public static double LinePointDist(Line ab, Point c)
{
Point v1 = ab.Start.Vector(ab.End);
Point v2 = ab.End.Vector(c);
double projDistance = Math.Abs(dot(v2, v1) / v1.Magnitude());
double diag = ab.End.Vector(c).Magnitude();
return(Math.Sqrt(diag * diag - projDistance * projDistance));
}
public static double getAngle(Point a, Point b, Point c)
{
if (a.Equals(b) || b.Equals(c))
{
return(10);
}
Point VecB = a.Vector(b);
Point VecC = b.Vector(c);
double ang = Math.Acos(dot(VecB, VecC) / (VecB.Magnitude() * VecC.Magnitude()));
double angB = Math.Atan2(VecB.Y, VecB.X);
double angC = Math.Atan2(VecC.Y, VecC.X);
angB += (angB < 0 ? 2 * Math.PI : 0);
angC += (angC < 0 ? 2 * Math.PI : 0);
if (Math.Abs(angC - angB - ang) > 1e-6)
{
ang = ang - 2;
}
ang = (angC - angB) + ((angC - angB) < 0 ? 2 * Math.PI : 0);
return(ang);
}