I am making a game that is partially 3D, with six 2D layouts. In my 3d layout, I have a cube. Each side is supposed to be linked to a 2D layout, so that when you click on a face of the cube, it sends you to the corresponding 2d layout. I cannot figure out how to do this. If I new how to calculate a line from the camera to the mouse, I could cast a sprite in that direction and check for collision; however, I do not know how to do this. Any new ideas and information are very greatly appreciated, for I have searched and searched for a solution and do not have time to search anymore. Thanks in advance for any help given.