Graphics Reference
In-Depth Information
5
II
TressFX: Advanced Real-Time
Hair Rendering
Timothy Martin, Wolfgang Engel, Nicolas
Thibieroz, Jason Yang, and Jason Lacroix
5.1 Introduction
Hair is one of the key materials in the realm of realistic real-time character ren-
dering that has proven to be a dicult endeavour. The conventional approach
would be to author hair using “fins and shells” or a standard mesh, then use a
combination of textures, noise maps, and anisotropic lighting to produce the ef-
fect of a full head of hair [Scheuermann 04]. In this chapter, we cover a real-time
hair rendering technique that renders hair as individual strands and how that
technique was modified and optimized to integrate into a game and run at peak
performance. (See Figure 5.1.) Hair-specific topics that will be covered include
geometry expansion, antialiasing, lighting, shadows, and the usage of per-pixel
Figure 5.1.
Here is a comparison of hair rendered in
Tomb Raider
using a mesh with a
cloth simulation applied to the ponytail in the left image versus the TressFX advanced
real-time hair rendered as individual strands in the image on the right.
