drop mask from BitmapEx

So that we have fewer cases to deal with when we transition to
32-bit bitmaps.

(*) rename maMask to maAlphaMask, since now it is only being used
for alpha duties.
(*) drop mbAlpha and mbTransparent to simplify state management,
the only thing we need to check for alpha is if maAlphaMask is
non-empty.

Change-Id: I06252e38e950e846a94b4c2ba8ea763be17801fe
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/111679
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

11 files changed, 45 insertions, 108 deletions

diff --git a/vcl/source/gdi/gdimetafiletools.cxx b/vcl/source/gdi/gdimetafiletools.cxx
index e0b96a6ba5ce..9b3e26afb331 100644
--- a/vcl/source/gdi/gdimetafiletools.cxx
+++ b/vcl/source/gdi/gdimetafiletools.cxx
@@ -171,7 +171,7 @@ namespace
         aVDev->SetFillColor( COL_WHITE);
         aVDev->SetLineColor();
 
-        if(rBitmapEx.IsTransparent())
+        if(rBitmapEx.IsAlpha())
         {
             // use given alpha channel
             aVDev->DrawBitmap(Point(0, 0), rBitmapEx.GetAlpha().GetBitmap());
diff --git a/vcl/source/gdi/gdimtf.cxx b/vcl/source/gdi/gdimtf.cxx
index 2856ecaed18e..a31f8e768ece 100644
--- a/vcl/source/gdi/gdimtf.cxx
+++ b/vcl/source/gdi/gdimtf.cxx
@@ -1780,8 +1780,6 @@ BitmapEx GDIMetaFile::ImplBmpMonoFnc( const BitmapEx& rBmpEx, const void* pBmpPa
 
     if( rBmpEx.IsAlpha() )
         return BitmapEx( aBmp, rBmpEx.GetAlpha() );
-    else if( rBmpEx.IsTransparent() )
-        return BitmapEx( aBmp, rBmpEx.GetMask() );
     else
         return BitmapEx( aBmp );
 }
diff --git a/vcl/source/gdi/impgraph.cxx b/vcl/source/gdi/impgraph.cxx
index b06423adbe3e..91f2bca31189 100644
--- a/vcl/source/gdi/impgraph.cxx
+++ b/vcl/source/gdi/impgraph.cxx
@@ -466,7 +466,7 @@ bool ImpGraphic::isTransparent() const
     }
     else if (meType == GraphicType::Bitmap && !maVectorGraphicData)
     {
-        bRet = mpAnimation ? mpAnimation->IsTransparent() : maBitmapEx.IsTransparent();
+        bRet = mpAnimation ? mpAnimation->IsTransparent() : maBitmapEx.IsAlpha();
     }
 
     return bRet;
@@ -741,7 +741,7 @@ const GDIMetaFile& ImpGraphic::getGDIMetaFile() const
 
         // #123983# directly create a metafile with the same PrefSize and PrefMapMode
         // the bitmap has, this will be an always correct metafile
-        if(maBitmapEx.IsTransparent())
+        if(maBitmapEx.IsAlpha())
         {
             pThat->maMetaFile.AddAction(new MetaBmpExScaleAction(Point(), maBitmapEx.GetPrefSize(), maBitmapEx));
         }
diff --git a/vcl/source/gdi/mtfxmldump.cxx b/vcl/source/gdi/mtfxmldump.cxx
index 373eb2b20a69..d612898e6c8c 100644
--- a/vcl/source/gdi/mtfxmldump.cxx
+++ b/vcl/source/gdi/mtfxmldump.cxx
@@ -331,14 +331,12 @@ OString convertLineStyleToString(const MetaActionType nActionType)
     return "";
 }
 
-OUString convertBitmapExTransparentType(TransparentType eType)
+OUString convertBitmapExTransparentType(BitmapEx const & rBitmapEx)
 {
-    switch (eType)
-    {
-        default:
-        case TransparentType::NONE:   return "none";
-        case TransparentType::Bitmap: return "bitmap";
-    }
+    if (rBitmapEx.IsAlpha())
+        return "bitmap";
+    else
+        return "none";
 }
 
 OUString convertMapUnitToString(MapUnit eUnit)
@@ -856,7 +854,7 @@ void MetafileXmlDump::writeXml(const GDIMetaFile& rMetaFile, tools::XmlWriter& r
                 rWriter.startElement(sCurrentElementTag);
                 writePoint(rWriter, pMeta->GetPoint());
                 rWriter.attribute("crc", hex32(pMeta->GetBitmapEx().GetBitmap().GetChecksum()));
-                rWriter.attribute("transparenttype", convertBitmapExTransparentType(pMeta->GetBitmapEx().GetTransparentType()));
+                rWriter.attribute("transparenttype", convertBitmapExTransparentType(pMeta->GetBitmapEx()));
                 rWriter.endElement();
             }
             break;
@@ -868,7 +866,7 @@ void MetafileXmlDump::writeXml(const GDIMetaFile& rMetaFile, tools::XmlWriter& r
                 writePoint(rWriter, pMeta->GetPoint());
                 writeSize(rWriter, pMeta->GetSize());
                 rWriter.attribute("crc", hex32(pMeta->GetBitmapEx().GetBitmap().GetChecksum()));
-                rWriter.attribute("transparenttype", convertBitmapExTransparentType(pMeta->GetBitmapEx().GetTransparentType()));
+                rWriter.attribute("transparenttype", convertBitmapExTransparentType(pMeta->GetBitmapEx()));
                 rWriter.endElement();
             }
             break;
@@ -886,7 +884,7 @@ void MetafileXmlDump::writeXml(const GDIMetaFile& rMetaFile, tools::XmlWriter& r
                 rWriter.attribute("srcwidth", pMeta->GetSrcSize().Width());
                 rWriter.attribute("srcheight", pMeta->GetSrcSize().Height());
                 rWriter.attribute("crc", hex32(pMeta->GetBitmapEx().GetBitmap().GetChecksum()));
-                rWriter.attribute("transparenttype", convertBitmapExTransparentType(pMeta->GetBitmapEx().GetTransparentType()));
+                rWriter.attribute("transparenttype", convertBitmapExTransparentType(pMeta->GetBitmapEx()));
                 rWriter.endElement();
             }
             break;
@@ -1002,7 +1000,7 @@ void MetafileXmlDump::writeXml(const GDIMetaFile& rMetaFile, tools::XmlWriter& r
                     rWriter.startElement("bitmap");
                     BitmapEx const & rBitmapEx = rWallpaper.GetBitmap();
                     rWriter.attribute("crc", hex32(rBitmapEx.GetChecksum()));
-                    rWriter.attribute("transparenttype", convertBitmapExTransparentType(rBitmapEx.GetTransparentType()));
+                    rWriter.attribute("transparenttype", convertBitmapExTransparentType(rBitmapEx));
                     rWriter.attribute("pixelformat", convertPixelFormatToString(rBitmapEx.GetBitmap().getPixelFormat()));
                     rWriter.attribute("width", hex32(rBitmapEx.GetSizePixel().Width()));
                     rWriter.attribute("height", hex32(rBitmapEx.GetSizePixel().Height()));
diff --git a/vcl/source/gdi/pdfextoutdevdata.cxx b/vcl/source/gdi/pdfextoutdevdata.cxx
index fc431c7e65a2..96a77a15d94d 100644
--- a/vcl/source/gdi/pdfextoutdevdata.cxx
+++ b/vcl/source/gdi/pdfextoutdevdata.cxx
@@ -451,12 +451,11 @@ bool PageSyncData::PlaySyncPageAct( PDFWriter& rWriter, sal_uInt32& rCurGDIMtfAc
                             rWriter.SetClipRegion( aRect);
                         }
 
-                        Bitmap aMask;
+                        AlphaMask aAlphaMask;
                         if (nTransparency)
                         {
-                            AlphaMask aAlphaMask(aGraphic.GetSizePixel());
+                            aAlphaMask = AlphaMask(aGraphic.GetSizePixel());
                             aAlphaMask.Erase(nTransparency);
-                            aMask = aAlphaMask.GetBitmap();
                         }
 
                         SvMemoryStream aTmp;
@@ -483,7 +482,7 @@ bool PageSyncData::PlaySyncPageAct( PDFWriter& rWriter, sal_uInt32& rCurGDIMtfAc
                                 }
                             }
                             auto ePixelFormat = aGraphic.GetBitmapEx().getPixelFormat();
-                            rWriter.DrawJPGBitmap(aTmp, ePixelFormat > vcl::PixelFormat::N8_BPP, aGraphic.GetSizePixel(), aOutputRect, aMask, aGraphic);
+                            rWriter.DrawJPGBitmap(aTmp, ePixelFormat > vcl::PixelFormat::N8_BPP, aGraphic.GetSizePixel(), aOutputRect, aAlphaMask, aGraphic);
                         }
 
                         if ( bClippingNeeded )
diff --git a/vcl/source/gdi/pdfwriter.cxx b/vcl/source/gdi/pdfwriter.cxx
index ab7a03cb205c..53609379bca8 100644
--- a/vcl/source/gdi/pdfwriter.cxx
+++ b/vcl/source/gdi/pdfwriter.cxx
@@ -323,9 +323,9 @@ void PDFWriter::SetTextAlign( ::TextAlign eAlign )
     xImplementation->setTextAlign( eAlign );
 }
 
-void PDFWriter::DrawJPGBitmap( SvStream& rStreamData, bool bIsTrueColor, const Size& rSrcSizePixel, const tools::Rectangle& rTargetArea, const Bitmap& rMask, const Graphic& rGraphic )
+void PDFWriter::DrawJPGBitmap( SvStream& rStreamData, bool bIsTrueColor, const Size& rSrcSizePixel, const tools::Rectangle& rTargetArea, const AlphaMask& rAlphaMask, const Graphic& rGraphic )
 {
-    xImplementation->drawJPGBitmap( rStreamData, bIsTrueColor, rSrcSizePixel, rTargetArea, rMask, rGraphic );
+    xImplementation->drawJPGBitmap( rStreamData, bIsTrueColor, rSrcSizePixel, rTargetArea, rAlphaMask, rGraphic );
 }
 
 sal_Int32 PDFWriter::CreateLink( const tools::Rectangle& rRect, sal_Int32 nPageNr )
diff --git a/vcl/source/gdi/pdfwriter_impl.cxx b/vcl/source/gdi/pdfwriter_impl.cxx
index ad9c1e0935e4..99918b8df1b1 100644
--- a/vcl/source/gdi/pdfwriter_impl.cxx
+++ b/vcl/source/gdi/pdfwriter_impl.cxx
@@ -1735,7 +1735,7 @@ void PDFWriterImpl::endPage()
         {
             writeJPG( jpeg );
             jpeg.m_pStream.reset();
-            jpeg.m_aMask = Bitmap();
+            jpeg.m_aAlphaMask = AlphaMask();
         }
     }
     for (auto & item : m_aTransparentObjects)
@@ -8368,12 +8368,10 @@ void PDFWriterImpl::writeJPG( JPGEmit& rObject )
     rObject.m_pStream->Seek( STREAM_SEEK_TO_BEGIN );
 
     sal_Int32 nMaskObject = 0;
-    if( !rObject.m_aMask.IsEmpty() )
+    if( !rObject.m_aAlphaMask.IsEmpty() )
     {
-        if (rObject.m_aMask.getPixelFormat() == vcl::PixelFormat::N1_BPP
-            || (rObject.m_aMask.getPixelFormat() == vcl::PixelFormat::N8_BPP
-                && m_aContext.Version >= PDFWriter::PDFVersion::PDF_1_4
-                && !m_bIsPDF_A1))
+        if (m_aContext.Version >= PDFWriter::PDFVersion::PDF_1_4
+                && !m_bIsPDF_A1)
         {
             nMaskObject = createObject();
         }
@@ -8404,7 +8402,7 @@ void PDFWriterImpl::writeJPG( JPGEmit& rObject )
     aLine.append( nLength );
     if( nMaskObject )
     {
-        aLine.append(rObject.m_aMask.getPixelFormat() == vcl::PixelFormat::N1_BPP ? " /Mask " : " /SMask ");
+        aLine.append(" /SMask ");
         aLine.append( nMaskObject );
         aLine.append( " 0 R " );
     }
@@ -8423,10 +8421,7 @@ void PDFWriterImpl::writeJPG( JPGEmit& rObject )
     {
         BitmapEmit aEmit;
         aEmit.m_nObject = nMaskObject;
-        if (rObject.m_aMask.getPixelFormat() == vcl::PixelFormat::N1_BPP)
-            aEmit.m_aBitmap = BitmapEx( rObject.m_aMask, rObject.m_aMask );
-        else if(rObject.m_aMask.getPixelFormat() == vcl::PixelFormat::N8_BPP)
-            aEmit.m_aBitmap = BitmapEx( rObject.m_aMask, AlphaMask( rObject.m_aMask ) );
+        aEmit.m_aBitmap = BitmapEx( rObject.m_aAlphaMask, rObject.m_aAlphaMask );
         writeBitmapObject( aEmit, true );
     }
 
@@ -8708,23 +8703,12 @@ bool PDFWriterImpl::writeBitmapObject( BitmapEmit& rObject, bool bMask )
                 bWriteMask = true;
             // else draw without alpha channel
         }
-        else
-        {
-            switch( rObject.m_aBitmap.GetTransparentType() )
-            {
-                case TransparentType::NONE:
-                    break;
-                case TransparentType::Bitmap:
-                    bWriteMask = true;
-                    break;
-            }
-        }
     }
     else
     {
         if( m_aContext.Version < PDFWriter::PDFVersion::PDF_1_4 || ! rObject.m_aBitmap.IsAlpha() )
         {
-            aBitmap = getExportBitmap(rObject.m_aBitmap.GetMask());
+            aBitmap = getExportBitmap(rObject.m_aBitmap.GetAlpha());
             aBitmap.Convert( BmpConversion::N1BitThreshold );
             SAL_WARN_IF(aBitmap.getPixelFormat() != vcl::PixelFormat::N1_BPP, "vcl.pdfwriter", "mask conversion failed" );
         }
@@ -9003,7 +8987,7 @@ void PDFWriterImpl::createEmbeddedFile(const Graphic& rGraphic, ReferenceXObject
     rEmit.m_aPixelSize = rGraphic.GetPrefSize();
 }
 
-void PDFWriterImpl::drawJPGBitmap( SvStream& rDCTData, bool bIsTrueColor, const Size& rSizePixel, const tools::Rectangle& rTargetArea, const Bitmap& rMask, const Graphic& rGraphic )
+void PDFWriterImpl::drawJPGBitmap( SvStream& rDCTData, bool bIsTrueColor, const Size& rSizePixel, const tools::Rectangle& rTargetArea, const AlphaMask& rAlphaMask, const Graphic& rGraphic )
 {
     MARK( "drawJPGBitmap" );
 
@@ -9023,10 +9007,10 @@ void PDFWriterImpl::drawJPGBitmap( SvStream& rDCTData, bool bIsTrueColor, const
         // load stream to bitmap and draw the bitmap instead
         Graphic aGraphic;
         GraphicConverter::Import( rDCTData, aGraphic, ConvertDataFormat::JPG );
-        if( !rMask.IsEmpty() && rMask.GetSizePixel() == aGraphic.GetSizePixel() )
+        if( !rAlphaMask.IsEmpty() && rAlphaMask.GetSizePixel() == aGraphic.GetSizePixel() )
         {
             Bitmap aBmp( aGraphic.GetBitmapEx().GetBitmap() );
-            BitmapEx aBmpEx( aBmp, rMask );
+            BitmapEx aBmpEx( aBmp, rAlphaMask );
             drawBitmap( rTargetArea.TopLeft(), rTargetArea.GetSize(), aBmpEx );
         }
         else
@@ -9043,8 +9027,8 @@ void PDFWriterImpl::drawJPGBitmap( SvStream& rDCTData, bool bIsTrueColor, const
     aID.m_nSize         = pStream->Tell();
     pStream->Seek( STREAM_SEEK_TO_BEGIN );
     aID.m_nChecksum     = vcl_get_checksum( 0, pStream->GetData(), aID.m_nSize );
-    if( ! rMask.IsEmpty() )
-        aID.m_nMaskChecksum = rMask.GetChecksum();
+    if( ! rAlphaMask.IsEmpty() )
+        aID.m_nMaskChecksum = rAlphaMask.GetChecksum();
 
     std::vector< JPGEmit >::const_iterator it = std::find_if(m_aJPGs.begin(), m_aJPGs.end(),
                                              [&](const JPGEmit& arg) { return aID == arg.m_aID; });
@@ -9057,8 +9041,8 @@ void PDFWriterImpl::drawJPGBitmap( SvStream& rDCTData, bool bIsTrueColor, const
         rEmit.m_aID         = aID;
         rEmit.m_pStream = std::move( pStream );
         rEmit.m_bTrueColor  = bIsTrueColor;
-        if( !rMask.IsEmpty() && rMask.GetSizePixel() == rSizePixel )
-            rEmit.m_aMask   = rMask;
+        if( !rAlphaMask.IsEmpty() && rAlphaMask.GetSizePixel() == rSizePixel )
+            rEmit.m_aAlphaMask = rAlphaMask;
         createEmbeddedFile(rGraphic, rEmit.m_aReferenceXObject, rEmit.m_nObject);
 
         it = m_aJPGs.begin();
@@ -9140,12 +9124,6 @@ const BitmapEmit& PDFWriterImpl::createBitmapEmit( const BitmapEx& i_rBitmap, co
     aID.m_nMaskChecksum     = 0;
     if( aBitmap.IsAlpha() )
         aID.m_nMaskChecksum = aBitmap.GetAlpha().GetChecksum();
-    else
-    {
-        Bitmap aMask = aBitmap.GetMask();
-        if( ! aMask.IsEmpty() )
-            aID.m_nMaskChecksum = aMask.GetChecksum();
-    }
     std::list< BitmapEmit >::const_iterator it = std::find_if(m_aBitmaps.begin(), m_aBitmaps.end(),
                                              [&](const BitmapEmit& arg) { return aID == arg.m_aID; });
     if( it == m_aBitmaps.end() )
@@ -9412,7 +9390,7 @@ void PDFWriterImpl::drawWallpaper( const tools::Rectangle& rRect, const Wallpape
             bDrawBitmap = true;
         }
 
-        if( aBitmap.IsTransparent() )
+        if( aBitmap.IsAlpha() )
         {
             if( rWall.IsGradient() )
                 bDrawGradient = true;
diff --git a/vcl/source/gdi/pdfwriter_impl.hxx b/vcl/source/gdi/pdfwriter_impl.hxx
index 6280fc5ec11f..d49add8e8f71 100644
--- a/vcl/source/gdi/pdfwriter_impl.hxx
+++ b/vcl/source/gdi/pdfwriter_impl.hxx
@@ -230,7 +230,7 @@ struct JPGEmit
     BitmapID            m_aID;
     std::unique_ptr<SvMemoryStream>
                         m_pStream;
-    Bitmap              m_aMask;
+    AlphaMask           m_aAlphaMask;
     sal_Int32           m_nObject;
     bool                m_bTrueColor;
     ReferenceXObjectEmit m_aReferenceXObject;
@@ -1204,7 +1204,7 @@ public:
 
     void drawBitmap( const Point& rDestPoint, const Size& rDestSize, const Bitmap& rBitmap, const Graphic& rGraphic );
     void drawBitmap( const Point& rDestPoint, const Size& rDestSize, const BitmapEx& rBitmap );
-    void drawJPGBitmap( SvStream& rDCTData, bool bIsTrueColor, const Size& rSizePixel, const tools::Rectangle& rTargetArea, const Bitmap& rMask, const Graphic& rGraphic );
+    void drawJPGBitmap( SvStream& rDCTData, bool bIsTrueColor, const Size& rSizePixel, const tools::Rectangle& rTargetArea, const AlphaMask& rAlphaMask, const Graphic& rGraphic );
     /// Stores the original PDF data from rGraphic as an embedded file.
     void createEmbeddedFile(const Graphic& rGraphic, ReferenceXObjectEmit& rEmit, sal_Int32 nBitmapObject);
 
diff --git a/vcl/source/gdi/pdfwriter_impl2.cxx b/vcl/source/gdi/pdfwriter_impl2.cxx
index a0a4fb828995..878915e650c7 100644
--- a/vcl/source/gdi/pdfwriter_impl2.cxx
+++ b/vcl/source/gdi/pdfwriter_impl2.cxx
@@ -172,21 +172,21 @@ void PDFWriterImpl::implWriteBitmapEx( const Point& i_rPoint, const Size& i_rSiz
         bUseJPGCompression = false;
 
     auto   pStrm=std::make_shared<SvMemoryStream>();
-    Bitmap aMask;
+    AlphaMask aAlphaMask;
 
     bool bTrueColorJPG = true;
     if ( bUseJPGCompression )
     {
         // TODO this checks could be done much earlier, saving us
         // from trying conversion & stores before...
-        if ( !aBitmapEx.IsTransparent() )
+        if ( !aBitmapEx.IsAlpha() )
         {
             const auto& rCacheEntry=m_aPDFBmpCache.find(
                 aBitmapEx.GetChecksum());
             if ( rCacheEntry != m_aPDFBmpCache.end() )
             {
                 m_rOuterFace.DrawJPGBitmap( *rCacheEntry->second, true, aSizePixel,
-                                            tools::Rectangle( aPoint, aSize ), aMask, i_Graphic );
+                                            tools::Rectangle( aPoint, aSize ), aAlphaMask, i_Graphic );
                 return;
             }
         }
@@ -199,13 +199,8 @@ void PDFWriterImpl::implWriteBitmapEx( const Point& i_rPoint, const Size& i_rSiz
             WriteDIBBitmapEx(aBitmapEx, aTemp); // is capable of zlib stream compression
             nZippedFileSize = aTemp.TellEnd();
         }
-        if ( aBitmapEx.IsTransparent() )
-        {
-            if ( aBitmapEx.IsAlpha() )
-                aMask = aBitmapEx.GetAlpha().GetBitmap();
-            else
-                aMask = aBitmapEx.GetMask();
-        }
+        if ( aBitmapEx.IsAlpha() )
+            aAlphaMask = aBitmapEx.GetAlpha();
         Graphic aGraphic(BitmapEx(aBitmapEx.GetBitmap()));
 
         Sequence< PropertyValue > aFilterData( 2 );
@@ -261,15 +256,15 @@ void PDFWriterImpl::implWriteBitmapEx( const Point& i_rPoint, const Size& i_rSiz
     }
     if ( bUseJPGCompression )
     {
-        m_rOuterFace.DrawJPGBitmap( *pStrm, bTrueColorJPG, aSizePixel, tools::Rectangle( aPoint, aSize ), aMask, i_Graphic );
-        if (!aBitmapEx.IsTransparent() && bTrueColorJPG)
+        m_rOuterFace.DrawJPGBitmap( *pStrm, bTrueColorJPG, aSizePixel, tools::Rectangle( aPoint, aSize ), aAlphaMask, i_Graphic );
+        if (!aBitmapEx.IsAlpha() && bTrueColorJPG)
         {
             // Cache last jpeg export
             m_aPDFBmpCache.insert(
                 {aBitmapEx.GetChecksum(), pStrm});
         }
     }
-    else if ( aBitmapEx.IsTransparent() )
+    else if ( aBitmapEx.IsAlpha() )
         m_rOuterFace.DrawBitmapEx( aPoint, aSize, aBitmapEx );
     else
         m_rOuterFace.DrawBitmap( aPoint, aSize, aBitmapEx.GetBitmap(), i_Graphic );
diff --git a/vcl/source/gdi/print.cxx b/vcl/source/gdi/print.cxx
index e88592f225a5..d7928956e9bd 100644
--- a/vcl/source/gdi/print.cxx
+++ b/vcl/source/gdi/print.cxx
@@ -307,9 +307,8 @@ void Printer::DrawDeviceBitmap( const Point& rDestPt, const Size& rDestSize,
     }
     else
     {
-        Bitmap aBmp( rBmpEx.GetBitmap() ), aMask( rBmpEx.GetMask() );
-        aBmp.Replace( aMask, COL_WHITE );
-        ImplPrintTransparent( aBmp, aMask, rDestPt, rDestSize, rSrcPtPixel, rSrcSizePixel );
+        Bitmap aBmp( rBmpEx.GetBitmap() );
+        ImplPrintTransparent( aBmp, Bitmap(), rDestPt, rDestSize, rSrcPtPixel, rSrcSizePixel );
     }
 }
 
diff --git a/vcl/source/gdi/print2.cxx b/vcl/source/gdi/print2.cxx
index f7e4d8875341..3526d9017cb5 100644
--- a/vcl/source/gdi/print2.cxx
+++ b/vcl/source/gdi/print2.cxx
@@ -186,37 +186,7 @@ void ImplConvertTransparentAction( GDIMetaFile&        o_rMtf,
         }
 
         Bitmap aBmp(aBmpEx.GetBitmap());
-        if (!aBmpEx.IsAlpha())
-        {
-            // blend with mask
-            Bitmap::ScopedReadAccess pRA(aBmp);
-
-            if (!pRA)
-                return; // what else should I do?
-
-            Color aActualColor(aBgColor);
-
-            if (pRA->HasPalette())
-                aActualColor = pRA->GetBestPaletteColor(aBgColor);
-
-            pRA.reset();
-
-            // did we get true white?
-            if (aActualColor.GetColorError(aBgColor))
-            {
-                // no, create truecolor bitmap, then
-                aBmp.Convert(BmpConversion::N24Bit);
-
-                // fill masked out areas white
-                aBmp.Replace(aBmpEx.GetMask(), aBgColor);
-            }
-            else
-            {
-                // fill masked out areas white
-                aBmp.Replace(aBmpEx.GetMask(), aActualColor);
-            }
-        }
-        else
+        if (aBmpEx.IsAlpha())
         {
             // blend with alpha channel
             aBmp.Convert(BmpConversion::N24Bit);