I need to do this: I have got a sphere traveling on the screen. I just want that, when a user clicks it, it (not really important) changes color. I just tried to use the HotSpot system that Brian Tischler used on his Particle Sim project, but all the coords for the hot spots are a way hard to find (and by now i don''t know how to do that!! ) I didn''t found any tuts explaining this, so I''m posting up in this borad. I hope someone will please answer me! Magic

Ok, know practically nothing about 3d-programming (yet), but maybe you can have a small object following the mouse, and then make some collision code. You could also try making an invisible 2D layer, with a circle that follows the sphere. In that way, the user will actually hit the circle, not the sphere.

/Niskala

Thanx for your help but I was just reading in the OpenGL SuperBible of a method to do what i was looking for just with an OpenGL native Selection Buffer

Thanx anyway

Magic