public static Vector Times(double n, Vector v)
{
return new Vector(v.X*n, v.Y*n, v.Z*n);
}
public static Vector Norm(Vector v)
{
double mag = Mag(v);
double div = mag == 0 ? double.PositiveInfinity : 1/mag;
return Times(div, v);
}
public static Vector Plus(Vector v1, Vector v2)
{
return new Vector(v1.X + v2.X, v1.Y + v2.Y, v1.Z + v2.Z);
}
public static double Mag(Vector v)
{
return Math.Sqrt(Dot(v, v));
}
public static Vector Minus(Vector v1, Vector v2)
{
return new Vector(v1.X - v2.X, v1.Y - v2.Y, v1.Z - v2.Z);
}
public static double Dot(Vector v1, Vector v2)
{
return (v1.X*v2.X) + (v1.Y*v2.Y) + (v1.Z*v2.Z);
}
public static bool Equals(Vector v1, Vector v2)
{
return (v1.X == v2.X) && (v1.Y == v2.Y) && (v1.Z == v2.Z);
}
public override Vector Normal(Vector pos)
{
return Vector.Norm(Vector.Minus(pos, this.Center));
}
public static Vector Cross(Vector v1, Vector v2)
{
return new Vector(((v1.Y*v2.Z) - (v1.Z*v2.Y)),
((v1.Z*v2.X) - (v1.X*v2.Z)),
((v1.X*v2.Y) - (v1.Y*v2.X)));
}
public abstract Vector Normal(Vector pos);
public override Vector Normal(Vector pos)
{
return this.Norm;
}
public static Camera Create(Vector pos, Vector lookAt)
{
Vector forward = Vector.Norm(Vector.Minus(lookAt, pos));
Vector down = new Vector(0, -1, 0);
Vector right = Vector.Times(1.5, Vector.Norm(Vector.Cross(forward, down)));
Vector up = Vector.Times(1.5, Vector.Norm(Vector.Cross(forward, right)));
return new Camera {Pos = pos, Forward = forward, Up = up, Right = right};
}
private Color GetReflectionColor(SceneObject thing, Vector pos, Vector norm, Vector rd, Scene scene, int depth)
{
return Color.Times(thing.Surface.Reflect(pos), this.TraceRay(new Ray {Start = pos, Dir = rd}, scene, depth + 1));
}
private static Color GetNaturalColor(SceneObject thing, Vector pos, Vector norm, Vector rd, Scene scene)
{
Color ret = Color.Make(0, 0, 0);
foreach (Light light in scene.Lights)
{
Vector ldis = Vector.Minus(light.Pos, pos);
Vector livec = Vector.Norm(ldis);
double neatIsect = TestRay(new Ray {Start = pos, Dir = livec}, scene);
bool isInShadow = !((neatIsect > Vector.Mag(ldis)) || (neatIsect == 0));
if (!isInShadow)
{
double illum = Vector.Dot(livec, norm);
Color lcolor = illum > 0 ? Color.Times(illum, light.Color) : Color.Make(0, 0, 0);
double specular = Vector.Dot(livec, Vector.Norm(rd));
Color scolor = specular > 0 ? Color.Times(Math.Pow(specular, thing.Surface.Roughness), light.Color) : Color.Make(0, 0, 0);
ret = Color.Plus(ret, Color.Plus(Color.Times(thing.Surface.Diffuse(pos), lcolor),
Color.Times(thing.Surface.Specular(pos), scolor)));
}
}
return ret;
}