1. Introduction
Cyberworlds within the cyberspace can be considered as entities where information modelling can be undertaken through the integration of both spatial and temporal models. There is no doubt that visualisation within cyberworlds is an important aspect which requires special attention. As the gap between the cyberworlds and the real world gets narrower, the demand placed for realism within these shared virtual worlds, both in terms of the complexity of geometric models as well as their appearance, is ever increasing.