android 游戏 碰撞检测

Posted 2020-07-17 六道对穿肠

矩形碰撞 原理: 两个矩形位置 的四种情况 不是这四中情况 则碰撞

圆形碰撞 原理: 利用两个圆心之间的距离进行判定.当两个圆心的距离小于半径之和则碰撞.

像素碰撞 :不适用 遍历所有像素 检测 太多了

多矩形碰撞: 设置多个矩形碰撞检测区域 检测碰撞矩形数组 与另一碰撞矩形数组之间的位置关系.

矩形碰撞 代码:

public class MySurfaceView extends SurfaceView implements Callback, Runnable {
    private SurfaceHolder sfh;
    private Paint paint;
    private Thread th;
    private boolean flag;
    private Canvas canvas;
    private int screenW, screenH;
    //定义两个矩形的宽高坐标
    private int x1 = 10, y1 = 110, w1 = 40, h1 = 40;
    private int x2 = 100, y2 = 110, w2 = 40, h2 = 40;
    //便于观察是否发生了碰撞设置一个标识位
    private boolean isCollsion;

    /**
     * SurfaceView初始化函数
     */
    public MySurfaceView(Context context) {
        super(context);
        sfh = this.getHolder();
        sfh.addCallback(this);
        paint = new Paint();
        paint.setColor(Color.WHITE);
        paint.setAntiAlias(true);
        setFocusable(true);
    }

    /**
     * SurfaceView视图创建，响应此函数
     */
    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        screenW = this.getWidth();
        screenH = this.getHeight();
        flag = true;
        //实例线程
        th = new Thread(this);
        //启动线程
        th.start();
    }

    /**
     * 游戏绘图
     */
    public void myDraw() {
        try {
            canvas = sfh.lockCanvas();
            if (canvas != null) {
                canvas.drawColor(Color.BLACK);
                if (isCollsion) {
                    paint.setColor(Color.RED);
                    paint.setTextSize(20);
                    canvas.drawText("Collision！", 0, 30, paint);
                } else {
                    paint.setColor(Color.WHITE);
                }
                //绘制两个矩形
                canvas.drawRect(x1, y1, x1 + w1, y1 + h1, paint);
                canvas.drawRect(x2, y2, x2 + w2, y2 + h2, paint);
            }
        } catch (Exception e) {
            // TODO: handle exception
        } finally {
            if (canvas != null)
                sfh.unlockCanvasAndPost(canvas);
        }
    }

    /**
     * 触屏事件监听
     */
    @Override
    public boolean onTouchEvent(MotionEvent event) {
        //让矩形1随着触屏位置移动
        x1 = (int) event.getX() - w1 / 2;
        y1 = (int) event.getY() - h1 / 2;
        if (isCollsionWithRect(x1, y1, w1, h1, x2, y2, w2, h2)) {
            isCollsion = true;
        } else {
            isCollsion = false;
        }
        return true;
    }

    /**
     * 按键事件监听
     */
    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        return super.onKeyDown(keyCode, event);
    }

    /**
     * 游戏逻辑
     */
    private void logic() {

    }

    public boolean isCollsionWithRect(int x1, int y1, int w1, int h1, int x2, int y2, int w2, int h2) {
        if (x1 >= x2 && x1 >= x2 + w2) {
            return false;
        } else if (x1 <= x2 && x1 + w1 <= x2) {
            return false;
        } else if (y1 >= y2 && y1 >= y2 + h2) {
            return false;
        } else if (y1 <= y2 && y1 + h1 <= y2) {
            return false;
        }
        return true;
    }

    @Override
    public void run() {
        while (flag) {
            long start = System.currentTimeMillis();
            myDraw();
            logic();
            long end = System.currentTimeMillis();
            try {
                if (end - start < 50) {
                    Thread.sleep(50 - (end - start));
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * SurfaceView视图状态发生改变，响应此函数
     */
    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
    }

    /**
     * SurfaceView视图消亡时，响应此函数
     */
    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        flag = false;
    }
}

圆形碰撞 代码:

public class MySurfaceView extends SurfaceView implements Callback, Runnable {
    private SurfaceHolder sfh;
    private Paint paint;
    private Thread th;
    private boolean flag;
    private Canvas canvas;
    private int screenW, screenH;
    //定义两个圆形的半径与坐标
    private int r1 = 20, r2 = 20;
    private int x1 = 50, y1 = 100, x2 = 150, y2 = 100;
    //定义一个碰撞标识位
    private boolean isCollision;

    /**
     * SurfaceView初始化函数
     */
    public MySurfaceView(Context context) {
        super(context);
        sfh = this.getHolder();
        sfh.addCallback(this);
        paint = new Paint();
        paint.setColor(Color.WHITE);
        paint.setAntiAlias(true);
        setFocusable(true);
    }

    /**
     * SurfaceView视图创建，响应此函数
     */
    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        screenW = this.getWidth();
        screenH = this.getHeight();
        flag = true;
        //实例线程
        th = new Thread(this);
        //启动线程
        th.start();
    }

    /**
     * 游戏绘图
     */
    public void myDraw() {
        try {
            canvas = sfh.lockCanvas();
            if (canvas != null) {
                canvas.drawColor(Color.BLACK);
                if (isCollision) {
                    paint.setColor(Color.RED);
                    paint.setTextSize(20);
                    canvas.drawText("Collision!", 0, 30, paint);
                } else {
                    paint.setColor(Color.WHITE);
                }
                canvas.drawCircle(x1, y1, r1, paint);
                canvas.drawCircle(x2, y2, r2, paint);
            }
        } catch (Exception e) {
            // TODO: handle exception
        } finally {
            if (canvas != null)
                sfh.unlockCanvasAndPost(canvas);
        }
    }

    /**
     * 触屏事件监听
     */
    @Override
    public boolean onTouchEvent(MotionEvent event) {
        x1 = (int) event.getX();
        y1 = (int) event.getY();
        if (isCollisionWithCircle(x1, y1, x2, y2, r1, r2)) {
            isCollision = true;
        } else {
            isCollision = false;
        }
        return true;
    }
    /**
     * 圆形碰撞
     * @param x1    圆形1的圆心X坐标
     * @param y1    圆形2的圆心X坐标
     * @param x2    圆形1的圆心Y坐标
     * @param y2    圆形2的圆心Y坐标
     * @param r1    圆形1的半径
     * @param r2    圆形2的半径
     * @return
     */
    private boolean isCollisionWithCircle(int x1, int y1, int x2, int y2, int r1, int r2) {
        //Math.sqrt:开平方
        //Math.pow(double x, double y): X的Y次方
        if (Math.sqrt(Math.pow(x1 - x2, 2) + Math.pow(y1 - y2, 2)) <= r1 + r2) {
            //如果两圆的圆心距小于或等于两圆半径则认为发生碰撞
            return true;
        }
        return false;
    }

    /**
     * 按键事件监听
     */
    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        return super.onKeyDown(keyCode, event);
    }

    /**
     * 游戏逻辑
     */
    private void logic() {
    }

    @Override
    public void run() {
        while (flag) {
            long start = System.currentTimeMillis();
            myDraw();
            logic();
            long end = System.currentTimeMillis();
            try {
                if (end - start < 50) {
                    Thread.sleep(50 - (end - start));
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * SurfaceView视图状态发生改变，响应此函数
     */
    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
    }

    /**
     * SurfaceView视图消亡时，响应此函数
     */
    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        flag = false;
    }
}

多矩形碰撞 代码

public class MySurfaceView extends SurfaceView implements Callback, Runnable {
    private SurfaceHolder sfh;
    private Paint paint;
    private Thread th;
    private boolean flag;
    private Canvas canvas;
    private int screenW, screenH;
    //定义两个矩形图形的宽高坐标
    private int rectX1 = 10, rectY1 = 10, rectW1 = 40, rectH1 = 40;
    private int rectX2 = 100, rectY2 = 110, rectW2 = 40, rectH2 = 40;
    //便于观察是否发生了碰撞设置一个标识位
    private boolean isCollsion;
    //定义第一个矩形的矩形碰撞数组
    private Rect clipRect1 = new Rect(0, 0, 15, 15);
    private Rect clipRect2 = new Rect(rectW1 - 15, rectH1 - 15, rectW1, rectH1);
    private Rect[] arrayRect1 = new Rect[] { clipRect1, clipRect2 };
    //定义第二个矩形的矩形碰撞数组
    private Rect clipRect3 = new Rect(0, 0, 15, 15);
    private Rect clipRect4 = new Rect(rectW2 - 15, rectH2 - 15, rectW2, rectH2);
    private Rect[] arrayRect2 = new Rect[] { clipRect3, clipRect4 };

    /**
     * SurfaceView初始化函数
     */
    public MySurfaceView(Context context) {
        super(context);
        sfh = this.getHolder();
        sfh.addCallback(this);
        paint = new Paint();
        paint.setColor(Color.WHITE);
        paint.setAntiAlias(true);
        setFocusable(true);
    }

    /**
     * SurfaceView视图创建，响应此函数
     */
    @Override
    public void surfaceCreated(SurfaceHolder holder) {
        screenW = this.getWidth();
        screenH = this.getHeight();
        flag = true;
        //实例线程
        th = new Thread(this);
        //启动线程
        th.start();
    }

    /**
     * 游戏绘图
     */
    public void myDraw() {
        try {
            canvas = sfh.lockCanvas();
            if (canvas != null) {
                canvas.drawColor(Color.BLACK);
                paint.setColor(Color.WHITE);
                paint.setStyle(Style.FILL);
                if (isCollsion) {
                    paint.setTextSize(20);
                    canvas.drawText("Collision！", 0, 30, paint);
                }
                //绘制两个矩形
                canvas.drawRect(rectX1, rectY1, rectX1 + rectW1, rectY1 + rectH1, paint);
                canvas.drawRect(rectX2, rectY2, rectX2 + rectW2, rectY2 + rectH2, paint);
                //---绘制碰撞区域使用非填充，并设置画笔颜色白色
                paint.setStyle(Style.STROKE);
                paint.setColor(Color.RED);
                //绘制第一个矩形的所有矩形碰撞区域
                for (int i = 0; i < arrayRect1.length; i++) {
                    canvas.drawRect(arrayRect1[i].left + this.rectX1, arrayRect1[i].top + this.rectY1, arrayRect1[i].right + this.rectX1, arrayRect1[i].bottom
                            + this.rectY1, paint);
                }
                //绘制第二个矩形的所有矩形碰撞区域
                for (int i = 0; i < arrayRect2.length; i++) {
                    canvas.drawRect(arrayRect2[i].left + this.rectX2, arrayRect2[i].top + this.rectY2, arrayRect2[i].right + this.rectX2, arrayRect2[i].bottom
                            + rectY2, paint);
                }
            }
        } catch (Exception e) {
            // TODO: handle exception
        } finally {
            if (canvas != null)
                sfh.unlockCanvasAndPost(canvas);
        }
    }

    /**
     * 触屏事件监听
     */
    @Override
    public boolean onTouchEvent(MotionEvent event) {
        //让矩形1随着触屏位置移动
        rectX1 = (int) event.getX() - rectW1 / 2;
        rectY1 = (int) event.getY() - rectH1 / 2;
        if (isCollsionWithRect(arrayRect1, arrayRect2)) {
            isCollsion = true;
        } else {
            isCollsion = false;
        }
        return true;
    }

    /**
     * 按键事件监听
     */
    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
        return super.onKeyDown(keyCode, event);
    }

    /**
     * 游戏逻辑
     */
    private void logic() {

    }

    //Rect 类中的四个属性  top bottom left right
    //分别表示这个矩形的         上       下            左          右
    public boolean isCollsionWithRect(Rect[] rectArray, Rect[] rect2Array) {
        Rect rect = null;
        Rect rect2 = null;
        for (int i = 0; i < rectArray.length; i++) {
            //依次取出第一个矩形数组的每个矩形实例
            rect = rectArray[i];
            //获取到第一个矩形数组中每个矩形元素的属性值
            int x1 = rect.left + this.rectX1;
            int y1 = rect.top + this.rectY1;
            int w1 = rect.right - rect.left;
            int h1 = rect.bottom - rect.top;
            for (int j = 0; j < rect2Array.length; j++) {
                //依次取出第二个矩形数组的每个矩形实例
                rect2 = rect2Array[j];
                //获取到第二个矩形数组中每个矩形元素的属性值
                int x2 = rect2.left + this.rectX2;
                int y2 = rect2.top + this.rectY2;
                int w2 = rect2.right - rect2.left;
                int h2 = rect2.bottom - rect2.top;
                //进行循环遍历两个矩形碰撞数组所有元素之间的位置关系
                if (x1 >= x2 && x1 >= x2 + w2) {
                } else if (x1 <= x2 && x1 + w1 <= x2) {
                } else if (y1 >= y2 && y1 >= y2 + h2) {
                } else if (y1 <= y2 && y1 + h1 <= y2) {
                } else {
                    //只要有一个碰撞矩形数组与另一碰撞矩形数组发生碰撞则认为碰撞
                    return true;
                }
            }
        }
        return false;
    }

    @Override
    public void run() {
        while (flag) {
            long start = System.currentTimeMillis();
            myDraw();
            logic();
            long end = System.currentTimeMillis();
            try {
                if (end - start < 50) {
                    Thread.sleep(50 - (end - start));
                }
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    /**
     * SurfaceView视图状态发生改变，响应此函数
     */
    @Override
    public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
    }

    /**
     * SurfaceView视图消亡时，响应此函数
     */
    @Override
    public void surfaceDestroyed(SurfaceHolder holder) {
        flag = false;
    }
}