GaussXX

Format

GaussNR,   sigma, GaussNT,   sigma, GaussSR,   sigma, GaussST,   sigma // all float

The probability of a light ray being reflected by or transmitted through the surface according to Gaussian distribution, and the corresponding standard deviation. The central direction of Gaussian distribution can be given by either normal vector or specular vector. "R" stands for reflection and "T" stands for Transmission. "N" stands for normal and "S" stands for specular. The "sigma" values are the standard deviations for corresponding Gaussian distributions.

Math

BSDF	PDF
$Ae^{(\frac{-\sin \theta}{\sigma})^2}$	$Ae^{(\frac{-\sin \theta}{\sigma})^2}\cos \theta$