Hi all, i''ve problems to realize a BoundingBox collision detection in my application at the point of horizontal rotation. I''ve implemented a collision detection where i map the 3d coords of the BoundingBox to 2d coords with gluProject. These coords i check up with the mouse coords and show a 2d-text on the screen for object identification during collision. All works realy fine. The problem is, that this check fails when i realize a x-Axis rotation (y-Axis rotation works fine) by mouse rotation. In this case i got an correct inverse object movement, but the mapping of the mouse coords is identical to the mouse movement (Mouse up -> Box up but Object down !)... I don''t know why this S!@t is happend. Knows anyone a solution or can tell my what i do wrong? Thx 4 any help Christian