A framework for interactive GPU-supported rendering and styling of virtual hair

The interactive styling and rendering of virtual hair is essential for creating realistic looking human avatars for use in computer games, virtual worlds, and movie special effects. Hair models can contain tens of thousands of hair strands and hence it is important to develop techniques to modify the hair in a realistic fashion and to render it at interactive frame rates. In this paper we present a GPU-based framework for styling and rendering of virtual hair. We use wisps to represent basic units of hair strands and present an improved statistical model for hair wisp generation which allows the creation of smooth and fringy styles. Fast modelling is achieved by using create, edit, delete and copy and paste operations for key strands representing wisp. The styling process is simplified by using a local coordinate system for hair strands in order to define preferred styling (brushing) directions. Fast photo-realistic rendering is achieved by using the latest GPU functionalities for both the light reflection calculation and the shadow generation of hair strands. We also propose a new method for real-time anti-aliasing using GPU programming.