Light Scattering from Human Hair Fibers
Henrik Wann Jensen,
University of Californa, San Diego
To appear in Siggraph 2003
Light scattering from hair is normally simulated in computer graphics
using Kajiya and Kayís classic phenomenological model. We
have made new measurements that exhibit visually significant effects
not predicted by Kajiya and Kayís model. Our measurements
go beyond previous hair measurements by examining out-of-plane
scattering, and together with this previous work they show a multiple
specular highlight and variation in scattering with rotation about
the fiber axis. We explain the sources of these effects using a model
of a hair fiber as a transparent elliptical cylinder with an absorbing
interior and a surface covered with tilted scales. Based on an analytical
scattering function for a circular cylinder, we propose a practical
shading model for hair that qualitatively matches the scattering
behavior shown in the measurements. In a comparison between a
photograph and rendered images, we demonstrate the new modelís
ability to match the appearance of real hair.
This page created by Mike
Cammarano, Mon 27 Jan 2003, copied by Steve Marschner 3 Feb 2003.
Last modified: Mon 28 Apr 2003.