double geometric(Vector4d s1, Vector4d n1, Vector4d s2, Vector4d n2) {
ASSERT(isUnitVector(n1), "assumes the normals are normalized");
ASSERT(isUnitVector(n2), "assumes the normals are normalized");
Vector4d segment = s1 - s2;
Vector4d seg_dir = segment.normalized();
double cos1 = n1.dot(seg_dir);
double cos2 = n2.dot(-1 * seg_dir);
return std::abs(cos1 * cos2) / segment.squaredNorm();
}
AreaLight::AreaLight(ray orientation, Vector4d up, double size,
int numlights, double brightness) {
this->orientation = orientation;
this->orientation.dir.normalize();
this->up = up.normalized();
right = cross(this->orientation.dir, this->up);
this->size = size;
this->numLights = numlights;
this->brightness = (brightness / numlights / numlights);
}
