Loading in .obj & .mtl files

Question

HI all, I'm quite new to Java3D and 3D graphics and I'm struggling to understand how to load in models correctly. I have the latest Java3D binaries, Java 6, and I'm using Flux Studio 2.1 (as I'm also interested in X3D).
Ok the problem. I can import an .obj file into Java3D and have it displayed on the canvas. The object seems to require a texture to be visible; if my knowledge serves me correctly without a texture it may not have a material which enables lighting (could be wrong). Anyway. Loading in a single cube with a brick texture is fine. The moment I make a simply roof with a different texture and attached to the cube (the walls), the geometry loads in Java3D but it uses the first texture (the brick) to cover both the walls (cube) and roof! I don't understand why this second texture has vanished.
I've never looked at an .obj file before but after having opened up the .mtl file it looks like a line is missing:
# File produced by
newmtl dad_Roof
Ns 4
d 1
illum 2
Kd 1.000000 0.000000 0.000000
Ka 0.200000 0.200000 0.200000
Ks 0.000000 0.000000 0.000000
newmtl dad_Walls
Ns 4
d 1
illum 2
Kd 1.000000 0.000000 0.000000
Ka 0.200000 0.200000 0.200000
Ks 0.000000 0.000000 0.000000
map_Kd stonetile10.gif
There is no map_Kd (not sure what it is - must be a texture) entry for the dad_Roof which is being referenced in the .obj file.
I have tried putting in my own map_Kd entry, but it does nothing. Help! :-)
Incase it's something to do with my Java3D code, here's a very simple example of what I am using:
ObjectFile objFileLoader = new ObjectFile(ObjectFile.RESIZE);       
        File modelFile = new File("D:\\Profiles\\aan025\\My Documents\\test.obj");
        URL url = null;
        try {
            url = modelFile.toURI().toURL();
        } catch(MalformedURLException exp) {
            exp.printStackTrace();
        try {
            Scene scene = objFileLoader.load(url);  
            branchGroup = scene.getSceneGroup(); 
            analyseBG(branchGroup);
        } catch(FileNotFoundException exp) {
            exp.printStackTrace();
        return branchGroup;Thanks very much. I'm really enjoying Java3D and 3D modeling.

Answer 1

Has anyone had any luck in loading multiple textures from an .obj file?
Take one obj file, along with a .mtl file. Load it via ObjectFile into the latest Java3D. The scene should be two shapes with a different textures each i.e., two different .jpg files. Can this be done? Or is it one texture per Shape3D loaded in from the .obj and .mtl file?