80 lines
2.1 KiB
C++
Executable File
80 lines
2.1 KiB
C++
Executable File
//----------------------------------------------------------------
|
|
//
|
|
// Name: SHCoeffs.h
|
|
// Last Update: 25/11/03
|
|
// Author: Rich Cross
|
|
// Contact: rich@0ad.wildfiregames.com
|
|
//
|
|
// Description: implementation of 9 component spherical harmonic
|
|
// lighting
|
|
//----------------------------------------------------------------
|
|
|
|
#include "precompiled.h"
|
|
|
|
#include "SHCoeffs.h"
|
|
|
|
CSHCoeffs::CSHCoeffs()
|
|
{
|
|
Clear();
|
|
}
|
|
|
|
void CSHCoeffs::Clear()
|
|
{
|
|
for (int i=0;i<9;i++) {
|
|
_data[i].Clear();
|
|
}
|
|
}
|
|
|
|
void CSHCoeffs::AddAmbientLight(const RGBColor& color)
|
|
{
|
|
_data[0]+=color;
|
|
}
|
|
|
|
void CSHCoeffs::AddDirectionalLight(const CVector3D& lightDir,const RGBColor& lightColor)
|
|
{
|
|
CVector3D dirToLight(-lightDir.X,-lightDir.Y,-lightDir.Z);
|
|
|
|
const float normalisation = PI*16/17;
|
|
const float c1 = SQR(0.282095f) * normalisation * 1.0f;
|
|
const float c2 = SQR(0.488603f) * normalisation * (2.0f/3.0f);
|
|
const float c3 = SQR(1.092548f) * normalisation * (1.0f/4.0f);
|
|
const float c4 = SQR(0.315392f) * normalisation * (1.0f/4.0f);
|
|
const float c5 = SQR(0.546274f) * normalisation * (1.0f/4.0f);
|
|
|
|
_data[0]+=lightColor*c1;
|
|
_data[1]+=lightColor*c2*dirToLight.X;
|
|
_data[2]+=lightColor*c2*dirToLight.Y;
|
|
_data[3]+=lightColor*c2*dirToLight.Z;
|
|
_data[4]+=lightColor*c3*dirToLight.X*dirToLight.Z;
|
|
_data[5]+=lightColor*c3*dirToLight.Z*dirToLight.Y;
|
|
_data[6]+=lightColor*c3*dirToLight.Y*dirToLight.X;
|
|
_data[7]+=lightColor*c4*(3.0f*SQR(dirToLight.Z)-1.0f);
|
|
_data[8]+=lightColor*c5*(SQR(dirToLight.X)-SQR(dirToLight.Y));
|
|
}
|
|
|
|
void CSHCoeffs::Evaluate(const CVector3D& normal,RGBColor& color) const
|
|
{
|
|
#if 1
|
|
float c4=normal.X*normal.Z;
|
|
float c5=normal.Z*normal.Y;
|
|
float c6=normal.Y*normal.X;
|
|
float c7=(3*SQR(normal.Z)-1.0f);
|
|
float c8=(SQR(normal.X)-SQR(normal.Y));
|
|
|
|
for (int i=0;i<3;i++) {
|
|
color[i]=_data[0][i];
|
|
color[i]+=_data[1][i]*normal.X;
|
|
color[i]+=_data[2][i]*normal.Y;
|
|
color[i]+=_data[3][i]*normal.Z;
|
|
color[i]+=_data[4][i]*c4;
|
|
color[i]+=_data[5][i]*c5;
|
|
color[i]+=_data[6][i]*c6;
|
|
color[i]+=_data[7][i]*c7;
|
|
color[i]+=_data[8][i]*c8;
|
|
}
|
|
#else
|
|
// debug aid: output quantised normal
|
|
color=RGBColor((normal.X+1)*0.5,(normal.Y+1)*0.5,(normal.Z+1)*0.5);
|
|
#endif
|
|
}
|