public override double GetIntersection(Vector from, Vector to, ref Vector normalAtPoint)
{
// static Vector3D IntersectPoint(Vector3D rayVector, Vector3D rayPoint, Vector3D planeNormal, Vector3D planePoint)
//rayVector parameters from to, ray point calculate point , planeNormal..attribute, planePoint .. attribute
//line goes from camera position to one of canvas point, this is from & to vectors
//Line line = new Line(to - from, from);
//Vector p = line.point;
//Vector v = line.direction;
//Vector n = normal;
//double dot1 = Vector.dot(n, v);
//double dot2 = Vector.dot(n, p);
//if (dot1 == 0)
// return 0;
double t = GetIntersection(from, to);
//find intersection point
Vector ret = new Vector();
//ret = p + (t * v);//
ret = to * t + from;
normalAtPoint = normal;//
normalAtPoint = new Vector(ret.X, ret.Y, ret.Z);
normalAtPoint.normalize();
return(t);
}
/// <summary>
/// Unit vector of the vector defined by vector's components
/// </summary>
public Vector unitVector(double x, double y, double z)
{
Vector v = new Vector(x, y, z);
v.normalize();
return(v);
}
public override double GetIntersection(Vector from, Vector to, ref Vector normalAtPoint)
{
Vector u = new Vector(v1 - v0);
Vector v = new Vector(v2 - v0);
Vector n = Vector.CrossProd(u, v);
Vector dir = to - from;
Vector w0 = from - v0;
double a = -1 * Vector.dot(n, w0);
double b = Vector.dot(n, dir);
if (Math.Abs(b) < 0.000000001)
{
if (a == 0)
{
return(2);
}
else
{
return(0);
}
}
double r = a / b;
if (r < 0)
{
return(0);
}
Vector I = from + r * dir;
double uu, uv, vv, wu, wv, D;
uu = Vector.dot(u, u);
uv = Vector.dot(u, v);
vv = Vector.dot(v, v);
Vector w = I - v0;
wu = Vector.dot(w, u);
wv = Vector.dot(w, v);
D = uv * uv - uu * vv;
double s, t;
s = (uv * wv - vv * wu) / D;
if (s < 0.0 || s > 1.0) // neni v trojuhelniku
{
return(0);
}
t = (uv * wu - uu * wv) / D;
if (t < 0.0 || (s + t) > 1.0) // neni v trojuhelniku
{
return(0);
}
normalAtPoint = I;
normalAtPoint.normalize();
return(t); // je v trojuhelniku
//returning point
//V0 + s * u + t * v
//u = V1 - V0
//v = V2 - V0
}
public override double GetIntersection(Vector from, Vector to, ref Vector normalAtPoint)
{
to.normalize();//sphere
double t = GetIntersection(from, to);
Vector v1 = to * t + from;
v1 = v1 - position;
v1.normalize();
normalAtPoint = v1;
return(t);
}
/// <summary>
/// Unit vector of the vector
/// </summary>
public Vector unitVector(Vector v)
{
v.normalize();
return(v);
}