我刚刚做了一个关于如何使 2d 背景上的角色基本上像一个非常有限的平台游戏一样移动的教程,没有重力或任何东西,我遇到了一些滞后,我假设这是因为按键/释放的方式有效,但我想知道是否有任何方法可以优化它,可能是我没有动画,它只是一个 block ,但我不确定,就像我按住左键然后放开左键一样一直按住向右,它就会上升,直到我放手,它会在左右之间滞后,等等。我将粘贴下面的代码。谢谢!:
//@@@MAIN CLASS, NAMED CHECKERS ARBITRARILY
import javax.swing.*;
public class Checkers {
public static void main(String[] args) {
JFrame frame = new JFrame("2D Game");
frame.add(new Board());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(1200,326);
frame.setVisible(true);
}
}
//@@@@@@@@@@@@@@@@@
//class called Dude this is my character(circle)
import javax.swing.ImageIcon;
import java.awt.Image;
import java.awt.event.KeyEvent;
public class Dude {
int x, dx, y, dy;
Image still;
public Dude(){
ImageIcon i = new ImageIcon("C:/still.png");
still = i.getImage();
x = 10;
y = 150;
}
public void move(){
x = x + dx;
y = y + dy;
}
public int getX(){
return x;
}
public int getY(){
return y;
}
public Image getImage(){
return still;
}
public void keyPressed(KeyEvent e){
int key = e.getKeyCode();
if (key == KeyEvent.VK_LEFT)
dx = -2;
if (key == KeyEvent.VK_RIGHT)
dx = 2;
if (key == KeyEvent.VK_UP)
dy = -2;
if (key == KeyEvent.VK_DOWN)
dy = 2;
}
public void keyReleased(KeyEvent e){
int key = e.getKeyCode();
if (key == KeyEvent.VK_LEFT);
dx = 0;
if (key == KeyEvent.VK_RIGHT);
dx = 0;
if (key == KeyEvent.VK_UP)
dy = 0;
if (key == KeyEvent.VK_DOWN)
dy = 0;
}
}
//@@@@@@@@@@@@@@@@@@@
//this is my board class (background)
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import javax.swing.*;
public class Board extends JPanel implements ActionListener{
Dude p;
Image img;
Timer time;
public Board(){
p = new Dude();
addKeyListener(new AL());
setFocusable(true);
ImageIcon i = new ImageIcon("C:/test.png");
img = i.getImage();
time = new Timer(5, this);
time.start();
}
public void actionPerformed(ActionEvent e){
p.move();
repaint();
}
public void paint(Graphics g){
super.paint(g);
Graphics2D g2d = (Graphics2D) g;
g2d.drawImage(img, 0, 0, null);
g2d.drawImage(p.getImage(), p.getX(), p.getY(), null);
}
private class AL extends KeyAdapter{
public void keyReleased(KeyEvent e){
p.keyReleased(e);
}
public void keyPressed (KeyEvent e){
p.keyPressed(e);
}
}
}
最佳答案
这对我有用:
package sof_6406645;
import javax.swing.*;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
public class Checkers {
public static void main(String[] args) {
JFrame frame = new JFrame("2D Game");
frame.add(new Board());
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(1200,326);
frame.setVisible(true);
}
public static class Board extends JPanel implements ActionListener {
final Image img;
Point p;
final boolean[] dynamics = new boolean[4];
public Board() {
addKeyListener(new AL());
setFocusable(true);
ImageIcon i = new ImageIcon("dude.png");
img = i.getImage();
p = new Point(0,0);
Timer timer = new Timer(5, this);
timer.start();
}
public void actionPerformed(ActionEvent e){
moveImage();
}
public void moveImage (){
int dx = 0;
int dy = 0;
if(dynamics[0]) dx = -2;
if(dynamics[1]) dy = -2;
if(dynamics[2]) dx = 2;
if(dynamics[3]) dy = 2;
p.move((int)p.getX() + dx, (int)p.getY() + dy);
repaint();
}
public void paint(Graphics g){
super.paint(g);
Graphics2D g2d = (Graphics2D) g;
g2d.drawImage(img, (int)p.getX(), (int)p.getY(), null);
}
private class AL extends KeyAdapter{
public void keyReleased(KeyEvent e){
updateDynamics(e, false);
}
public void keyPressed (KeyEvent e){
updateDynamics(e, true);
}
}
final void updateDynamics(KeyEvent e, boolean v) {
int i = e.getKeyCode() - KeyEvent.VK_LEFT;
dynamics[i] = v;
}
}
}
[编辑]:
进行了较小的编辑以更正 updateDynamics()
上的 sig,并抵制了手动内联将在两个关键监听器方法中重复的(有效)1 行代码的冲动。该方法调用应该由 JIT 内联。 moveImage() 中的 if 语句序列也可以收紧,以将检查次数减半,但我再次确信 JVM 会为您解决这个问题。
说到if
,我最初并没有改变你的交互模型,但我认为如果你一直按两个相反的移动键,Dude
应该停止冷淡,你不这么认为吗?
public void moveImage (){
int dx = 0;
int dy = 0;
if(dynamics[0]) dx -= 2;
if(dynamics[1]) dy -= 2;
if(dynamics[2]) dx += 2;
if(dynamics[3]) dy += 2;
p.move((int)p.getX() + dx, (int)p.getY() + dy);
repaint();
}
关于Java代码优化,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/6406645/