def update(dt):
destroy_me = []
for entity_id, state in enemies.iteritems():
position = spatial.get_position(entity_id)
direction = state.direction
if state.state == STATE_HORIZONTAL:
relevant_axis = position[0]
relevant_movement = state.horizontal_movement
move_direction = [direction, 0]
next_state = STATE_VERTICAL
next_nextdirection = direction * -1
elif state.state == STATE_VERTICAL:
relevant_axis = position[1]
relevant_movement = state.vertical_movement
move_direction = [0, direction]
next_state = STATE_HORIZONTAL
next_nextdirection = -1
target = state.target
if target is None:
target = relevant_axis + relevant_movement * direction
distance = (target - relevant_axis) * direction
jetengine.move(entity_id, move_direction)
if distance < 0:
target = None
state.state = next_state
state.next_direction, state.direction = next_nextdirection, state.next_direction
if position[1] < DESTROY_THRESHOLD_Y:
destroy_me.append(entity_id)
state.target = target
for entity_id in destroy_me:
manager.destroy_entity(entity_id)
