how export texture coordinates?

I’m working on a 3D application right now and I use Blender to create 3D models. The created models I export into the Wavefront Obj format to import into my application.

But how can I export the texture coordinates that Blender uses to render the textures?

If I create a new Box for example and export this Box into the Wavefront Obj format, there are no texture coordinates. Only if I go to “Editing” and than in “Mesh: UV Texture > New” I export texture coordinates.

But this don’t work if I subdive the mesh. For example I have a plane and I add texture coordinates with “Mesh: UV Texture > New”, the tex coordinates will be:

vt 0.000000 0.000000
vt 1.000000 0.000000
vt 1.000000 1.000000
vt 0.000000 1.000000

If I than subdive the plane in more vertex/faces I still have the same tex coordinates.

My short question ist: How can I export the tex coordinates per face, so I can use the exported coordinates in my program to render the object as it would be in blender?

Thanks and sorry for my bad english, I’m from germany.

if you change your model ater doing a UV map i think you need to redo your UV map as per the new mehs

so in other words you do your UV map only when the mesh if done and completed you don’t change afterward then the UV coordinates can be exported and will be as per your UV mapping!