我正在制作Flappy Bird的克隆。我的表现非常好：60 fps。这是它只有一个支柱/障碍的时候。一旦我添加其中3个，我的fps降至30以下。然后游戏现在无法播放。我知道这与repaint()一直有关。
以下是代码：
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.BufferedImage;
import java.util.ArrayList;
/**
* Created by Lazar on 25/05/15.
*/
public class Environment extends JComponent implements ActionListener {
public static final Dimension dimension = new Dimension(800,600);
BufferedImage img;
BufferedImage ptica1;
BufferedImage ptica2;
double skokbrojac = 0;
int brzina = 4; // speed // MUST Background % brzina = 0
int dx;
int dx2;
int pad = 0; //drop
Timer timer;
boolean parno;
boolean skok = false;
//Stubovi // Pillars
Stub stub1 = new Stub();
Stub stub2 = new Stub();
Stub stub3 = new Stub();
ArrayList<Stub>stubovi = new ArrayList<Stub>();
int razmakStub; // Space between pillars
public Environment() {
setPreferredSize(dimension);
img = Util.openImage("pozadina.png");
ptica1 = Util.openImage("ptica1.png");
ptica2 = Util.openImage("ptica2.png");
stubovi.add(stub1);
stubovi.add(stub2);
stubovi.add(stub3);
dx = img.getWidth()/2;
timer = new Timer(1000/60,this);
timer.start();
addMouseListener(new MouseAdapter() {
@Override
public void mousePressed(MouseEvent e) {
super.mousePressed(e);
skok = true; // start jump
skokbrojac = 0; //jump frame counter
}
});
}
protected void paintComponent(Graphics g){
Graphics2D g2d = (Graphics2D)g;
//g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
//g2d.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
if(dx == img.getWidth()){ //image horizontal scroll
dx2 = 0;
}
if(dx2 == img.getWidth()/2){ //image horizontal scroll
dx = dimension.width;
}
g2d.drawImage(img,getWidth() - dx, 0, null); //draw background
if(dx >= img.getWidth()){
g2d.drawImage(img,getWidth() - dx2, 0, null);
}
if(parno){
g2d.drawImage(ptica1,dimension.width/2, 290 + pad, null); //draw bird
}
else{
g2d.drawImage(ptica2,dimension.width/2, 290 + pad, null); //draw bird
}
stub1.postoji = true; //pillar1 exists?
if(razmakStub > 240){
stub2.postoji = true;
}
if(razmakStub > 480){ //pillar1 exists?
stub3.postoji = true;
}
for(Stub i : stubovi){ //draw pillars if they exist
if(i.postoji)
i.crtaj(g2d);
}
}
@Override
public void actionPerformed(ActionEvent e) {
dx = dx + brzina;
dx2 = dx2 + brzina;
if(skokbrojac > 5) // jump frame lenght
skok = false;
if(skok){
pad -= 15; // jump height
}
else{
pad += 8; //rate of the fall
}
skokbrojac++;
parno ^= true; // for different bird images
if(290 + pad >= 536 || 290 + pad<= 3) //border hit detect
timer.stop();
razmakStub += brzina;
for(Stub i : stubovi){ //reset pillars and make them move
if(i.postoji){
if(i.getDx() < -50){
i.setDx(800);
i.randomDy();
}
i.setDx(i.getDx() - brzina);
}
}
repaint();
}
}
另外请记住，这是真正的未经修饰的版本，因此代码很难看。我正在寻找一种提高性能的解决方案。
主类：
import javax.swing.*;
/**
* Created by Lazar on 25/05/15.
*/
public class Main {
public static void main(String[] args){
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
new Frame(new Environment());
}
});
}
}
框架类：
import javax.swing.*;
/**
* Created by Lazar on 25/05/15.
*/
public class Frame extends JFrame{
public Frame(JComponent content){
setContentPane(content);
setTitle("Flappy");
setDefaultCloseOperation(EXIT_ON_CLOSE);
setSize(getPreferredSize());
setResizable(false);
setVisible(true);
setLocationRelativeTo(null);
}
}
Stub / Pillar类：
import java.awt.*;
import java.awt.image.BufferedImage;
import java.util.Random;
/**
* Created by Lazar on 26/05/15.
*/
public class Stub {
BufferedImage dole;
BufferedImage gore;
Random r = new Random();
int dx = 700;
int dy = r.nextInt(250) + 250;
boolean postoji = false;
public void crtaj(Graphics2D g2d){
dole = Util.openImage("stub_dole.png");
gore = Util.openImage("stub_gore.png");
g2d.drawImage(dole, dx, dy, null);
g2d.drawImage(gore, dx, -(560-dy), null);
}
public void setDx(int dx) {
this.dx = dx;
}
public void randomDy(){
this.dy = r.nextInt(250) + 250;
}
public int getDx() {
return dx;
}
}
Ptica / Brid课程：
import java.awt.Graphics;
import java.awt.image.BufferedImage;
/**
* Created by Lazar on 26/05/15.
*/
public class Ptica {
BufferedImage ptica1;
BufferedImage ptica2;
boolean ptica;
boolean skok = false;
int pad = 0;
double skokBrojac = 0;
public Ptica(){
ptica1 = Util.openImage("/slike/ptica1.png");
ptica2 = Util.openImage("/slike/ptica2.png");
}
public void crtajPticu(Graphics g2d){
ptica ^= true;
if(ptica){
g2d.drawImage(ptica1, Environment.dimension.width/2, Environment.dimension.height/2-110 + pad, null);
}
else{
g2d.drawImage(ptica2, Environment.dimension.width/2, Environment.dimension.height/2-110 + pad, null);
}
System.out.println(pad);
}
public void setSkok(boolean skok) {
this.skok = skok;
}
public void setSkokBrojac(double skokBrojac) {
this.skokBrojac = skokBrojac;
}
public double getSkokBrojac() {
return skokBrojac;
}
public boolean isSkok() {
return skok;
}
public void setPad(int pad) {
this.pad = pad;
}
public int getPad() {
return pad;
}
}
Util类：
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.IOException;
/**
* Created by Lazar on 25/05/15.
*/
public class Util {
public static BufferedImage openImage(String name){
try {
if(!name.startsWith("/slike/")){
name="/slike/"+name;
}
return ImageIO.read(Util.class.getResource(name));
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}
答案 0 :(得分：2)
例如，您Stub Environment paintComponent调用crtaj的{{1}}课程，您可以执行以下操作...
public void crtaj(Graphics2D g2d){
dole = Util.openImage("stub_dole.png");
gore = Util.openImage("stub_gore.png");
g2d.drawImage(dole, dx, dy, null);
g2d.drawImage(gore, dx, -(560-dy), null);
}
加载图片可能需要一些时间。你应该有一个＆＃34;缓存＆＃34;管理它们的类（加载它们一次）或在创建Stub类时加载它们（我更喜欢缓存类，就像你创建和销毁许多Stub一样，加载资源在Stub类（例如构造函数）中可能会成为瓶颈
通过使用可重复使用的对象缓存（而不是重新创建对象并重新加载其资源），example能够从200-300个对象同时移动到4000以上）
答案 1 :(得分：0)
使用分析器确定代码实际花费时间的位置（请注意，YourKit提供15天免费试用许可证。）
一旦你知道你的瓶颈是什么，那么确定是否有一个简单的解决方案，如果不考虑更好的算法和数据结构，以降低代码的算法复杂性。
答案 2 :(得分：0)
按照@ alex-fitzpatrick的建议，分析总是很好。也：
Util.openImage调用创建的图像类型是否与您绘制的graphics2D对象兼容？您可能会花一些时间进行转化 (image types)。getWidth()等的调用。在对象初始化后知道这些值，缓存它们。repaint。使用overloaded version that specifies the area to repaint。