constants
	w = 300
	angle = 90  works; angle = 130 doesn't work

Wall 1:
    a = angle
    start_x = 400
    start_y = 400
    center_x = start_x + (w/2) * cos(a)
    center_y = start_y + (w/2) * sin(a)
    end_x = start_x + w * cos(a)
    end_y = start_y + w * sin(a)
	=> Draw wall at (center_x,center_y) with angle a

Wall 2:
    a = a + angle
    start_x = end_x
    start_y = end_y
    center_x = start_x + (w/2) * cos(a)
    center_y = start_y + (w/2) * sin(a)
    end_x = start_x + w * cos(a)
    end_y = start_y + w * sin(a)
	=> Draw wall at (center_x,center_y) with angle a

Wall 3:
    a = a + angle
    start_x = end_x
    start_y = end_y
    center_x = start_x + (w/2) * cos(a)
    center_y = start_y + (w/2) * sin(a)
    end_x = start_x + w * cos(a)
    end_y = start_y + w * sin(a)
	=> Draw wall at (center_x,center_y) with angle a