public static float Cos(VectorF first, VectorF second)
{
if (first.Length() == 0 || second.Length() == 0)
{
return(0);
}
return(ScalarMultiply(first, second) / (first.Length() * second.Length()));
}
public static PointPosition Classify(VectorF s, VectorF e, VectorF p)
{
VectorF a = e - s;
VectorF b = p - s;
double d = a.X * b.Y - b.X * a.Y;
if (d > 0.0)
{
return(PointPosition.LEFT);
}
if (d < 0.0)
{
return(PointPosition.RIGHT);
}
if ((a.X * b.X < 0.0) || (a.Y * b.Y < 0.0))
{
return(PointPosition.BEHIND);
}
if (a.Length() < b.Length())
{
return(PointPosition.FRONT);
}
if (p == s)
{
return(PointPosition.ORIGIN);
}
if (p == e)
{
return(PointPosition.DESTINATION);
}
return(PointPosition.BETWEEN);
}
