public static Vector2d LineIntersectionPoint2d(Line2d l1, Line2d l2)
{
double x1 = l1.u.x, y1 = l1.u.y;
double x2 = l2.u.x, y2 = l2.u.y;
Vector2d d1 = (l1.v - l1.u).normalize();
Vector2d d2 = (l2.v - l2.u).normalize();
double dx = x2 - x1, dy = y2 - y1;
double a1 = d1.x, a2 = d1.y, b1 = d2.x, b2 = d2.y;
double t2 = (dx * a2 - dy * a1) / (a1 * b2 - b1 * a2);
double t1 = 0;
if (a1 != 0)
{
t1 = (dx + b1 * t2) / a1;
}
else
{
t1 = (dy + b2 * t2) / a2;
}
Vector2d vec1 = l1.u + d1 * t1;
Vector2d vec2 = l2.u + d2 * t2;
return(vec1);
}
public static double PointDistToLine(Vector2d pt, Line2d line)
{
Vector2d footPoint = FindPointTolineFootPrint(pt, line);
return((pt - footPoint).Length());
}
