Multi-material objects in jME3

Troubleshooting graphics
1

I have a single object consisting of four submeshes. Each submesh has its own material and texture file. In jME, I can only assign the entire mesh to a material with one texture file. How do I assign each submesh to a different texture?

2

You have to assign the material to the single Geometries, not to the super node. Open the model in the jMP SceneViewer to see its structure.

[snippet id=“13”]

Cheers,

Normen

3

I did as you said, and each submesh has the correct material, but the UV mapping is wrong for all of them. Am I missing something?



[java] Material guy0 = new Material(assetManager, “Common/MatDefs/Light/Lighting.j3md”);

guy0.setTexture(“m_DiffuseMap”, assetManager.loadTexture(“guy/helmet.png”));

guy0.setFloat(“m_Shininess”, 10);



Material guy1 = new Material(assetManager, “Common/MatDefs/Light/Lighting.j3md”);

guy1.setTexture(“m_DiffuseMap”, assetManager.loadTexture(“guy/shirt.png”));

guy1.setFloat(“m_Shininess”, 20);



Material guy2 = new Material(assetManager, “Common/MatDefs/Light/Lighting.j3md”);

guy2.setTexture(“m_DiffuseMap”, assetManager.loadTexture(“guy/body.png”));

guy2.setFloat(“m_Shininess”, 50);



Material guy3 = new Material(assetManager, “Common/MatDefs/Light/Lighting.j3md”);

guy3.setTexture(“m_DiffuseMap”, assetManager.loadTexture(“guy/shorts.png”));

guy3.setFloat(“m_Shininess”, 20);



Node guy = (Node)assetManager.loadModel(“guy/guy.mesh.xml”);

((Geometry)guy.getChild(0)).setMaterial(guy0);

((Geometry)guy.getChild(1)).setMaterial(guy1);

((Geometry)guy.getChild(2)).setMaterial(guy2);

((Geometry)guy.getChild(3)).setMaterial(guy3);

// guy.setShadowMode(ShadowMode.CastAndReceive);

guy.setLocalScale(.1f);

rootNode.attachChild(guy);[/java]

4

Most likely you need to flip the texture, the OgreXML loader does this by default.

Why aren’t you using the ogre materials, but creating them manually for the ogre mesh?

5

Flipping the textures fixed the UV mapping problem, but I get a weird graphics error. It seems some faces aren’t displayed depending on where the camera is looking - different parts disappear as I pan the camera:







What’s the problem here?



Also, just adding the model makes it bright red. I have to add the textures manually. I’m not sure what “ogre materials” are.

6

Try

[java]TangentBinormalGenerator.generate(geometry.getMesh());[/java]

on the geometrys meshes.



@Momoko_Fan: Shouldnt this be default when there are no tangents?



Cheers,

Normen



P.S. All of this is much easier when using jMP to convert the model before :wink:

7

@Normen: I don’t think so, because OgreXML does not support normal mapping. You need to either create a J3M or manually apply normal mapping in code like is done above.