Visualisation of impact of time on the internal lighting of a building

The visualisation of an object, such as a building, 'in time'-viewing it from different perspectives-has been the subject of many research and development efforts, and significant inroads have been made in this area, which is supported by a sophisticated software technology. On the other hand, visualisation of a building 'though time'-viewing it as it ages or gets younger-has received little attention. In a previous publication by the authors (Proc. Int. Conf. on Inform. Visualisation, London, England, 27-29 Aug. 1997), this concept was introduced and applied to the building maintenance programme. The overall process was modelled and generalised, and lighting, paints and carpets were introduced as examples where the research work can be applied. This paper concentrates on the lighting system and determines the time-related behaviour of different light sources under the impact of intrinsic and environmental factors. This process is modelled and expressed in a mathematical form which facilitates its visualisation through the use of VRML.