private IntersectInfo IntersectSlab(Ray ray, Vector P1, Vector P2, Vector P3)
{
Vector N = (P1 - P3).Cross(P2 - P3).Normalize();
double d = N.Dot(P1);
IntersectInfo info = new IntersectInfo();
double Vd = N.Dot(ray.Direction);
if (Vd == 0)
{
return(info); // no intersection
}
double t = -(N.Dot(ray.Position) - d) / Vd;
if (t <= 0)
{
return(info);
}
Vector hit = ray.Position + ray.Direction * t;
if ((hit.x < P1.x || hit.x > P2.x) && (P1.x != P2.x))
{
return(info);
}
if ((hit.y < P3.y || hit.y > P1.y) && (P1.y != P2.y))
{
return(info);
}
//if ((hit.z < P1.z || hit.z > P3.z) && (P1.z != P3.z)) return info;
if ((hit.z < P1.z || hit.z > P2.z) && (P1.z != P2.z))
{
return(info);
}
info.Element = this;
info.IsHit = true;
info.Position = hit;
info.Normal = N;// *-1;
info.Distance = t;
if (Material.HasTexture)
{
//Vector vecU = new Vector(hit.y - Position.y, hit.z - Position.z, Position.x-hit.x);
Vector vecU = new Vector((P1.y + P2.y) / 2 - Position.y, (P1.z + P2.z) / 2 - Position.z, Position.x - (P1.x + P2.x) / 2).Normalize();
Vector vecV = vecU.Cross((P1 + P2) / 2 - Position).Normalize();
double u = info.Position.Dot(vecU);
double v = info.Position.Dot(vecV);
info.Color = Material.GetColor(u, v);
}
else
{
info.Color = Material.GetColor(0, 0);
}
return(info);
}
/// <summary>
/// Metoda LookAt
/// Umoznuje nastaveni kamery na zadanou polohu a uhel pohledu
/// </summary>
/// <param name="eye">Vector umisteni kamery</param>
/// <param name="focus">Vector s bodem lomu</param>
/// <param name="aspect">aspect</param>
/// <param name="fovY">Uhel pohledu</param>
/// <returns></returns>
public static Camera LookAt(Vector eye, Vector focus, double aspect, double fovY)
{
double zoom = 1.0 / Math.Tan((fovY * 0.5) * (Math.PI / 180.0));
Vector forward = (focus - eye).Normalized * zoom;
Vector right = forward.Cross(GlobalUp).Normalized *aspect;
Vector up = right.Cross(forward).Normalized;
return(new Camera(eye, forward, right, up, fovY));
}
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
});
}
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)));
//Console.WriteLine($"eye {pos.X} {pos.Y} {pos.Z}");
//Console.WriteLine($"lookAt {lookAt.X} {lookAt.Y} {lookAt.Z}");
//Console.WriteLine($"up {up.X} {up.Y} {up.Z}");
return(new Camera()
{
Pos = pos, Forward = forward, Up = up, Right = right
});
}
public override IntersectInfo Intersect(Ray ray)
{
IntersectInfo info = new IntersectInfo();
double Vd = Position.Dot(ray.Direction);
if (Vd == 0)
{
return(info); // no intersection
}
double t = -(Position.Dot(ray.Position) + D) / Vd;
if (t <= 0)
{
return(info);
}
info.Element = this;
info.IsHit = true;
info.Position = ray.Position + ray.Direction * t;
info.Normal = Position;// *-1;
info.Distance = t;
if (Material.HasTexture)
{
Vector vecU = new Vector(Position.y, Position.z, -Position.x);
Vector vecV = vecU.Cross(Position);
double u = info.Position.Dot(vecU);
double v = info.Position.Dot(vecV);
info.Color = Material.GetColor(u, v);
}
else
{
info.Color = Material.GetColor(0, 0);
}
return(info);
}