[Spice-devel] [PATCH qxl-wddm-dod] Implements screen to screen move correctly

[Frediano Ziglio]

Doing some fast check on Windows 8.1 you could note that
moving windows you got a weird effect were windows were a
bit misaligned.
As documented in DXGKARG_PRESENT_DISPLAYONLY page
NumMoves/pMoves fields point to an array of screen-to-screen
moves while our code implemented them as an image drawing
(the same implementation of dirty rects) causing the weird
effect mentioned.
This patch implement the moves using QXL_COPY_BITS operation
instead of a QXL_DRAW_COPY fixing the issue and avoiding sending
image to the server making the move/scroll operations on the
guest faster (and taking less bandwidth).
It seems that Windows 10 doesn't send the move commands but
instead send only dirty rects so you can't note this problem
using Windows 10.

Signed-off-by: Frediano Ziglio <fziglio at redhat.com>
---
 qxldod/QxlDod.cpp | 26 +++++++++++++++++++++-----
 qxldod/QxlDod.h   |  1 +
 2 files changed, 22 insertions(+), 5 deletions(-)

diff --git a/qxldod/QxlDod.cpp b/qxldod/QxlDod.cpp
index 68e3383..7adbec4 100755
--- a/qxldod/QxlDod.cpp
+++ b/qxldod/QxlDod.cpp
@@ -3738,11 +3738,7 @@ QxlDevice::ExecutePresentDisplayOnly(
         DbgPrint(TRACE_LEVEL_INFORMATION, ("--- %d SourcePoint.x = %ld, SourcePoint.y = %ld, DestRect.bottom = %ld, DestRect.left = %ld, DestRect.right = %ld, DestRect.top = %ld\n", 
             i , pSourcePoint->x, pSourcePoint->y, pDestRect->bottom, pDestRect->left, pDestRect->right, pDestRect->top));
 
-        BltBits(&DstBltInfo,
-        &SrcBltInfo,
-        1,
-        pDestRect,
-        pSourcePoint);
+        CopyBits(*pDestRect, *pSourcePoint);
     }
 
     // Copy all the dirty rects from source image to video frame buffer.
@@ -4184,6 +4180,26 @@ VOID QxlDevice::SetImageId(InternalImage *internal,
     }
 }
 
+void QxlDevice::CopyBits(const RECT& rect, const POINT& sourcePoint)
+{
+    PAGED_CODE();
+    QXLDrawable *drawable;
+
+    DbgPrint(TRACE_LEVEL_VERBOSE, ("---> %s device %d\n", __FUNCTION__,m_Id));
+
+    if (!(drawable = Drawable(QXL_COPY_BITS, &rect, NULL, 0))) {
+        DbgPrint(TRACE_LEVEL_ERROR, ("Cannot get Drawable.\n"));
+        return;
+    }
+
+    drawable->u.copy_bits.src_pos.x = sourcePoint.x;
+    drawable->u.copy_bits.src_pos.y = sourcePoint.y;
+
+    PushDrawable(drawable);
+
+    DbgPrint(TRACE_LEVEL_VERBOSE, ("<--- %s\n", __FUNCTION__));
+}
+
 VOID QxlDevice::BltBits (
     BLT_INFO* pDst,
     CONST BLT_INFO* pSrc,
diff --git a/qxldod/QxlDod.h b/qxldod/QxlDod.h
index b151484..324c3d6 100755
--- a/qxldod/QxlDod.h
+++ b/qxldod/QxlDod.h
@@ -487,6 +487,7 @@ protected:
                     UINT  NumRects,
                     _In_reads_(NumRects) CONST RECT *pRects,
                     POINT*   pSourcePoint);
+    void QxlDevice::CopyBits(const RECT& rect, const POINT& sourcePoint);
     QXLDrawable *Drawable(UINT8 type,
                     CONST RECT *area,
                     CONST RECT *clip,
-- 
2.9.3