Original Post
Hello! To make this simple, I need a method of reverting screen coords into world coords. That is, given a point on the screen, I need to have the origin and direction for a ray cast from that point in the camera. This ray should counter the perspective correction so that it would only look like a dot on-screen, like this, you could effectively trace the ray's first collision with a mesh. Using this method you could, given a point on the screen, retrieve the exact point in the 3D-world that is visible at this screen coordinate (if depth testing is enabled). I know enough about picking and all, and I know how to use the matrices to determine where a point in the world will end up on the screen. I am *thinking* this might be done by using the inverted perspective matrix in some kind of magic way, but if anyone has some pointers before I start the old "trial-and-error-and-google" routine, it'd be great!