for airship in vessels:
if i==0:
airship.carry_out_order()
airship.update(1./FRAMES_PER_SECOND, world_map.get_wind_vector())
# let's move the ship
#airship.move(1./FRAMES_PER_SECOND, world_map.get_wind_vector())
# ...and turn it
#airship.turn(1./FRAMES_PER_SECOND)
# add some markers each second, to show the ships movement
# check if we need to scroll the background
ship_screen_pos = world_map.get_screen_coords(airship.position)
#print "ship_screen_pos:", ship_screen_pos
d = 0.3
if ship_screen_pos.x > SWIDTH - SWIDTH*d:
#print "X+"
world_map.position.x += ship_screen_pos.x - (SWIDTH - SWIDTH*d)
if ship_screen_pos.x < SWIDTH * d:
#print "X-"
world_map.position.x += ship_screen_pos.x - SWIDTH * d
if ship_screen_pos.y > SHEIGHT - SHEIGHT * d:
#print "Y+"
world_map.position.y += ship_screen_pos.y - (SHEIGHT - SHEIGHT * d)
if ship_screen_pos.y < SHEIGHT * d:
#print "Y-"
world_map.position.y += ship_screen_pos.y - SHEIGHT * d
