You have an account on AiGameDev.com, but it looks like you have not yet signed up as an INSIDER (free). It’s a one click process, see below:
Earlier this year at the GDC 2009, the Technical Director at Guerrilla Games Michiel van der Leeuw presented a case study of Killzone 2 entitled “The PlayStation®3's SPUs in the Real World”. A section of Michiel's talk focused on AI and three topics in particular: cover maps, threat prediction and line of sights. This is the first of three articles that digs into the AI technology he discussed.
This part of the coverage looks into cover maps, in particular how they can be used to optimize raycasts — which are often the most expensive AI operation. Below you'll find in-game screenshots, example cover maps, and a transcript of the relevant part of the presentation. The juicy bits include the representation of the cover maps, compression, and how they are used in parallel in the PS3's multi-core environment.