SceneCollisions & Face Attributes

[Spek]

Not sure what I'm doing wrong here... how to get a Face Attribute from a CollisionTree?

In the past, I just called:

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contactPoint := NewtonContactJointGetFirstContact( contact );
...
contactMaterial := NewtonContactGetMaterial( contactPoint );
faceAttribute   := NewtonMaterialGetContactFaceAttribute( contactMaterial );


And while creating the collisionTree, the "addFace" command would get numbers (pointers actually, thus big numbers). But now the "faceAttibute" is always 0.


I *think* it has to do with using NewtonSceneCollisionXXX functions. Before, I had a separate body
with its own CollisionTree for each part (say Room) of the world. Now there is just 1 body for the
entire world, and rooms are added as follow:

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            nCollisionScene := NewtonBodyGetCollision( nSceneBody );
            NewtonSceneCollisionBeginAddRemove( nCollisionScene );
           
            NewtonCollision tempRoomCollision := makeRoomCollision(); <--- produces tree, adds faces
            nodePtr := NewtonSceneCollisionAddSubCollision( nCollisionScene, roomCollision );
           
            NewtonDestroyCollision( tempRoomCollision );


The collisions and everything just works, but as said, I can't get the FaceAttribute. Nor the
userData I attached to that "tempRoomCollision" object with
tempRoomCollision := NewtonCreateTreeCollision( ..., myStuff ); or
NewtonCollisionSetUserData( tempRoomCollision, myStuff );

I don't really have to know the exact Face ID. Just a custom pointer per subnode is enough.

[Spek]

Excuses, had a bug on my side that prevented me from finding the nCollision owner via:

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contactMaterial := NewtonContactGetMaterial( contactPoint );
...
NewtonCollision colShape := NewtonMaterialGetBodyCollidingShape( contactMaterial, nBodyWorld  );
myStuff := NewtonCollisionGetUserData( colShape  );


So, the issue is solved. Yet I wonder what "NewtonMaterialGetContactFaceAttribute" is supposed to return then. In my case its always 0, while I definitely define a number via "NewtonTreeCollisionAddFace( ...., int(myStuff) );"

In my case I don't really need per-polygon info, but just in case I would... how to get that information?