public Tuple ShadeHit(World w, Computation comps, int remaining)
{
Tuple surface = Tuple.Color(0, 0, 0);
foreach (var light in w.Lights)
{
bool shadowed = w.IsShadowed(light, comps.OverPoint);
surface += Lighting(comps.Material,
comps.Object,
light,
comps.Point,
comps.Eyev,
comps.Normalv,
shadowed);
}
Tuple reflected = ReflectedColor(w, comps, remaining);
Tuple refracted = RefractedColor(w, comps, remaining);
Material material = comps.Material;
if (material.Reflective > 0 && material.Transparency > 0)
{
float reflectance = Fresnel.Schlick(comps);
return(surface + reflected * reflectance + refracted * (1 - reflectance));
}
return(surface + reflected + refracted);
}
public override Tuple Lighting(Material m, Shape shape, Light l, Tuple position, Tuple toEye, Tuple normal, bool inShadow)
{
Tuple color = (m.Pattern == null)? m.Color : m.Pattern.ColorAtShape(shape, position);
Tuple effectiveColor = color * l.Intensity;
Tuple toLight = (l.Position - position).Normalize();
Tuple ambient = effectiveColor * m.Ambient;
float ndotl = normal.Dot(toLight);
Tuple diffuse = Tuple.Color(0, 0, 0);
Tuple specular = Tuple.Color(0, 0, 0);
if ((inShadow == false) && (ndotl >= 0))
{
diffuse = effectiveColor * m.Diffuse * ndotl;
Tuple reflect = (-toLight).Reflect(normal);
float rdote = reflect.Dot(toEye);
if (rdote > 0)
{
specular = l.Intensity * m.Specular * Pow(rdote, m.Shininess);
}
}
return(ambient + diffuse + specular);
}
public Tuple RefractedColor(World w, Computation comps, int remaining)
{
if ((remaining <= 0) ||
(Abs(comps.Material.Transparency) < Constants.floatEps))
{
return(Tuple.Color(0, 0, 0));
}
float nRatio = comps.N1 / comps.N2;
float cosTheta_i = comps.Eyev.Dot(comps.Normalv);
float sin2Theta_t = nRatio * nRatio * (1 - cosTheta_i * cosTheta_i);
if (sin2Theta_t >= 1)
{
return(Tuple.Color(0, 0, 0));
}
float cosTheta_t = Sqrt(1 - sin2Theta_t);
Tuple direction = comps.Normalv * (nRatio * cosTheta_i - cosTheta_t) - comps.Eyev * nRatio;
Ray refractRay = new Ray(comps.UnderPoint, direction);
Tuple color = ColorAt(w, refractRay, remaining - 1);
return(color * comps.Material.Transparency);
}
public Material()
{
Color = Tuple.Color(1, 1, 1);
Ambient = 0.1f;
Diffuse = 0.9f;
Specular = 0.9f;
Shininess = 200.0f;
RefractiveIndex = 1;
}
public Tuple ReflectedColor(World w, Computation comps, int remaining)
{
if ((remaining <= 0) ||
(Abs(comps.Material.Reflective) < Constants.floatEps))
{
return(Tuple.Color(0, 0, 0));
}
Ray reflectRay = new Ray(comps.OverPoint, comps.Reflectv);
Tuple color = ColorAt(w, reflectRay, remaining - 1);
return(color * comps.Material.Reflective);
}
public Tuple ColorAt(World w, Ray r, int remaining)
{
List <Intersection> intersections = w.Intersection(r);
Intersection intersection = Intersection.Hit(intersections);
if (intersection == null)
{
return(Tuple.Color(0, 0, 0));
}
Computation comps = new Computation(intersection, r, intersections);
return(ShadeHit(w, comps, remaining));
}
public Canvas(int width, int height)
{
Width = width;
Height = height;
_pixels = new Tuple[Height, Width];
for (int y = 0; y < Height; ++y)
{
for (int x = 0; x < Width; ++x)
{
_pixels[y, x] = Tuple.Color(0, 0, 0);
}
}
}
public DefaultWorld()
{
Lights.Add(new PointLight(Tuple.Point(-10, 10, -10), Tuple.Color(1, 1, 1)));
Shape s1 = new Sphere();
s1.Material.Color = Tuple.Color(0.8f, 1, 0.6f);
s1.Material.Diffuse = 0.7f;
s1.Material.Specular = 0.2f;
Shapes.Add(s1);
Shape s2 = new Sphere();
s2.Transform = Transformation.Scaling(0.5f, 0.5f, 0.5f);
Shapes.Add(s2);
}
private static Tuple ReadColor(JToken jToken)
{
return(Tuple.Color((float)jToken[0], (float)jToken[1], (float)jToken[2]));
}
