJ files with normal maps on the web...

Thanks,
Heinrich

Alfonse Reinheart
01-25-2012, 09:04 AM
Normal maps, as the name suggests, are textures. Obj files store meshes. Mesh files do not store texture data. They may store references to textures (the filename of a texture), but not the texture itself.

heinz85
01-25-2012, 09:13 AM
I understand perfectly well that OBJ file does not contain a normal map... I'm not so much of a noob... :)
What I meant is two files:

1) OBJ file representing a mesh model....
2) Aproppriate normal map for it. A texture containing the normals of the surface encoded as RGB values, so I might use these normals when I apply the lighting equation...

Thanks...
Heinrich

McLeary
01-25-2012, 09:16 AM
Try this one.

http://crytek.com/sites/default/files/sponza_obj.rar
http://crytek.com/sites/default/files/sponza_textures.rar

Open the OBJ file in some modeling program (like blender), isolate one object that contains a normal map (like the ground plane) and save that object.

Alfonse Reinheart
01-25-2012, 09:45 AM
It should be noted that .obj files cannot (as far as I can tell) store the tangent-space basis necessary for doing tangent-space bump mapping.

McLeary
01-25-2012, 11:00 AM
Yes, that is right. I use this library http://assimp.sourceforge.net/ in order to read .objs and compute tangents and binormals. It is easy to use and it is able to import various commons formats.