具有平台碰撞和跳跃的奇怪行为 [英] Strange behavior with platform collision and jumping
问题描述
我使用AWT和Swing开发了一个简单的Java游戏.您要做的就是用空格键控制一个正方形,该空格键可以上下跳跃到无休止的平台流中.
I have developed a simple game in java using AWT and Swing. All you do is control a square with the spacebar that jumps up and down onto a never-ending stream of platforms.
一切正常,但是当玩家跳下平台,握住空格键并降落在另一个平台上时,他/她将随机弹跳或简单地跌落平台.据我所知,错误与播放器的行为有关.
Everything works fine, but when a player jumps off a platform, holds the spacebar, and lands on another platform, he/she will randomly bounce or simply drop through the platform. From what I can tell, the error lies somewhere with the Player's behavior.
这是测试它的全部代码:
Here's the all the code needed to test it:
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.Timer;
public class main {
private static JFrame gui;
private static Container pane;
private static JPanel panel;
public static void main(String[] args) {
gui = new JFrame();
gui.setSize(500,500);
gui.setTitle("An Experiment");
gui.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
pane=gui.getContentPane();
panel = new ColorPanel(Color.WHITE, 500, 500);
pane.add(panel);
gui.setVisible(true);
gui.pack();
}
//****************
//ColorPanel class
//****************
private static class ColorPanel extends JPanel{
private static final long serialVersionUID = -1101242028703991986L;
private Timer timer, dtimer;
private KeyListener k;
private Platform platform;
private Player player;
private int difficulty, score;
public ColorPanel(Color backColor, int width, int height){
setBackground(backColor);
setPreferredSize(new Dimension(width, height));
difficulty=-1;
score=0;
platform = new Platform(new Point(240,250), 50);
player=new Player(width/2, height/2-100);
k=new keyboardListener();
addKeyListener(k);
setFocusable(true);
timer = new javax.swing.Timer(15, new timerListener());
timer.start();
dtimer = new javax.swing.Timer(50000, new difficultyListener());
dtimer.start();
}
public void paintComponent(Graphics g){
super.paintComponent(g);
if(player.getY()<500){
platform.draw(g);
player.draw(g);
}else{
timer.stop();
dtimer.stop();
setBackground(Color.BLACK);
g.setColor(Color.RED);
g.drawString("Game Over.", 215, 230);
g.setColor(Color.YELLOW);
g.drawString("Platforms cleared: "+score, 200, 240);
g.drawString("End difficulty: "+Math.abs(difficulty), 200, 250);
}
}
private class timerListener implements ActionListener{
public void actionPerformed(ActionEvent e){
//Player control
player.move(platform);
repaint();
}
}
private class difficultyListener implements ActionListener{
public void actionPerformed(ActionEvent e){
difficulty--;
if(difficulty<=-10){
dtimer.stop();
}
}
}
private class keyboardListener implements KeyListener{
@Override
public void keyPressed(KeyEvent e){
//space=32
if(e.getKeyCode()==32){
player.setJumping(true);
}
}
@Override
public void keyReleased(KeyEvent e){
if(e.getKeyCode()==32){
player.setJumping(false);
}
}
@Override
public void keyTyped(KeyEvent e) {
}
}
}
//************
//Player class
//************
private static class Player {
private int x, y, w, h, initialSpeed, speed, endingSpeed, acceleration, jumpHeight, timeCount;
private boolean isJumping, onPlatform;
private Timer accel;
public Player(int x1, int y1){
x=x1;
y=y1;
w=15;
h=15;
isJumping=false;
onPlatform=false;
speed=3;
accel=new Timer(50, new timerListener());
}
public void draw(Graphics g){
g.drawRect(x, y, w, h);
}
public void move(Platform p){
//platform collision
onPlatform=false;
if((x>p.getP1().getX() && x<p.getP2().getX()) || (x+w>p.getP1().getX() && x+w<p.getP2().getX())){
if(Math.abs(y+h-p.getP1().getY())<2){
onPlatform=true;
}
}
//speed update and movement
if(isJumping && y>0 && jumpHeight>=-140){
y+=speed;
jumpHeight+=speed;
}else if(onPlatform){
speed=0;
}else if(!onPlatform){
jumpHeight=0;
if(!isJumping && speed!=3){
setSpeed(3);
}
y+=speed;
}
if(jumpHeight<-140){
jumpHeight=0;
}
}
public void setJumping(boolean b){
if(onPlatform && b && jumpHeight>=-140){
isJumping=true;
speed=-4;
}else{
isJumping=false;
setSpeed(3);
}
}
public int getY(){
return y;
}
public void setSpeed(int s){
//speed=starting speed + acceleration*time
timeCount=0;
initialSpeed=speed;
endingSpeed=s;
if(speed>s){
acceleration=-1;
}else{
acceleration=1;
}
accel.start();
}
private class timerListener implements ActionListener{
public void actionPerformed(ActionEvent e){
timeCount++;
if(Math.abs(speed-endingSpeed)<=0.5){
accel.stop();
}else if(acceleration<0 && initialSpeed+acceleration*timeCount>0){
speed--;
}else{
speed=initialSpeed+acceleration*timeCount;
}
}
}
}
//**************
//Platform class
//**************
private static class Platform {
private Point p1, p2;
public Platform(Point p, int l){
p1=p;
p2=new Point((int)(p1.getX()+l), (int)(p1.getY()));
}
public Point getP1(){
return p1;
}
public Point getP2(){
return p2;
}
public void draw(Graphics g){
g.drawLine((int)(p1.getX()), (int)(p1.getY()), (int)(p2.getX()), (int)(p2.getY()));
}
}
}
推荐答案
很难百分百确定,但是看起来"到底是怎么回事,是您在 Space 事件想做的事以及您的重力"想做的事.
It's difficult to be 100% sure, but what it "looks" like is happening, is you have a fight between what the Space event wants to do and what your "gravity" wants to do.
请记住,当 Space 按下时,您将收到多个按键事件,具体取决于操作系统的键盘延迟/定时(例如,您每秒可能收到多个事件)
Remember, while the Space is down, you will be receiving multiple key events depending on the OS's keyboard delay/timing (you may receive several events per second for example)
而不是让用户像...那样按下键.
Instead of allowing the user to keep the key down like...
private class keyboardListener implements KeyListener{
@Override
public void keyPressed(KeyEvent e){
//space=32
if(e.getKeyCode()==32){
player.setJumping(true);
}
}
@Override
public void keyReleased(KeyEvent e){
if(e.getKeyCode()==32){
player.setJumping(false);
}
}
@Override
public void keyTyped(KeyEvent e) {
}
}
尝试忽略任何新的 Space 事件...
Try ignoring any new Space events...
我要做的是添加一个称为 hasJumped
之类的标志.当它为 true
时,您只需忽略任何新的跳转事件.用户释放 Space 后,您将重置该标志,以便再次按下 Space 会导致新的跳转.
What I would do is add a flag called something like hasJumped
. While it's true
, you would simply ignore any new jump events. Once the user releases the Space, you reset the flag so another press on Space would cause a new jump.
在您的游戏引擎中,我将重置 jumping
标志,以便一旦您注册了发生跳跃的事实,直到释放并按下 Space 再次,它不会触发跳跃...
In you game engine, I would reset the jumping
flag so that once you've registered the fact that a jump has occurred, until they release and press the Space again, it won't trigger a jump...
private class keyboardListener implements KeyListener{
@Override
public void keyPressed(KeyEvent e){
//space=32
if(e.getKeyCode()==32){
if (!player.hasJumped()) {
player.setJumping(true);
}
}
}
@Override
public void keyReleased(KeyEvent e){
if(e.getKeyCode()==32){
player.hasJumped(false);
}
}
//...
}
我还建议您查看键绑定通过 KeyListener
您可以看一下 查看全文