/*
====================
R_LightProjectionMatrix
====================
*/
void R_LightProjectionMatrix( const idVec3 &origin, const idPlane &rearPlane, idVec4 mat[4] ) {
idVec4 lv;
float lg;
// calculate the homogenious light vector
lv.x = origin.x;
lv.y = origin.y;
lv.z = origin.z;
lv.w = 1;
lg = rearPlane.ToVec4() * lv;
// outer product
mat[0][0] = lg -rearPlane[0] * lv[0];
mat[0][1] = -rearPlane[1] * lv[0];
mat[0][2] = -rearPlane[2] * lv[0];
mat[0][3] = -rearPlane[3] * lv[0];
mat[1][0] = -rearPlane[0] * lv[1];
mat[1][1] = lg -rearPlane[1] * lv[1];
mat[1][2] = -rearPlane[2] * lv[1];
mat[1][3] = -rearPlane[3] * lv[1];
mat[2][0] = -rearPlane[0] * lv[2];
mat[2][1] = -rearPlane[1] * lv[2];
mat[2][2] = lg -rearPlane[2] * lv[2];
mat[2][3] = -rearPlane[3] * lv[2];
mat[3][0] = -rearPlane[0] * lv[3];
mat[3][1] = -rearPlane[1] * lv[3];
mat[3][2] = -rearPlane[2] * lv[3];
mat[3][3] = lg -rearPlane[3] * lv[3];
}
