ball() : position(0.0), velocity(0.0), radius(BALL_RADIUS), mass(BALL_MASS) {
		index = ballIndexCnt++; Reset();
}

ball(){
	position(0.0);
	velocity(0.0);
	radius(BALL_RADIUS);
	mass(BALL_MASS);
	index = ballIndexCnt++; Reset();
}