//丟入牆壁起末點
public void Add_New_Wall(PointF p1,PointF p2)
{
Wall new_wall = new Wall();
new_wall.start.X = p1.X;
new_wall.start.Y = p1.Y;
new_wall.end.X = p2.X;
new_wall.end.Y = p2.Y;
new_wall.Cal_Equation();
Mywall.Add(new_wall);
}
