Scattering-based interactive hair rendering

Simulating fast and realistic complex light effect within hair is one of the most challenging problems in the field of virtual humans, both in terms of research and of development. In this paper we propose a scattering-based fast and efficient algorithm that handles both the local specular highlights and global self-shadow in animated hair at interactive rates. We introduce a fast refinement technique for incorporating illumination variations in animated hair from the encoded hair density changes considering the spatial coherency in hair data. Our method does pre-computations for any static hairstyle, optimizes it and then efficiently utilizes it along with the refined data for the animated hairstyle. The various optimizations implemented result in interactive simulation while maintaining the aesthetic visual appearance of the hair.

1. Introduction

Hair rendering is one of the important requirements for achieving believable virtual humans and despite considerable success it still is a challenging task and requires special effort. Currently, to have an efficient and a fast rendering approach, in particular to develop a real-time system is one of the primary motivating factors in this research.