•To date, used mostly to speed up
rendering by eliminating the drawing of things hidden behind walls, floors or
•Takes a while to create, but the process can be totally automated
by beam tracing.
•Can be stored as BSP trees or trees ofhiearchal bounding boxes.
precise PVS can be a lot of data.
an imprecise PVS works nearly as well and is a LOT smaller and easier to do.