If I have a sphere that is being rotate by the users mouse, how could I (at any time, say via a button) apply some rotation transformation on the Camera so that a specific spot on the Sphere is facing the User?
Currently I'm implementing a trackball approach that moves the camera around when the user clicks and drags, and I would like to be able to "Pan" to a specific spot on the Sphere, but I dont know how to calculate the required 3D rotation transformation based on the cameras current position.
Any help here would be greatly appreciated.
Thanks, Mark