Abstract: Content creation for computer graphics applications is a laborious process that requires skilled personnel. One fundamental problem is that manipulation of 3D objects with 2D user interfaces is very difficult for non-experienced users. In this paper, we introduce a new system that uses constraints to restrict object motion in a 3D scene, making interaction much simpler and more intuitive. We compare three different 3D scene manipulation techniques based on a 2D user interface. We show that the presented techniques are significantly more efficient than commonly used solutions. To our knowledge, this is the first evaluation of 3D manipulation techniques with 2D devices and constraints.