java - 创建简单的碰撞检测

Question

我创建了一个非常简单的程序，其中使用 Paint 绘制了一个迷宫(fillRect 方法用于创建迷宫的墙壁)，并且创建了一个使用 keyListener 移动的 Sprite 。我想实现一个简单的(因为我在通勤科学的第一年)碰撞检测，以防止 Sprite 穿过迷宫的墙壁。因为迷宫是用近 400 行代码绘制的，所以我不会包含它。

import java.awt.*;
import java.applet.*;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

public class IndeProj extends Applet implements KeyListener {


    //KEY LISTENER INFO FOR MY SPRITE
    public int x = 10;
    public int y = 575;
    public boolean keyUp;  
    public boolean keyDown;  
    public boolean keyLeft;  
    public boolean keyRight;


    public void paint(Graphics g) {
        //drawMaze
        drawMazeHorizontalLines(g);
        drawMazeVerticalLines(g);

        //SPRITE STUFF
        addKeyListener(this);
        this.MoveRect(g,x,y);

    }

    public void drawMazeHorizontalLines(Graphics g)
    {
        //This method draws the horizontal lines of the maze using the method `fillRect(x,y,w,h)`
    }

    public void drawMazeVerticalLines (Graphics g)
    {
        //This method draws the vertical lines of the maze using `fillRect(x,y,w,h)`
    }


    public void MoveRect(Graphics g, int x, int y) //Draws Sprite   
    {
        g.setColor(Color.green);
        g.fillRect(x,y,20,20);
        g.setColor(Color.yellow); //Sprite body
        g.fillRect(x,y,20,20);
        g.setColor(Color.green); //Sprite eyes
        g.fillRect(x,y,7,7);
        g.fillRect((x+13),y,7,7);
        g.setColor(Color.blue); //Sprite pants
        g.fillRect(x,(y+13),20,7);
        g.setColor(Color.black); //Sprite mouth
        g.fillRect((x+6),(y+9),8,2);
    }

    public void keyPressed(KeyEvent e) //Moves Sprite
    {
        if (e.getKeyCode() == KeyEvent.VK_DOWN) {
            y+=1;
            y+=0;
        } if (e.getKeyCode() == KeyEvent.VK_UP) {
            y-=1;
            y-=0;
        } if (e.getKeyCode() == KeyEvent.VK_LEFT) {
            x-=1;
            x-=0;
        } if (e.getKeyCode() == KeyEvent.VK_RIGHT) {
            x+=1;
            x+=0;
        }
        repaint();
    }
    public void keyReleased(KeyEvent e) //Stops Sprite  
    {   
         keyUp = keyDown = keyLeft = keyRight = false;
    }
}

我想让 Sprite 在撞到墙壁时停止(使用x和y坐标)， Sprite 将停止移动。

Answer 1

这是一种简单的碰撞检测方法， map 是一个由每个整数组成的网格它包含的墙。如果你做错了，你会得到神奇的单向墙。

/* could use enums for this */
public static int WALL_LEFT = 1;
public static int WALL_RIGHT = 2;
public static int WALL_TOP = 4;
public static int WALL_BOTTOM = 8;


public int[][] createSimpleMap(){
    int[][] map = new int[2][2];
    map[0][0] = WALL_LEFT | WALL_RIGHT | WALL_TOP;
    map[0][1] = WALL_LEFT | WALL_RIGHT | WALL_TOP;
    map[1][0] = WALL_LEFT | WALL_BOTTOM;
    map[1][1] = WALL_RIGHT | WALL_BOTTOM;
    return map;
}

要进行碰撞检测，只需检测墙壁是否存在。

public boolean canMoveUp(x,y){
    return (this.map[x][y] & WALL_TOP) ==0;
}