static Point RotatePointAroundPoint(Point, Point, double);
static double Determinant(Point, Point);
static int Intersects(Line *, Line *, double * tp = 0, double * up = 0);
static Point RotatePointAroundPoint(Point, Point, double);
static double Determinant(Point, Point);
static int Intersects(Line *, Line *, double * tp = 0, double * up = 0);