tdf#91017 Enhance WMF import of EMR_ALPHABLEND action

The EMR_ALPHABLEND action was added 2012/2013, but missed support for
Bitmaps with Mask/Alpha. Due to that files with WMF containing these
actions may look different from before. Added suport to load contained
Mask/Alpha information in DIBs and the needed additional processing
through the display chain. WMF import is still based on Metafile
creation, when it would be using Primitives more original data could be
preserved.

Change-Id: I577569848cee2528328181fa0c7eb7f87857d094
Reviewed-on: https://gerrit.libreoffice.org/21709
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noelgrandin@gmail.com>
Reviewed-by: Armin Le Grand <Armin.Le.Grand@cib.de>

1 files changed, 37 insertions, 3 deletions

diff --git a/drawinglayer/source/processor2d/vclhelperbufferdevice.cxx b/drawinglayer/source/processor2d/vclhelperbufferdevice.cxx
index c9ef7ab24ad1..62d11c44673b 100644
--- a/drawinglayer/source/processor2d/vclhelperbufferdevice.cxx
+++ b/drawinglayer/source/processor2d/vclhelperbufferdevice.cxx
@@ -297,6 +297,9 @@ namespace drawinglayer
 
             // copy AA flag for new target
             mpContent->SetAntialiasing(mrOutDev.GetAntialiasing());
+
+            // copy RasterOp (e.g. may be ROP_XOR on destination)
+            mpContent->SetRasterOp(mrOutDev.GetRasterOp());
         }
     }
 
@@ -325,28 +328,50 @@ namespace drawinglayer
             const Point aEmptyPoint;
             const Size aSizePixel(maDestPixel.GetSize());
             const bool bWasEnabledDst(mrOutDev.IsMapModeEnabled());
+#ifdef DBG_UTIL
             static bool bDoSaveForVisualControl(false);
+#endif
 
             mrOutDev.EnableMapMode(false);
             mpContent->EnableMapMode(false);
             Bitmap aContent(mpContent->GetBitmap(aEmptyPoint, aSizePixel));
 
+#ifdef DBG_UTIL
             if(bDoSaveForVisualControl)
             {
-                SvFileStream aNew( "c:\\content.bmp", StreamMode::WRITE|StreamMode::TRUNC);
+                SvFileStream aNew(
+#ifdef WNT
+                    "c:\\content.bmp",
+#else
+                    "~/content.bmp",
+#endif
+                    StreamMode::WRITE|StreamMode::TRUNC);
                 WriteDIB(aContent, aNew, false, true);
             }
+#endif
+
+            // during painting the buffer, disable evtl. set RasterOp (may be ROP_XOR)
+            const RasterOp aOrigRasterOp(mrOutDev.GetRasterOp());
+            mrOutDev.SetRasterOp(ROP_OVERPAINT);
 
             if(mpAlpha)
             {
                 mpAlpha->EnableMapMode(false);
                 const AlphaMask aAlphaMask(mpAlpha->GetBitmap(aEmptyPoint, aSizePixel));
 
+#ifdef DBG_UTIL
                 if(bDoSaveForVisualControl)
                 {
-                    SvFileStream aNew( "c:\\transparence.bmp", StreamMode::WRITE|StreamMode::TRUNC);
+                    SvFileStream aNew(
+#ifdef WNT
+                        "c:\\transparence.bmp",
+#else
+                        "~/transparence.bmp",
+#endif
+                        StreamMode::WRITE|StreamMode::TRUNC);
                     WriteDIB(aAlphaMask.GetBitmap(), aNew, false, true);
                 }
+#endif
 
                 mrOutDev.DrawBitmapEx(maDestPixel.TopLeft(), BitmapEx(aContent, aAlphaMask));
             }
@@ -355,11 +380,19 @@ namespace drawinglayer
                 mpMask->EnableMapMode(false);
                 const Bitmap aMask(mpMask->GetBitmap(aEmptyPoint, aSizePixel));
 
+#ifdef DBG_UTIL
                 if(bDoSaveForVisualControl)
                 {
-                    SvFileStream aNew( "c:\\mask.bmp", StreamMode::WRITE|StreamMode::TRUNC);
+                    SvFileStream aNew(
+#ifdef WNT
+                        "c:\\mask.bmp",
+#else
+                        "~/mask.bmp",
+#endif
+                        StreamMode::WRITE|StreamMode::TRUNC);
                     WriteDIB(aMask, aNew, false, true);
                 }
+#endif
 
                 mrOutDev.DrawBitmapEx(maDestPixel.TopLeft(), BitmapEx(aContent, aMask));
             }
@@ -374,6 +407,7 @@ namespace drawinglayer
                 mrOutDev.DrawBitmap(maDestPixel.TopLeft(), aContent);
             }
 
+            mrOutDev.SetRasterOp(aOrigRasterOp);
             mrOutDev.EnableMapMode(bWasEnabledDst);
         }
     }