import java.awt.*;

public class BackEffect {
int x, y;
int r; //半径
double ra; //角度
int speed_r;
int speed_ra;
int size;
/*********************************************************************
					　	　コンストラクタ
**********************************************************************/	
	public BackEffect() {
		x = 0;
		y = 0;
		r = 0;
		ra = 0;
		speed_r = 0;
		speed_ra = 0;
		size = 0;
	}
/*********************************************************************
					初期化
**********************************************************************/	
	public void init(){
		x = 0;
		y = 0;
		r = 0;
		ra = 0;
		size = 0;
	}

/*********************************************************************
					星を描く
**********************************************************************/	
	public void draw(Graphics off_g){
		move();//星を動かす
		off_g.fillOval(320+x,240+y,3,3);
	}

/*********************************************************************
					大きい星を描く
**********************************************************************/	
	public void draw2(Graphics off_g){
		move2();//星を動かす
		off_g.fillOval(320+x,240+y,size,size);
	}


/*********************************************************************
					星を動かす
**********************************************************************/	
	public void move(){
		if (r == 0){ //初期の設定
			ra = Math.random()*Math.PI*2;
			speed_ra = (int)(8 + (Math.random()*8));
			speed_r = (int)(1 + (Math.random()*4));

		}

		x = (int)(r*Math.cos(ra)*(double)4/3);
		y = (int)(r*Math.sin(ra));
		
		
		ra += Math.PI/speed_ra;
		if (ra >= 2*Math.PI)
		ra = 0;

		r += speed_r;
		if (r > 240)
		r = 0;
		
	}


/*********************************************************************
					大きい星を動かす
**********************************************************************/	
	public void move2(){
		if (r == 0){ //初期の設定
			ra = Math.random()*Math.PI*2;
			speed_ra = (int)(4 + (Math.random()*4));
			speed_r = (int)(5 + (Math.random()*5));
			size = 4 + (int)(Math.random()*3);
		}

		x = (int)(r*Math.cos(ra)*(double)4/3);
		y = (int)(r*Math.sin(ra));
		
		ra += Math.PI/speed_ra;
		if (ra >= 2*Math.PI)
		ra = 0;

		r += speed_r;
		if (r > 240)
		r = 0;

	}

}