ABSTRACT
The video games industry has benefited immensely from the wealth of information on instanced rendering and crowd simulation to have emerged in recent years [Dudash 07]. It has allowed developers to create a much more immersive gaming experience with hoards of visible characters that render at interactive frame rates. However, while these techniques form the basis of efficient crowd rendering within a stadium environment, they often fail to realize the unique set of problems and optimization opportunities that exist within this field. This chapter aims to extend on previous work in the field of crowd rendering, focusing predominantly on the math, techniques, and optimizations that can be made for stadium crowds.
3.1 Introduction Many sports titles feature stadia that require some degree of crowd rendering technology. The geometric detail required for both the seats and the crowd characters is a problem on current commercial consoles, especially when trying to reproduce an 80,000-seat stadium. This is made more difficult by the fact that stadium crowds are a peripheral feature that we want to spend as little time on as possible. Indeed, many video games end up having to go with a simple solution, prerendered flip book animations. These generally suffer from inconsistent lighting and a flat overall appearance. Instanced crowd simulation provides the basis for a system that is not only visually much better but is also able to react to in-game events, which can greatly enhance the game play experience. However, even some of the latest games that use this technique suffer from perspective issues and completeness problems. This can lead to whole sections of the crowd being incorrectly oriented at times or undesirable gaps appearing when viewing them from certain angles, both of which can detract from the realism of the experience.
