> Another major system for Trespasser was its audio system, which we described as "real time Foley" because of its ability to generate collision and scraping effects between differing sound materials in real time. Although the system could have used more sound material data, even with what it had it resulted in some wonderfully immersive sound effects which most other games do not duplicate - things like scraping a board down a concrete surface or hitting an oil barrel with a metal bat sound just about perfect. Since the system doesn’t simply play two sound effects but actually chooses from a group of samples and sets volumes based on the underlying physics collision, it sounds much more natural than most other audio systems currently used.