
318 Virtual Reality: Concepts and Technologies
Figure 14.6 Construction of a quadtree from a regular mesh of a two-dimensional space (in this
example, we have modelled the free space, i.e. the complement of the objects)
maximum limit is fixed on the subdivision so that the algorithm can end. Figure 14.6
shows an example of calculating a quadtree on the basis of an image (which itself is a
regular mesh of the space in two dimensions). The passage in a space of dimension 3
is equally obvious.
There are other more elaborate techniques of subdivision which do not divide
the cells as per the axes, but as per simple schemas; these techniques are useful