title: How do I implement basic camera operations in OpenGL?
body: <p>I'm trying to implement an application using OpenGL and I need to implement the basic camera movements: orbit, pan and zoom. </p>
  
  <p>To make it a little clearer, I need Maya-like camera control. Due to the nature of the application, I can't use the good ol' "transform the scene to make it look like the camera moves". So I'm stuck using transform matrices, gluLookAt, and such. </p>
  
  <p>Zoom I know is dead easy, I just have to hook to the depth component of the eye vector (gluLookAt), but I'm not quite sure how to implement the other two, pan and orbit. Has anyone ever done this?</p>