GPU techniques for creating visually diverse crowds in real-time

Real-time crowds significantly improve the realism of virtual environments, therefore their use has increased considerably over the last few years in a variety of applications, including real-time games and virtual tourism. However, due to current hardware limitations, crowd variety tends to be sacrificed in order for the crowd simulation to execute in real-time, which decreases the quality and realism of the crowd.

Currently the little variety that is incorporated in real-time crowds tends to be applied by modulating each avatar with random colours, which has a detrimental effect on the texture quality. Furthermore, the existing crowd variety is often hard to define and control. To overcome these problems a set of techniques are presented, which defines and controls crowd variety, to further improve on current variety and quality of crowds. These techniques permit variety to be introduced: by changing the body mass via the application of a displacement map onto the mesh; by scaling the skeleton of the avatar; by applying HSV colour shifts to different parts of the avatar; and by transferring textures between avatar models. The appearance of the avatars under animation is also improved via the use of muscle displacement within the mesh. With the new techniques, the visual quality of the crowd is improved due to the increase in diversity.