The aim of simulation is to produce as real an image of the project as possible but, just as in conventional model-building, it is necessary to simplify the geometrical data. Especially in the case of complex organic objects like trees and plants, the consequences of too much de-tail need to be taken into account. The greater the number of polygons for a specific object, the more time is needed for the process of light calculation.
A model only becomes convincing when material properties are allotted to individual objects. With Autodesk VIZ 4 there is practically no limit to the simulation of all manner of different materials. The problems arise in the computation of the scene. One quickly dis-covers that the finer and more complex the materials selected, the longer the calculations take for each object. So it is a question of find-ing a reasonable compromise between the realism of a scene and the time needed for cal-culation.