public void tick() {
		time++;
		if (time > 60) {
			remove();
		}
		xx += xa;
		yy += ya;
		zz += za;
		if (zz < 0) {
			zz = 0;
			za *= -0.5;
			xa *= 0.6;
			ya *= 0.6;
		}
		za -= 0.15;
		x = (int) xx;
		y = (int) yy;
	}