Depends on what meshes you are loading. For a .X or .3DS you can use VertexX, VertexY, VertexZ on every vertex. Usually I try to find the maximum/minimum X/Y/Z coordinates. The middle point is the average: (max+min)/2. I never used .B3D, so there might be another way to get its centre position. However, I think it is easiest to create the model around 0, 0, 0 in the editor.
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If I'm correct, models allways rotate around their own (0, 0, 0). In world coordinates that is EntityX(mesh, 1), EntityY(mesh, 1), EntityZ(mesh, 1). Or TFormPoint 0, 0, 0, mesh, 0->then read TFormedX/Y/Z()
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If I'm correct, models allways rotate around their own (0, 0, 0). In world coordinates that is EntityX(mesh, 1), EntityY(mesh, 1), EntityZ(mesh, 1). Or TFormPoint 0, 0, 0, mesh, 0->then read TFormedX/Y/Z()