I have never used D3DXIntersect(); it is typically better to do this manually.

Print debug information related to the world location of the object, the world location of the ray (and its direction), and the final ray position/direction after transforming it by the inverse of the world.

Really, from here out it is just a matter of debugging, which means you are on your own. You will have to learn how to debug.


L. Spiro