What is the best way to detect mouse-location/clicks on object in OpenGL?

Question

I am creating a simple 2D OpenGL game, and I need to know when the player clicks or mouses over an OpenGL primitive. (For example, on a GL_QUADS that serves as one of the tiles...) There doesn't seems to be a simple way to do this beyond brute force or opengl.org's suggestion of using a unique color for every one of my primitives, which seems a little hacky. Am I missing something? Thanks...

Answer 1

My advice, don't use OpenGL's selection mode or OpenGL rendering (brute force method you are talking about), use a CPU-based ray picking algorithm if 3D. For 2D, like in your case, it should be straightforward, it's just a test to know if a 2D point is in a 2D rectangle.