You can do it all kinds of ways. Artists don't do it, tools do. Example: Racing game, since cars can't go off the track, you divide the track into segments (a

You can do it all kinds of ways. Artists don't do it, tools do. Example: Racing game, since cars can't go off the track, you divide the track into segments (a few meters long) and compute the PVS for each segment. Plenty of others.