Advanced UV mapping/ texturing for BGE

Hey! So I’ve created a normal map that I’ve mapped to a low poly object for the game engine, but the problem is, this will only allow me to get the shape, not the materials. I want to UV unwrap the high-poly object to export to GIMP and create the texture to apply to the low poly object, but I’m having lots of trouble with this

Is there a better way to get both the normal map and the UV map or some kind of materials map from the high-poly object easily and efficiently?

I can provide an example if needed

You might want to look into Blender’s baking system, it’s a system that uses tricks like raycasting to project the detail of a high-poly object into a texture that fits the UVmap of the low poly object.

Even then, people have commented that they sometimes have issues with Blender’s implementation, so they simply use an external app. like Xnormal to create their maps.

Yeah, that’s how I created the normal/bump maps, by using bake normals. so there’s no way to effectively UV unwrap a high-poly object to export the image?
Is using external better than baking?

If you’re meaning exporting the layout of the high-poly object to the GIMP to paint over, then I believe there is an option in the UV editor that will allow you to do just that.

As for unwrapping, the best way to unwrap a lot of polygons instantly is to place seams around various parts on the object and use the ‘unwrap’ option in the unwrap menu. If you do that, export the map layout, paint over it, and load the image into Blender, you should be able to apply it to your low-poly object on the condition that the shape is similar enough to be able to match the texture with the UVmap.

If you mean actually transferring the UV unwrap data to the low-poly mesh, you might have to wait until the GSoC project concerning mesh information transfer gets committed to trunk, and even then I’m not so sure. One way to ensure a full transfer of materials with the UV map intact would be to use tools like ‘dissolve’ or the decimate modifier to turn the high-poly object into a low-poly one, as they will preserve your UV information.