如何确保玩家不穿墙

Question

我正在编程我的第一个实际2D游戏（吃豆人）。我认为比赛看起来不错，但我有一个大问题--碰撞。对象仍然存在，我被困住了，所以我决定寻求有丰富经验的真正程序员的帮助。（我当然做了一些研究，但我不想做复制粘贴之类的事情，因为我没搞懂）。就像我说的，游戏差不多完成了，我所需要做的就是让帕克曼继续前进。像例子一样，我画大的白色矩形作为平台。我希望有人能帮助我。在这个项目中，我学到了很多东西，碰撞是我理解的东西，但不知道如何正确地编程它。我想我已经快弄明白了，但还是少了点什么。

PS：我在windowbuilder中创建了windows，所以编译可能会有问题：（

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Rectangle;
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;
import javax.swing.border.EmptyBorder;

public class Main extends JFrame implements ActionListener{
    JPanel contentPane;
    Rectangle packman ;
    Rectangle platform;
    Rectangle secondPlat;

    private int count = 0;
    private int x = 170, y = 50;
    private int xVel = 1, yVel = 1;
    Timer timer;

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        Main frame = new Main();
        frame.setVisible(true);
    }

    public Main() {
        // TODO Auto-generated constructor stub
        this.setSize(500,500);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        setContentPane(contentPane);
        getContentPane().setBackground(Color.gray);
        packman = new Rectangle(x,y,50,50);
        platform = new Rectangle(100,70,50,100);
        secondPlat = new Rectangle(220,50,50,100);
        timer = new Timer(0,this);
        timer.start();
        this.addKeyListener(new KeyListener() {

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

            @Override
            public void keyReleased(KeyEvent e) {
                // TODO Auto-generated method stub
                switch(e.getKeyCode()) {
                    case 37: //doleva
                    count = 1;  
                    repaint();
                    break;
                case 38: //nahorů       
                    count = 2;  
                    repaint();
                    break;
                case 39://doprava           
                    count = 3;          
                    repaint();
                    break;
                case 40://dolů      
                    count =4;   
                    repaint();
                    break;
                }
            }

            @Override
            public void keyPressed(KeyEvent e) {
                // TODO Auto-generated method stub
                System.out.println("Char" + e.getKeyCode());
                System.out.println("Hod" + e.getKeyCode());
            }
        });
    }

    @Override
    public void paint(Graphics g) {
        // TODO Auto-generated method stub
        super.paint(g);
        g.drawRect(x,y,packman.width,packman.height);
        g.setColor(Color.blue);
        g.fillRect(x,y,packman.width,packman.height);

        g.drawRect(platform.x,platform.y,platform.width,platform.height);
        g.setColor(Color.blue);
            
        g.drawRect(secondPlat.x,secondPlat.y,secondPlat.width,secondPlat.height);
        g.setColor(Color.blue);
    }

    @Override
    public void actionPerformed(ActionEvent arg0) {
        // TODO Auto-generated method stub
        if (count == 1) {
            x = x - xVel;
            repaint();
            zkontrolujKolizi();
        }
        
        if (count ==2) {
            y = y - yVel;
            repaint();
            zkontrolujKolizi();
        }
        if (count ==3) {
            x = x + xVel;
            repaint();
            zkontrolujKolizi();
        }
        if (count ==4) {
            y  = y+yVel; 
            repaint();
            zkontrolujKolizi();
        }
    }

    public void zkontrolujKolizi() {
        // TODO Auto-generated method stub
        if (packman.intersects(platform) || packman.intersects(secondPlat)) {
            System.out.println("Got ya!");
        }
    }
}

Answer 1

在您的代码中，您更新了x和y，但这并不是在“packman”对象中完成的，该对象总是位于其初始位置；所以当你检查与墙的交叉点时，包装员总是在(170，50)；我同时更改了动画方法以反映packman和paint方法中的变化，以便您使用更新的packman坐标。

动画：

@Override
public void actionPerformed(ActionEvent arg0) {
    // TODO Auto-generated method stub
    if (count == 1) {
        packman.x = packman.x - xVel;
        repaint();
        zkontrolujKolizi();
        
    
    }
    
    if (count ==2) {
        packman.y = packman.y - yVel;
        repaint();
        zkontrolujKolizi();
    }
    if (count ==3) {
        packman.x = packman.x + xVel;
        repaint();
        zkontrolujKolizi();
    }
    if (count ==4) {
        packman.y  = packman.y+yVel; 
        repaint();
        zkontrolujKolizi();
    }
    
    
}

油漆：

@Override
    public void paint(Graphics g) {
        // TODO Auto-generated method stub
        super.paint(g);
        g.drawRect(packman.x,packman.y,packman.width,packman.height);
        g.setColor(Color.blue);
        g.fillRect(packman.x,packman.y,packman.width,packman.height);
        
        g.drawRect(platform.x,platform.y,platform.width,platform.height);
        g.setColor(Color.blue);
        
        g.drawRect(secondPlat.x,secondPlat.y,secondPlat.width,secondPlat.height);
        g.setColor(Color.blue);
        
    }

为避免移动墙壁，计算新位置，检查冲突，如果为真，回滚位置更改：

@Override
public void actionPerformed(ActionEvent arg0) {
    int rollbackX=packman.x;
    int rollbackY=packman.y;

    switch (count) {
    case 1:
        packman.x = packman.x - xVel;
        break;
    case 2:
        packman.y = packman.y - yVel;
        break;
    case 3:
        packman.x = packman.x + xVel;
        break;
    case 4:
        packman.y  = packman.y+yVel;
        break;
    }

    //Collision found, rollback
    if (zkontrolujKolizi()) {
        packman.x=rollbackX;
        packman.y=rollbackY;
    } else {        
        repaint();
    }
}

public boolean zkontrolujKolizi() {
    return packman.intersects(platform) || packman.intersects(secondPlat);
}