normal maps

OpenGL OpenGL: Basic Coding
1

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

2

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.

3

I understand perfectly well that OBJ file does not contain a normal map… I’m not so much of a noob… :slight_smile:
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

4

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.

5

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.

6

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.