Android 基于矩阵将接触值转换为点

我正在按矩阵转换和缩放图像，现在我有了矩阵值。所以从矩阵值，我想把我的触摸坐标转换成它的位置，这是由矩阵得到的。那我该怎么办呢？ 请尽快帮助我

private void drawPoint(float x, float y, float pressure, float width) {

 // left is tx of matrix 
     // top is ty of matrix

    float curX = (x - left) / (scale * scale);
    float curY = (y - top) / (scale * scale);

         canvas.drawPoint((curX - left), (curY - top) , mPaint);
}

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我知道这是一个老帖子，但我也有同样的问题

我有一个应用矩阵变换的图像，首先我调整它的大小，然后我做一个转换

    image = new Matrix();
    image.setScale(zoom, zoom);

    Paint drawPaint = new Paint();
    drawPaint.setAntiAlias(true);
    drawPaint.setFilterBitmap(true);

    float centerScaledWidth = image_center.x * zoom / 2;
    float centerScaledHeigth = image_center.y * zoom / 2;

    image.postTranslate(screen_center.x -  centerScaledWidth, 
            screen_center.y - centerScaledHeigth);

    canvas.drawBitmap(bmp, image, drawPaint);

为了得到图像上的点，我得到了矩阵图像的轨迹，这是一种方法：

    @Override
    public boolean onTouchEvent(MotionEvent ev) {

            final int action = ev.getAction();

            switch (action & MotionEvent.ACTION_MASK) {

                    case MotionEvent.ACTION_DOWN: {

                        final float x = ev.getX();
                        final float y = ev.getY();

                        float[] pts = {x, y};

                        Matrix m = new Matrix();

                        // This is the magic, I set the new matrix m 
                        // as the inverse of 
                        // the matrix applied to the image
                        image.invert(m);

                        // transform the points using the inverse matrix
                        m.mapPoints(pts);

                        // do what you have to do
                        .......

                        Log.i("transformed", pts[0] +" "+pts[1]);

                        break;
                    }

            }

    return super.onTouchEvent(ev);
}

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这很有效，非常感谢。似乎你必须非常聪明才能在谷歌工作和为谷歌发展O