Hi Im a student and just started 3D programming 2 weeks ago. I have this problem:

I got a working collision detection against models created in Maya. But:

The collision is only inside the model, with the normals on the model pointing out as it should be.
If I revers the normals on the model(so you can se inside it but not inside out) the collision works great from the outside.
I don't know if my Maya is configured wrong or if I did wrong, or is it my collision? Any idéa?

The collision is only intersecting the triangles inside for an example a box. Not from the outside...
And I cant have reversed normals on models in the game, it dosent look well.

To mention the collision is against a world. WorldCollision.

Thanks

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Just stating the problem is not enough to help you. Please post your code and algorithms that you are using for the collision detection.

The collision is only inside the model, ...
the normals on the model pointing out as it should be. ...
you can se inside it but not inside out ...
collision works great from the outside. ...
The collision is only intersecting the triangles inside for an example a box. Not from the outside...
To mention the collision is against a world.

These sentences are very confusing, and seemingly self-contradictory. I'm sure it makes sense in your mind, but I certainly can't make heads or tails of it. Please try to explain the issue more clearly.

And I cant have reversed normals on models in the game, it dosent look well.

If what you want is for the faces to appear from both directions, you need to disable "backface culling" (or from gamedev article).

Usually, in 3D modelers like Maya, backface culling is one of the configurations of a material or of the model as a whole. I don't know Maya, so I can't help you.

Heck of a problem, sorry about the sentences. Was not so easy to explain. I found out the problem and it was the collision detection, the debugg object was wrong, and also the model normals were wrong. And I can't post the code, it's sensitive information to bee spread on the internet.

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