public static Segment IntersectCircleLine(Circle circle, Line line)
{
var H = circle.center.ProjectToLine(line);
if (!circle.ContainsPoint(H))
{
return(null);
}
Point v = line.Direction.SetLength(1);
double h = (circle.center - H).Length;
double d = Math.Sqrt(circle.radius * circle.radius - h * h);
return(new Segment(H + v * d, H - v * d));
}
