Describe the concept of Potentially Visible Sets (PVS) and discuss how and why different flavours of PVS might be used in network games.
A Potentially Visible Set (PVS) is a collection of objects in a game world which may be visible from a given location in that world.
- The primary purpose of PVS is to compute the polygons which are visible from a player or object’s point of view. However, to maximise processing efficiency, it is often better to calculate PVS on a per-object as
- opposed to per-polygon basis
PVS may be used in networked games as a component of Area of Interest (AOI) management. As a result of the type of PVS used, latency may occur.
Many games use a conservative PVS approximation, which is the fastest method of PVS, however, it may result in excess rendering and lower frame-rates which can cause latency.
- In slow-paced networked games such as turn-based strategy games, this may not be a huge issue. However in the case of fast-paced, graphically-intensive games such as first-person shooters, a more exact PVS
- algorithm may be used in order to lower rendering times and maximise frame-rates, and in turn, decreasing latency.