The Image based model provides a solution to the problem of scene complexity in 3D modelling. Changing detail level is difficult for polygon objects, but can be easily implemented using multiple resolution images. Reducing detail level on moving through the scene is an easy way for enhanciong performance. Playback method supports most hardware platforms and doesn´t require expensive hardware devices. Limitations are that the scene has to be static and that movement is restricted to defined paths and viewpoints.
For motions like opening a door at a HotSpot in a room interframe-compression can be used , because of the locality of the occurence of the trigger event. A solution for implementing time-variance can be a static background using environment maps and tim-variant objects using 3D rendering. Move freely in a scene is the most challenging part of future design aspects. One solution, with respect to future performance gains, could be the definition of a 3D-grid and run-time interpolation for the current viewpoint. Immersive stereo combined with 3D sound may enhance the experience of navigation.
4. How's Quicktime implemented