绘制大量圆圈的最有效方法 java.

Question

好的，所以我环顾四周，没有找到任何对我有帮助的东西，所以我想我会继续在这里问。我想要一堆碰撞反弹的圆圈，并且通常相互交互。我遇到的问题是画很多圆圈会消耗帧速率。所以给定一个我必须画的圆圈阵列，所有这些圆圈。绘制它们的唯一方法是否只是在paintComponent中使用g.fillOval（）将它们全部绘制？

例如，在 paint 组件中，我调用一个函数 drawBalls（Graphics2D g），它绘制它包含的所有球。（这就是我通过将东西传递给绘制的对象来绘制东西的方式，我不知道是否有更好的方法）

    for(Ball ball:balls){
        ball.drawYourself(g) //g is the Graphics2D
    }

谢谢

对不起，如果这是一个糟糕的问题，这是我的程序代码。我希望它不会太长。

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.awt.image.*; 
import java.io.*; 
import javax.imageio.*; 
import java.util.*;
import javax.swing.Timer;
//###################################################\
public class Game extends JFrame implements ActionListener{
    private Timer myTimer;   
    private GamePanel panel;
    public Game() {
        super("Things.py");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setSize(1000,800);
        panel = new GamePanel(this);
        add(panel);
        myTimer = new Timer(1, this);
        myTimer.start();
        setResizable(false);
        setVisible(true);
    }
    public void actionPerformed(ActionEvent evt){
        panel.repaint();        
    }
    public static void main(String[] arguments) {
        Game frame = new Game();        
    }
}
//###################################################\
//###################################################\
class GamePanel extends JPanel implements MouseMotionListener, MouseListener,KeyListener{
    // ------------ Variables ----------------------------------------------
    private int mx,my;//Mouse position x and y
    private boolean[]keys;//If the keys are pressed
    private Boolean mousepressed=false;//If the mouse is pressed down
    private Game mainframe;//The panel that created this GamePanel
    private Color backmenuc;
    private Color backcolor;
    private bounceBalls bballs;
    private bounceBalls bballs2;
    // ------------ Constructor --------------------------------------------
    public GamePanel(Game m){
        //----- Listeners -----
        addMouseMotionListener(this);//LISTEN TO ME!!!
        addMouseListener(this);//Listen to me!
        addKeyListener(this);//listen to me pls
        //----- Variables -----
        mainframe=m;
        keys=new boolean[KeyEvent.KEY_LAST+1];//creates the array for keys
        backcolor=new Color(0,0,0);
        backmenuc=new Color(255,255,255);
        bballs=new bounceBalls(this);
        bballs2=new bounceBalls(this);
        //----- Load Images -----
        //----- End -----
    }
    // ------------ Drawing ------------------------------------------------
    public void paintComponent(Graphics gg){
        Graphics2D g=(Graphics2D) gg;
        paint.drawRect(g,0,0,getWidth(),getHeight(),backcolor);
        if (mousepressed){
            bballs.addBall(mx,my,10);
            bballs2.addBall(mx+100,my,10);
        }
        bBallThreading b1=new bBallThreading(g,bballs,"B1");
        b1.start();
        bBallThreading b2=new bBallThreading(g,bballs2,"B1");
        b2.start();
        //bballs.update();
        //bballs2.update();
        bballs.draw(g);
        bballs2.draw(g);
        System.out.println(bballs.size());
    }
    // ------------ Misc ---------------------------------------------------
    public void addNotify() {
        super.addNotify();
    }
    // ------------ MouseListener ------------------------------------------
    public void mouseEntered(MouseEvent e) {}
    public void mouseExited(MouseEvent e) {}
    public void mouseReleased(MouseEvent e) {
        mousepressed=false;
    }    
    public void mouseClicked(MouseEvent e){
        }  
    public void mousePressed(MouseEvent e){ 
        mousepressed=true;
    }   
    // ---------- MouseMotionListener --------------------------------------
    public void mouseDragged(MouseEvent e){
        mx=e.getX();
        my=e.getY();
    }
    public void mouseMoved(MouseEvent e){
        mx=e.getX();
        my=e.getY();
        }
    // ---------- KeyListener -----------------------------------------------
    public void keyTyped(KeyEvent e) {}
    public void keyPressed(KeyEvent e) {
        keys[e.getKeyCode()] = true;
    }
    public void keyReleased(KeyEvent e) {
        keys[e.getKeyCode()] = false;
    }
}
//###################################################\
class bounceBall{
    private double bx,by;
    private int br;
    private double vx,vy;
    public bounceBall(int x,int y,int radius){
        bx=(double)x;
        by=(double)y;
        br=radius;
        vx=0;
        vy=0;
    }
    public void move(){
        if((by+vy)>800){
            vy*=-.9;
        }
        bx+=vx;
        by+=vy;
    }
    public void addV(double x, double y){
        vx+=x;
        vy+=y;
    }
    public void draw(Graphics2D g){
        g.setColor(new Color(255,0,0));
        g.fillOval((int)bx-br,(int)by-br,br*2,br*2);
    }
}
class bounceBalls{
    GamePanel gp;
    ArrayList<bounceBall> balls;
    double gravity;
    public bounceBalls(GamePanel gamep){
        gp=gamep;
        gravity=.1;
        balls=new ArrayList<bounceBall>();
    }
    public void draw(Graphics2D g){
        //paint.setAA(g,true);
        paint.setAlpha(g,.1f);
        for(bounceBall ball:balls.toArray(new bounceBall[balls.size()])){
            ball.draw(g);
        }
        paint.setAlpha(g,1f);
        //paint.setAA(g,false);
    }
    public void setGravity(double g){
        gravity=g;
    }
    public void update(){
        for(bounceBall ball:balls.toArray(new bounceBall[balls.size()])){
            ball.addV(0,gravity);
            ball.move();
        }
    }
    public void addBall(int x, int y, int radius){
        balls.add(new bounceBall(x,y,radius));
    }
    public int size(){
        return balls.size();
    }
}
class bBallThreading implements Runnable{
    private Thread t;
    private String threadname;
    Graphics2D g;
    private bounceBalls bballs;
    public bBallThreading(Graphics2D g, bounceBalls bballs,String s){
        this.g=g;
        this.bballs=bballs;
        threadname=s;
    }
    public void run(){
        bballs.update();
    }
    public void start(){
        if (t == null)
      {
         t = new Thread (this, threadname);
         t.start ();
      }
    }
}
//###################################################\

当我运行这个时，我以 4000 fps 的速度得到 30 个圆圈

Answer 1

    bBallThreading b1=new bBallThreading(g,bballs,"B1");
    b1.start();
    bBallThreading b2=new bBallThreading(g,bballs2,"B1");
    b2.start();

paintComponent（） 方法用于绘画。这就是应该做的。

您不应该在绘画方法中启动线程。每次 Swing 绘制组件时，您都会启动另外两个线程。

向该方法添加一个 System.out.println（...） 语句，以查看该方法执行了多少次。

您应该在启动动画时启动线程。