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This might be a bug or it might be user error...

neither a bug nor a user error.

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left to right = -x to x

back to front = -y to y

bottom to top = -z to z

This coordinate system is correct for terrain export. As this is the most "natural" way of aligning the axes for a terrain, I used them throughout the export interface.

For 3D rendering in TC I'm using a different system. The y and z axes have to be exchanged, so y is pointing up. Whenever I display coordinates inside TC I display z as y and y as z (in correspondance to the "natural" coordinate system).

So why.

There are several ways for describing a coordinate system.

- First, one has to choose in which direction the up axis is pointing. There are two common ways of doing it. Either the y axis or the z axis is pointing up.

- Second, one has to chose how the 3 axes of a coodinate system are orientated. Left or right handed.

The commonly mathematically accepted way for these two parameters is right handed with z pointing up. That's the way how most modelling softwares and many graphic engines (OGRE for example) are using it. Unfortunately MS used for DX by default a left handed coordinate system with the y axis pointing up.

That's the problem you are facing. The rotation parameter, which you can set in the object manager, can help you solving the y or z is up problem. For the left or right handed coordinate system problem, one has to filp all vertices at a plane through the x/z axes. Currently I don't have a built in solution for this.

Many exporters have an option for left/right handed export. Maybe you can set this option to left handed, when you export into .obj. You will of course have to use a left handed object set within TC and a right handed within OGRE. Its some extra work, but possible.

It would also be possible for me to do this flipping within the main program by inverting one axis of the object placement's transformation matrix. But this will change the matrix from left to right handed. haven't done this before, don't know if it has any side effect. I'll try. If it works, you will have an additional option within the object manager, with which you can flip the objects.