int player_move_dir = game_em.last_player_direction[player_nr];
int dx = SIGN(screen_x - screen_x_old);
int dy = SIGN(screen_y - screen_y_old);
int player_move_dir = game_em.last_player_direction[player_nr];
int dx = SIGN(screen_x - screen_x_old);
int dy = SIGN(screen_y - screen_y_old);