void OnGameTick()
{
	...
	
	if (player[0].x == 25 && (player[0].y == 25)    //once the player crosses [25,25]...
        {
		if (music.filename != "cooba.mp3")
                        music.filename = "cooba.mp3";    //...the music will change...
                        music.play("cooba.mp3");        //...and begin playing
	}	
	...
}