A camera control interface based on the visualization of subspaces of the 6D motion space of the camera

The paper describes a camera control interface for the exploration of 3D virtual space implemented by using a 2D input device, a joystick. The interface uses a helicopter maneuver metaphor: the viewpoint of the virtual camera is controlled as if the user sits in a helicopter and controls its motion. To control the helicopter by a 2D input device, the 6D space of the helicopter motion is decomposed into six 2D subspaces. The 2D subspaces are visualized by means of the helicopter model and some auxiliary means, e.g. plane meshes and circles, to suggest the kind of motion allowed in each subspace. The visualized subspaces are used as camera control widgets controlled by the 2D input device. The six widgets are arranged so that the transition from one widget to another may be performed by one movement of the input device. This interface provides a simple and consistent kinesthetic correspondence between the movement of the joystick and the motion of the helicopter i.e. the virtual camera. We have conducted an evaluation of our camera control interface through a questionnaire study. Though it indicates that users of different levels find our interface easier to use compared to other interfaces, we need more rigorous evaluation studies to prove it. The main claim of the paper is that the proposed interface has a cleaner and more logical design obtained by strictly following a good design principle, i.e. systematic decomposition and intuitive visual clues.