mingzailao
/
mitsuba
mirror of https://github.com/Quartenia/mitsuba.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Rayleigh phase function bugfix contributed by Nathan Reed

metadata
Wenzel Jakob 2014-05-21 10:57:08 +02:00
parent a82576ffef
commit e53c4afea6
1 changed files with 8 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
src/phase/rayleigh.cpp
View File

@ -23,6 +23,12 @@
MTS_NAMESPACE_BEGIN MTS_NAMESPACE_BEGIN
inline Float cuberoot(Float x) {
return (x < 0.0f) ?
-pow(-x, (Float) (1.0f/3.0f)) :
pow(x, (Float) (1.0f/3.0f));
}
/*!\plugin{rayleigh}{Rayleigh phase function} /*!\plugin{rayleigh}{Rayleigh phase function}
* \order{3} * \order{3}
* *
@ -54,8 +60,8 @@ public:
Float z = 2 * (2*sample.x - 1), Float z = 2 * (2*sample.x - 1),
tmp = std::sqrt(z*z+1), tmp = std::sqrt(z*z+1),
A = std::pow(z+tmp, (Float) (1.0f/3.0f)), A = cuberoot(z+tmp),
B = std::pow(z-tmp, (Float) (1.0f/3.0f)), B = cuberoot(z-tmp),
cosTheta = A + B, cosTheta = A + B,
sinTheta = math::safe_sqrt(1.0f-cosTheta*cosTheta), sinTheta = math::safe_sqrt(1.0f-cosTheta*cosTheta),
phi = 2*M_PI*sample.y, phi = 2*M_PI*sample.y,