[PATCH v4 1/2] win32u: change the stretch mode of dst hdc from BlackOnWhite to ColorOnColor when using StretchBlt in TransparentBlt.

[yangkun]

From: yangkun

Signed-off-by: yangkun 
Change-Id: Ic3c64a5d2ffef7d890f461b089223fbd7a972ffd
---
 dlls/win32u/bitblt.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/dlls/win32u/bitblt.c b/dlls/win32u/bitblt.c
index a9f6f70daf6..d8c8aace7f0 100644
--- a/dlls/win32u/bitblt.c
+++ b/dlls/win32u/bitblt.c
@@ -857,6 +857,7 @@ BOOL WINAPI NtGdiTransparentBlt( HDC hdcDest, int xDest, int yDest, int widthDes
     int oldStretchMode;
     DIBSECTION dib;
     DC *dc_src;
+    DC *dc_work;

if(widthDest < 0 || heightDest < 0 || widthSrc < 0 || heightSrc < 0) {
         TRACE("Cannot mirror\n");
@@ -890,6 +891,11 @@ BOOL WINAPI NtGdiTransparentBlt( HDC hdcDest, int xDest, int yDest, int widthDes
     }
     else bmpWork = NtGdiCreateCompatibleBitmap( hdcDest, widthDest, heightDest );
     oldWork = NtGdiSelectBitmap(hdcWork, bmpWork);
+
+    if (!(dc_work = get_dc_ptr(hdcWork))) goto error;
+    dc_work->attr->stretch_blt_mode = COLORONCOLOR;
+    release_dc_ptr( dc_work );
+
     if (!NtGdiStretchBlt( hdcWork, 0, 0, widthDest, heightDest, hdcSrc, xSrc, ySrc,
                           widthSrc, heightSrc, SRCCOPY, 0 ))
     {
@@ -937,6 +943,7 @@ error:
     release_dc_ptr( dc_src );
     NtGdiGetAndSetDCDword( hdcDest, NtGdiSetBkColor, oldBackground, NULL );
     NtGdiGetAndSetDCDword( hdcDest, NtGdiSetTextColor, oldForeground, NULL );
+
     if(hdcWork) {
         NtGdiSelectBitmap(hdcWork, oldWork);
         NtGdiDeleteObjectApp( hdcWork );