android - Android imageview ジェスチャの回転により、エッジの品質が低下する

Question

以下のコードを使用して、画像ビュー内で画像をドラッグ、スケーリング、回転します。画像自体は同じ品質を維持しながら、画像の端を回転させるとぼやけてしまうという問題のみが正常に機能しています。これはスケーリングでは発生しません。解決策、タンク、コードを提案してください:-

private void dragZoomRotate(ImageView view, MotionEvent event){ 

    view.setScaleType(ImageView.ScaleType.MATRIX);  

    // Handle touch events here...

    switch (event.getAction() & MotionEvent.ACTION_MASK)   
    {
    case MotionEvent.ACTION_DOWN:
        savedMatrix.set(matrix);
        start.set(event.getX() , event.getY() );
        mode = DRAG;
        lastEvent = null;
        break;
    case MotionEvent.ACTION_POINTER_DOWN:   // first and second finger down
        oldDist = spacing(event);         
        savedMatrix.set(matrix);
        midPoint(mid, event);
        mode = ZOOM;

        lastEvent = new float[4];
        lastEvent[0] = event.getX(0);
        lastEvent[1] = event.getX(1);
        lastEvent[2] = event.getY(0);
        lastEvent[3] = event.getY(1);
        degrees = rotation(event);
        break;
    case MotionEvent.ACTION_UP: // first finger lifted
    case MotionEvent.ACTION_POINTER_UP:   // second finger lifted
        mode = NONE;
        lastEvent = null;

        break;
    case MotionEvent.ACTION_MOVE:    
        if (mode == DRAG) { 
            // ...
            matrix.set(savedMatrix);

            matrix.postTranslate(event.getX() - start.x , event.getY() - start.y );

        }
        else if (mode == ZOOM && event.getPointerCount()==2) {
            float newDist = spacing(event);
            matrix.set(savedMatrix);
            if (newDist > 10f) {              
                float scale = newDist / oldDist;
             //   matrix.postScale(scale, scale, mid.x, mid.y);
            } 
            if (lastEvent!=null){
                newRot = rotation(event); 
                float r = newRot-degrees;
                matrix.postRotate(r, view.getMeasuredWidth()/2, view.getMeasuredHeight()/2);  
            }
        }
        // 
        break;
    }   

    view.setImageMatrix(matrix);
}

private float rotation(MotionEvent event) 
{
    double delta_x = (event.getX(0) - event.getX(1));
    double delta_y = (event.getY(0) - event.getY(1)); 
    double radians = Math.atan2(delta_y, delta_x);
    return (float) Math.toDegrees(radians);         
} 




/*     
 * --------------------------------------------------------------------------
 * Method: spacing Parameters: MotionEvent Returns: float Description:
 * 
 * checks the spacing between the two fingers on touch
 * ----------------------------------------------------
 */

private float spacing(MotionEvent event) 
{
    float x = event.getX(0) - event.getX(1);
    float y = event.getY(0) - event.getY(1);
    return FloatMath.sqrt(x * x + y * y);
}

/*
 * --------------------------------------------------------------------------
 * Method: midPoint Parameters: PointF object, MotionEvent Returns: void
 * Description: calculates the midpoint between the two fingers
 * ------------------------------------------------------------
 */   

private void midPoint(PointF point, MotionEvent event) 
{
    float x = event.getX(0) + event.getX(1);
    float y = event.getY(0) + event.getY(1);
    point.set(x / 2, y / 2);
}