If it is set to immobile, the object's collision will not work correctly. The model MUST be made of triangular faces, directX uses tris, so modelling it with non-tris polygons will cause this.
Here is a code that could help you to understand DX modelling a bit better.
[] = bad
[\]= good
Turn the single face, 4 sided square into two 3-sided triangles.
More than 4 sided polygons are just known as polygons, will
appear, but have collision problems.
4 sided polygons are called Quads, will appear, but have
collision problems.
3 sided polygons are called Tris, will work normally on dynamic
or static.
hope this helps
thanks
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