A Fast and Accurate Light Reflection Model
		Physical Parameters
		Specular component

Components of the BRDF

The BRDF can be divided into three components:

ρbd = ρbd,sp + ρbd,dd + ρbd,ud

(3)

where ρ_bd,sp gives the specular component, ρ_bd,dd gives the directional diffuse component, and ρ_bd,ud gives the uniform diffuse component. The components are shown schematically in Figure 5.

 
Figure 5: Components of the BRDF

We would like to examine the reflected radiance dI_r, which can be expressed as a product of the BRDF and the incident energy flux:

dIr	=	ρbd • dEi
	=	(ρbd,sp + ρbd,dd + ρbd,ud) • dEi
	=	dIr,sp + dIr,dd + dIr,ud	(4)

The general light reflection model that we will use [HE91] assumes a Gaussian, isotropic rough surface. The model is based on wave optics and accounts for diffraction and scattering effects. The model provides closed-form analytic expressions for the specular, directional diffuse, and uniform diffuse components of the BRDF. Any equations not given here are available in [HE91].

• Specular component
• Directional diffuse component
• Uniform diffuse component

Last modified: Mon Sep 5 22:08:04 EDT 2011