package ddd; 
import java.awt.*; 
import javax.swing.JFrame; 
public class Cardioid extends JFrame { 
  //獲取屏幕大小 
  private static final int WIDTH = 500; 
  private static final int HEIGHT = 500;   
  private static int WINDOW_WIDTH = Toolkit.getDefaultToolkit().getScreenSize().width; 
  private static int WINDOW_HEIGHT = Toolkit.getDefaultToolkit().getScreenSize().height; 
  public Cardioid(){ 
    super("I love you");//設置窗口標題 
    this.setBackground(Color.BLACK); 
    this.setLocation((WINDOW_WIDTH-WIDTH)/2,(WINDOW_HEIGHT-HEIGHT)/2);//設置窗口位置 
    this.setSize(WIDTH, HEIGHT);//設置窗口大小 
    this.setLayout(getLayout());//設置窗口布局 
    this.setVisible(true);//設置窗口可見 
    this.setDefaultCloseOperation(DISPOSE_ON_CLOSE);//設置窗口默認關閉方式 
  } 
  public void paint(Graphics g){ 
    double x,y,r;//橫縱坐標以及半徑 
    Image image = this.createImage(WIDTH, HEIGHT); 
    Graphics pic = image.getGraphics(); 
    for (int i = -2; i < 90; i++) { 
      for (int j = -2; j < 90; j++) { 
        r=Math.PI/45+Math.PI/45*i*(1-Math.sin(Math.PI/45*j))*18; 
        x=r*Math.cos(Math.PI/45*j)*Math.sin(Math.PI/45*i)+WIDTH/2; 
        y=-r*Math.sin(Math.PI/45*j)+HEIGHT/3; 
        pic.setColor(Color.MAGENTA); 
        pic.fillOval((int)x, (int)y, 2, 2); 
      } 
      g.drawImage(image,0,0,this);//生成圖片 
    } 
  }  
  public static void main(String[] args) { 
    new Cardioid(); 
  } 
}