private Standard.HRESULT _UpdateThumbnailClipping(bool attached)
 {
     Standard.RefRECT prcClip = null;
     if (attached && (this.ThumbnailClipMargin != _EmptyThickness))
     {
         Thickness     thumbnailClipMargin = this.ThumbnailClipMargin;
         Standard.RECT clientRect          = Standard.NativeMethods.GetClientRect(this._hwndSource.Handle);
         Rect          rect2 = Standard.DpiHelper.DeviceRectToLogical(new Rect((double)clientRect.Left, (double)clientRect.Top, (double)clientRect.Width, (double)clientRect.Height));
         if (((thumbnailClipMargin.Left + thumbnailClipMargin.Right) >= rect2.Width) || ((thumbnailClipMargin.Top + thumbnailClipMargin.Bottom) >= rect2.Height))
         {
             prcClip = new Standard.RefRECT(0, 0, 0, 0);
         }
         else
         {
             Rect logicalRectangle = new Rect(thumbnailClipMargin.Left, thumbnailClipMargin.Top, (rect2.Width - thumbnailClipMargin.Left) - thumbnailClipMargin.Right, (rect2.Height - thumbnailClipMargin.Top) - thumbnailClipMargin.Bottom);
             Rect rect4            = Standard.DpiHelper.LogicalRectToDevice(logicalRectangle);
             prcClip = new Standard.RefRECT((int)rect4.Left, (int)rect4.Top, (int)rect4.Right, (int)rect4.Bottom);
         }
     }
     return(this._taskbarList.SetThumbnailClip(this._hwndSource.Handle, prcClip));
 }
        private HRESULT _UpdateThumbnailClipping(bool attached)
        {
            Assert.IsNotNull(_window);

            RefRECT interopRc = null;
            if (attached && ThumbnailClipMargin != _EmptyThickness)
            {
                Thickness margin = ThumbnailClipMargin;
                // Use the native GetClientRect.  Window.ActualWidth and .ActualHeight include the non-client areas.
                RECT physicalClientRc = NativeMethods.GetClientRect(_hwndSource.Handle);
                Rect logicalClientRc = DpiHelper.DeviceRectToLogical(new Rect(physicalClientRc.Left, physicalClientRc.Top, physicalClientRc.Width, physicalClientRc.Height));

                // Crop the clipping to ensure that the margin doesn't overlap itself.
                if (margin.Left + margin.Right >= logicalClientRc.Width
                    || margin.Top + margin.Bottom >= logicalClientRc.Height)
                {
                    interopRc = new RefRECT(0, 0, 0, 0);
                }
                else
                {
                    Rect logicalClip = new Rect(margin.Left, margin.Top, logicalClientRc.Width - margin.Left - margin.Right, logicalClientRc.Height - margin.Top - margin.Bottom);
                    Rect physicalClip = DpiHelper.LogicalRectToDevice(logicalClip);
                    interopRc = new RefRECT((int)physicalClip.Left, (int)physicalClip.Top, (int)physicalClip.Right, (int)physicalClip.Bottom);
                }
            }

            // This will fail in the interop layer if called too early.
            HRESULT hr = _taskbarList.SetThumbnailClip(_hwndSource.Handle, interopRc);
            Assert.IsTrue(hr.Succeeded);
            return hr;
        }