Vector_3D<double> Sphere::
Normal(const Vector_3D<double>& location) const
{
Vector_3D<double> normal;
normal = (location - center);
normal.Normalize();
return normal;
}
Vector_3D<double> Sphere::
Normal(const Vector_3D<double>& location) const
{
Vector_3D<double> normal;
normal.x = (location.x - center.x);
normal.y = (location.y - center.y);
normal.z = (location.z - center.z);
normal.Normalize();
return normal;
}
//--------------------------------------------------------------------------------
// Shader
//--------------------------------------------------------------------------------
Vector_3D<double> Phong_Shader::
Shade_Surface(const Ray& ray,const Object& intersection_object,const Vector_3D<double>& intersection_point,const Vector_3D<double>& same_side_normal) const
{
Vector_3D<double> color;
Vector_3D<double> ambientCoefficient = color_ambient;
Vector_3D<double> diffuseReflectance = color_diffuse;
// TODO: determine the color
//compute each R G B value seperately
//ambient
ambientCoefficient.x *= world.lights.at(0)->Emitted_Light(ray).x;
ambientCoefficient.y *= world.lights.at(0)->Emitted_Light(ray).y;
ambientCoefficient.z *= world.lights.at(0)->Emitted_Light(ray).z;
color += ambientCoefficient;
for (unsigned i = 0; i < world.lights.size(); ++i)
{
//test for shadows
Vector_3D<double> lightVector = (((world.lights.at(i))->position)-intersection_point);
//tempray
Ray tempRay;
tempRay.endpoint = intersection_point;
tempRay.direction = lightVector;
tempRay.direction.Normalize();
tempRay.t_max = 999999;
tempRay.semi_infinite = true;
bool shadowDetected = false;
for (unsigned j = 0; j < world.objects.size(); ++j)
{
////calculate if object intersects
if (world.objects.at(j)->Intersection(tempRay))
{
if (!(tempRay.current_object == &intersection_object))
{
shadowDetected = true;
}
}
}
if (!(world.enable_shadows && shadowDetected))
{
Vector_3D<double> normal = intersection_object.Normal(intersection_point);
//diffuse shading
Vector_3D<double> diffuseIntensity = world.lights.at(i)->Emitted_Light(ray);
lightVector.Normalize();
double dotProduct = lightVector.x*normal.x + lightVector.y*normal.y + lightVector.z*normal.z;
if (dotProduct < 0)
{
dotProduct = 0;
}
// cout << "RED DIFFUSE INTENSITY: " << diffuseReflectance.x*(diffuseIntensity) << endl;
color.x += dotProduct*diffuseReflectance.x*(diffuseIntensity.x);
color.y += dotProduct*diffuseReflectance.y*(diffuseIntensity.y);
color.z += dotProduct*diffuseReflectance.z*(diffuseIntensity.z);
//specular shading
Vector_3D<double> eyeVector = ray.endpoint - intersection_point;
eyeVector.Normalize();
Vector_3D<double> tempH = lightVector+eyeVector;
tempH.Normalize();
double max = (tempH.x*same_side_normal.x+tempH.y*same_side_normal.y+tempH.z*same_side_normal.z);
if (max < 0)
{
max = 0;
}
color.x += color_specular.x*(world.lights.at(i)->Emitted_Light(ray).x)*pow(max,specular_power);
color.y += color_specular.y*(world.lights.at(i)->Emitted_Light(ray).y)*pow(max,specular_power);
color.z += color_specular.z*(world.lights.at(i)->Emitted_Light(ray).z)*pow(max,specular_power);
}
}
return color;
}
