Question

所以在这个游戏中我正在测试，每当球击中球拍时，我希望得分增加1.但相反，它会增加9。我怎样才能解决这个问题？这是代码。第二种方法是update（）方法，包含分数增加。

public class PlayState extends State {
    private Catcher catcher;
    private Ball ball;
    boolean visible  ;
    private int playerScore = 0;
    private Font scoreFont;

    @Override
    public void init() {
        catcher = new Catcher(400,425,80,25);
        ball= new Ball(200,0,40,40);
    }

    @Override
    public void update() {
        visible=true;
        catcher.update();
        ball.update();
        if(ballCollides(catcher)){
            playerScore++;
            visible = false;
        }
    }

    @Override
    public void render(Graphics g) {
        //Draw Background
        g.setColor(Color.blue);
        g.fillRect(0, 0, GameMain.GAME_WIDTH, GameMain.GAME_HEIGHT);

        //Draw Ball(s)
        if(visible == true){
            g.setColor(Color.green);
            g.fillOval(ball.getX(),ball.getY(),ball.getWidth(),ball.getHeight());
        }

        // Draw catcher
        g.setColor(Color.white);
        g.fillRect(catcher.getX(), catcher.getY(), catcher.getWidth(),
                   catcher.getHeight());

        // Draw Score
        g.setFont(scoreFont); // Sets scoreFont as current font
        g.setColor(Color.white);
        g.drawString("" + playerScore, 350, 40); // Draws String using current font
    }

    @Override
    public void onClick(MouseEvent e) {
        // TODO Auto-generated method stub
    }

    @Override
    public void onKeyPress(KeyEvent e) {
        // TODO Auto-generated method stub

        if (e.getKeyCode() == KeyEvent.VK_RIGHT){
            catcher.moveRight();
        }
        if (e.getKeyCode()==KeyEvent.VK_LEFT){
            catcher.moveLeft();
        }
    }

    private boolean ballCollides(Catcher c) {
        return ball.getRect().intersects(c.getRect());
    }

    @Override
    public void onKeyRelease(KeyEvent e) {
        // TODO Auto-generated method stub
        if (e.getKeyCode() == KeyEvent.VK_LEFT
            || e.getKeyCode() == KeyEvent.VK_RIGHT) {
            catcher.stop();
        }
    }
}

正在调用更新方法的第二代代码

package com.jamescho.game.main;

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;

import javax.swing.JPanel;

import com.jamescho.framework.util.InputHandler;
import com.jamescho.game.state.LoadState;
import com.jamescho.game.state.State;

@SuppressWarnings("serial")
public class Game extends JPanel implements Runnable {
    private int gameWidth;
    private int gameHeight;
    private Image gameImage;
private Thread gameThread;
private volatile boolean running;
private volatile State currentState;

private InputHandler inputHandler;

public Game(int gameWidth, int gameHeight) {
    this.gameWidth = gameWidth;
    this.gameHeight = gameHeight;
    setPreferredSize(new Dimension(gameWidth, gameHeight));
    setBackground(Color.BLACK);
    setFocusable(true);
    requestFocus();
}

public void setCurrentState(State newState) {
    System.gc();
    newState.init();
    currentState = newState;
    inputHandler.setCurrentState(currentState);
}

@Override
public void addNotify() {
    super.addNotify();
    initInput();
    setCurrentState(new LoadState());
    initGame();
}

private void initGame() {
    running = true;
    gameThread = new Thread(this, "Game Thread");
    gameThread.start();
}

@Override
public void run() {
    // These variables should sum up to 17 on every iteration
    long updateDurationMillis = 0; // Measures both update AND render
    long sleepDurationMillis = 0; // Measures sleep
    while (running) {
        long beforeUpdateRender = System.nanoTime();
        long deltaMillis = updateDurationMillis + sleepDurationMillis;

        updateAndRender(deltaMillis);

        updateDurationMillis = (System.nanoTime() - beforeUpdateRender) / 1000000L;
        sleepDurationMillis = Math.max(2, 17 - updateDurationMillis);

        try {
            Thread.sleep(sleepDurationMillis);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
    // End game immediately when running becomes false.
    System.exit(0);
}

private void updateAndRender(long deltaMillis) {
    currentState.update(deltaMillis / 1000f);
    prepareGameImage();
    currentState.render(gameImage.getGraphics());
    renderGameImage(getGraphics());
}

private void prepareGameImage() {
    if (gameImage == null) {
        gameImage = createImage(gameWidth, gameHeight);
    }
    Graphics g = gameImage.getGraphics();
    g.clearRect(0, 0, gameWidth, gameHeight);
}

public void exit() {
    running = false;
}

private void renderGameImage(Graphics g) {
    if (gameImage != null) {
        g.drawImage(gameImage, 0, 0, null);
    }
    g.dispose();
}

private void initInput() {
    inputHandler = new InputHandler();
    addKeyListener(inputHandler);
    addMouseListener(inputHandler);
}

}

Answer 1

对于单个冲突，似乎// Example using a single previousCollides state variable... // Not suitable for a multi catcher / multi-ball game. // The modifications break the contract this methods name seems to // imply so the previousCollides logic should probably exist elsewhere // and this code is only to illustrate the idea. private boolean ballCollides(Catcher c) { boolean collides = ball.getRect().intersects(c.getRect()); boolean result = collides && !previousCollides; previousCollides = collides; return result; }可能会在多个更新中返回true。如果不查看整个程序的代码，我不确定这一点，但根据已发布的内容，这似乎是最可能的情况。

一个修复方法是跟踪每个捕手和球组合的先前碰撞状态（如果可能有多个球和捕手），并且仅在当前状态发生碰撞时更新得分并且之前的状态没有碰撞。

E.g。

angular.module('app', [])
    .directive('myDirective', function () {
    return {
        restrict: 'E',
        scope: {
            logoSrc: '@',
            header: '@',
            body: '@'
        }
    };
});

<my-directive header="header"
              body="body"
              logo-src="logoSrc.png">
</my-directive>

以上只是一个示例，实际跟踪以前的碰撞数据取决于您。也许它应该保留在捕手对象本身内，因为这似乎是最有意义的。

玩家得分增加9而不是1

1 个答案: