Two approaches to the design of lighting systems have developed over the years, embodied in the respective roles of the lighting designer and the illuminating engineer. The illuminating engineer relies on lookup tables and calculations to make lighting decisions, emphasizing the importance of light level over most other considerations. The lighting designer, in contrast, is guided by experience and aesthetic sense to illuminate environments in a way pleasing to the eye. For the illuminating engneer, the current revolution in computer technology has brought accurate illuminance predictions for simple spaces, making selection more reliable and, some would argue, easier. However, the computer revolution has done little to assist the lighting designer, whose evaluation more often depends on visual qualities than on numerical quantities.
The emerging field of visualization in computer science combines calculations with computer graphics to bring another dimension of understanding to scientists, engineers, and designers. This new development holds particular promise for lighting systems design, which is both a numerical and a visual endeavor Rather than being restricted as an engineer to a lighting decision based on a table of illuminance values, or as a designer relying only on experience, one could refer to a computer simulation that predicts quantity and displays quality.