Make BitmapColor inherit from / merge into Color

BitmapColor itself is kept to distingish the Color usage as part
of a color palette, which continues to store the offset in the
blue value. The original special mbIndex handling is long gone
since commit 1fefdd6f3b41 ("Alpha channel in BitmapColor - change
bIndex to alpha"), so there is no data difference.

This also results in the following changes:

* now has a basic_ostream<charT, traits>& operator<<
(that was my actual starting point... for an other bug fix)
* there is a minimal difference for GetLiminance
BGR(29,151,76) => BGR(28,151,77)
* no more return values for Merge and Invert
(previously returning *this)
* replaces all GetBlueOrIndex with GetIndex

This leaves one "problematic" part: the GetColorError handling.
At first glance it should probably be virtual. The Color variant
is less strict then the BitmapColor one - for whatever reason.
BitmapColor is always used to search for the best match in a
Palette. Currently I'm simply leaving both variants. Would be
nice to have an explict for functions here.

Change-Id: I251ba3024a1d60f2a9d9fde9cd0a60f08e8322a7
Reviewed-on: https://gerrit.libreoffice.org/72181
Tested-by: Jenkins
Reviewed-by: Tomaž Vajngerl <quikee@gmail.com>
Reviewed-by: Jan-Marek Glogowski <glogow@fbihome.de>

14 files changed, 44 insertions, 42 deletions

diff --git a/vcl/source/bitmap/BitmapLightenFilter.cxx b/vcl/source/bitmap/BitmapLightenFilter.cxx
index 52e41ae33e97..45013b143783 100644
--- a/vcl/source/bitmap/BitmapLightenFilter.cxx
+++ b/vcl/source/bitmap/BitmapLightenFilter.cxx
@@ -37,7 +37,8 @@ BitmapEx BitmapLightenFilter::execute(BitmapEx const& rBitmapEx) const
                     = pRead->HasPalette()
                           ? pRead->GetPaletteColor(pRead->GetIndexFromData(pScanlineRead, nX))
                           : pRead->GetPixelFromData(pScanlineRead, nX);
-                basegfx::BColor aBColor(aBmpColor.Invert().GetColor().getBColor());
+                aBmpColor.Invert();
+                basegfx::BColor aBColor(aBmpColor.getBColor());
                 aBColor = basegfx::utils::rgb2hsl(aBColor);
 
                 double fHue = aBColor.getRed();
diff --git a/vcl/source/bitmap/BitmapSolarizeFilter.cxx b/vcl/source/bitmap/BitmapSolarizeFilter.cxx
index d12986c81c9f..179868aa5e2d 100644
--- a/vcl/source/bitmap/BitmapSolarizeFilter.cxx
+++ b/vcl/source/bitmap/BitmapSolarizeFilter.cxx
@@ -32,7 +32,8 @@ BitmapEx BitmapSolarizeFilter::execute(BitmapEx const& rBitmapEx) const
                 if (rPal[i].GetLuminance() >= mcSolarGreyThreshold)
                 {
                     BitmapColor aCol(rPal[i]);
-                    pWriteAcc->SetPaletteColor(i, aCol.Invert());
+                    aCol.Invert();
+                    pWriteAcc->SetPaletteColor(i, aCol);
                 }
             }
         }
@@ -50,7 +51,10 @@ BitmapEx BitmapSolarizeFilter::execute(BitmapEx const& rBitmapEx) const
                     aCol = pWriteAcc->GetPixelFromData(pScanline, nX);
 
                     if (aCol.GetLuminance() >= mcSolarGreyThreshold)
-                        pWriteAcc->SetPixelOnData(pScanline, nX, aCol.Invert());
+                    {
+                        aCol.Invert();
+                        pWriteAcc->SetPixelOnData(pScanline, nX, aCol);
+                    }
                 }
             }
         }
diff --git a/vcl/source/bitmap/BitmapTools.cxx b/vcl/source/bitmap/BitmapTools.cxx
index 380d46a7f7f7..531a49bc9cc5 100644
--- a/vcl/source/bitmap/BitmapTools.cxx
+++ b/vcl/source/bitmap/BitmapTools.cxx
@@ -675,7 +675,7 @@ static bool readAlpha( BitmapReadAccess const * pAlphaReadAcc, long nY, const lo
                 BitmapColor const& rColor(
                     pAlphaReadAcc->GetPaletteColor(*pReadScan));
                 pReadScan++;
-                nAlpha = data[ nOff ] = 255 - rColor.GetBlueOrIndex();
+                nAlpha = data[ nOff ] = 255 - rColor.GetIndex();
                 if( nAlpha != 255 )
                     bIsAlpha = true;
                 nOff += 4;
@@ -747,7 +747,7 @@ void CanvasCairoExtractBitmapData( BitmapEx const & aBmpEx, Bitmap & aBitmap, un
                 else
                     nAlpha = data[ nOff + 3 ] = 255;
 #endif
-                aColor = pBitmapReadAcc->GetPaletteColor(*pReadScan++).GetColor();
+                aColor = pBitmapReadAcc->GetPaletteColor(*pReadScan++);
 
 #ifdef OSL_BIGENDIAN
                 data[ nOff++ ] = premultiply_table[nAlpha][aColor.GetRed()];
@@ -888,7 +888,7 @@ void CanvasCairoExtractBitmapData( BitmapEx const & aBmpEx, Bitmap & aBitmap, un
 
             for( nX = 0; nX < nWidth; nX++ )
             {
-                aColor = pBitmapReadAcc->GetColor( nY, nX ).GetColor();
+                aColor = pBitmapReadAcc->GetColor( nY, nX );
 
                 // cairo need premultiplied color values
                 // TODO(rodo) handle endianness
@@ -1025,8 +1025,8 @@ void CanvasCairoExtractBitmapData( BitmapEx const & aBmpEx, Bitmap & aBitmap, un
 
                             // #i123564# background and foreground were exchanged; of course
                             // rPalette[0] is the background color
-                            o_rFront = rPalette[1].GetColor();
-                            o_rBack = rPalette[0].GetColor();
+                            o_rFront = rPalette[1];
+                            o_rBack = rPalette[0];
 
                             bRet = true;
                         }
diff --git a/vcl/source/bitmap/bitmappaint.cxx b/vcl/source/bitmap/bitmappaint.cxx
index 02df3c8a6b29..04b301d47d89 100644
--- a/vcl/source/bitmap/bitmappaint.cxx
+++ b/vcl/source/bitmap/bitmappaint.cxx
@@ -140,8 +140,9 @@ bool Bitmap::Invert()
                 Scanline pScanline = pAcc->GetScanline(nY);
                 for (long nX = 0; nX < nWidth; nX++)
                 {
-                    pAcc->SetPixelOnData(pScanline, nX,
-                                         pAcc->GetPixelFromData(pScanline, nX).Invert());
+                    BitmapColor aBmpColor = pAcc->GetPixelFromData(pScanline, nX);
+                    aBmpColor.Invert();
+                    pAcc->SetPixelOnData(pScanline, nX, aBmpColor);
                 }
             }
         }
@@ -830,9 +831,8 @@ bool Bitmap::Replace(const AlphaMask& rAlpha, const Color& rMergeColor)
             for (long nX = 0; nX < nWidth; nX++)
             {
                 aCol = pAcc->GetColor(nY, nX);
-                pNewAcc->SetPixelOnData(
-                    pScanline, nX,
-                    aCol.Merge(rMergeColor, 255 - pAlphaAcc->GetIndexFromData(pScanlineAlpha, nX)));
+                aCol.Merge(rMergeColor, 255 - pAlphaAcc->GetIndexFromData(pScanlineAlpha, nX));
+                pNewAcc->SetPixelOnData(pScanline, nX, aCol);
             }
         }
 
@@ -1132,11 +1132,10 @@ bool Bitmap::Blend(const AlphaMask& rAlpha, const Color& rBackgroundColor)
             Scanline pScanlineAlpha = pAlphaAcc->GetScanline(nY);
             for (long nX = 0; nX < nWidth; ++nX)
             {
-                pAcc->SetPixelOnData(
-                    pScanline, nX,
-                    pAcc->GetPixelFromData(pScanline, nX)
-                        .Merge(rBackgroundColor,
-                               255 - pAlphaAcc->GetIndexFromData(pScanlineAlpha, nX)));
+                BitmapColor aBmpColor = pAcc->GetPixelFromData(pScanline, nX);
+                aBmpColor.Merge(rBackgroundColor,
+                                255 - pAlphaAcc->GetIndexFromData(pScanlineAlpha, nX));
+                pAcc->SetPixelOnData(pScanline, nX, aBmpColor);
             }
         }
 
diff --git a/vcl/source/control/combobox.cxx b/vcl/source/control/combobox.cxx
index ddb644658a12..109c8374243b 100644
--- a/vcl/source/control/combobox.cxx
+++ b/vcl/source/control/combobox.cxx
@@ -1367,7 +1367,7 @@ const Wallpaper& ComboBox::GetDisplayBackground() const
     const Wallpaper& rBack = m_pImpl->m_pSubEdit->GetBackground();
     if( ! rBack.IsBitmap() &&
         ! rBack.IsGradient() &&
-        rBack.GetColor() == COL_TRANSPARENT
+        rBack == COL_TRANSPARENT
         )
         return Control::GetDisplayBackground();
     return rBack;
diff --git a/vcl/source/control/imp_listbox.cxx b/vcl/source/control/imp_listbox.cxx
index e2a78a1383f0..e7e2344f5096 100644
--- a/vcl/source/control/imp_listbox.cxx
+++ b/vcl/source/control/imp_listbox.cxx
@@ -1867,7 +1867,7 @@ void ImplListBoxWindow::DrawEntry(vcl::RenderContext& rRenderContext, sal_Int32
     if ( !maSeparators.empty() && ( isSeparator(nPos) || isSeparator(nPos-1) ) )
     {
         Color aOldLineColor(rRenderContext.GetLineColor());
-        rRenderContext.SetLineColor((GetBackground().GetColor() != COL_LIGHTGRAY) ? COL_LIGHTGRAY : COL_GRAY);
+        rRenderContext.SetLineColor((GetBackground() != COL_LIGHTGRAY) ? COL_LIGHTGRAY : COL_GRAY);
         Point aStartPos(0, nY);
         if (isSeparator(nPos))
             aStartPos.AdjustY(pEntry->getHeightWithMargin() - 1 );
diff --git a/vcl/source/filter/igif/gifread.cxx b/vcl/source/filter/igif/gifread.cxx
index 6378e63ab021..759e572fbbd3 100644
--- a/vcl/source/filter/igif/gifread.cxx
+++ b/vcl/source/filter/igif/gifread.cxx
@@ -232,7 +232,7 @@ void GIFReader::CreateBitmaps(long nWidth, long nHeight, BitmapPalette* pPal,
         aBmp8 = Bitmap(aSize, 8, pPal);
 
         if (!!aBmp8 && bWatchForBackgroundColor && aAnimation.Count())
-            aBmp8.Erase((*pPal)[nBackgroundColor].GetColor());
+            aBmp8.Erase((*pPal)[nBackgroundColor]);
         else
             aBmp8.Erase(COL_WHITE);
 
diff --git a/vcl/source/filter/png/pngread.cxx b/vcl/source/filter/png/pngread.cxx
index 58acc12c8d60..4107325bf7a9 100644
--- a/vcl/source/filter/png/pngread.cxx
+++ b/vcl/source/filter/png/pngread.cxx
@@ -843,8 +843,7 @@ void PNGReaderImpl::ImplGetBackground()
 
                 if (nCol < mxAcc->GetPaletteEntryCount())
                 {
-                    BitmapColor aBmpColor = mxAcc->GetPaletteColor(static_cast<sal_uInt8>(nCol));
-                    mxAcc->Erase(aBmpColor.GetColor());
+                    mxAcc->Erase(mxAcc->GetPaletteColor(static_cast<sal_uInt8>(nCol)));
                     break;
                 }
             }
@@ -858,9 +857,7 @@ void PNGReaderImpl::ImplGetBackground()
             {
                 // the color type 0 and 4 is always greyscale,
                 // so the return value can be used as index
-                sal_uInt8 nIndex = ImplScaleColor();
-                BitmapColor aBmpColor = mxAcc->GetPaletteColor(nIndex);
-                mxAcc->Erase(aBmpColor.GetColor());
+                mxAcc->Erase(mxAcc->GetPaletteColor(ImplScaleColor()));
             }
         }
         break;
diff --git a/vcl/source/gdi/bitmapex.cxx b/vcl/source/gdi/bitmapex.cxx
index e5aea9401e9f..2ea870e341e6 100644
--- a/vcl/source/gdi/bitmapex.cxx
+++ b/vcl/source/gdi/bitmapex.cxx
@@ -324,7 +324,7 @@ bool BitmapEx::Invert()
         bRet = maBitmap.Invert();
 
         if (bRet && (meTransparent == TransparentType::Color))
-            maTransparentColor = BitmapColor(maTransparentColor).Invert().GetColor();
+            maTransparentColor.Invert();
     }
 
     return bRet;
@@ -705,10 +705,9 @@ sal_uInt8 BitmapEx::GetTransparency(sal_Int32 nX, sal_Int32 nY) const
                     if(pRead)
                     {
                         const BitmapColor aBmpColor = pRead->GetColor(nY, nX);
-                        const Color aColor = aBmpColor.GetColor();
 
                         // If color is not equal to TransparentColor, we are not transparent
-                        if (aColor != maTransparentColor)
+                        if (aBmpColor != maTransparentColor)
                             nTransparency = 0x00;
 
                     }
@@ -753,7 +752,7 @@ Color BitmapEx::GetPixelColor(sal_Int32 nX, sal_Int32 nY) const
     Bitmap::ScopedReadAccess pReadAccess( const_cast<Bitmap&>(maBitmap) );
     assert(pReadAccess);
 
-    Color aColor = pReadAccess->GetColor(nY, nX).GetColor();
+    BitmapColor aColor = pReadAccess->GetColor(nY, nX);
 
     if (IsAlpha())
     {
@@ -1310,7 +1309,7 @@ void BitmapEx::setAlphaFrom( sal_uInt8 cIndexFrom, sal_Int8 nAlphaTo )
             Scanline pScanlineRead = pReadAccess->GetScanline( nY );
             for ( long nX = 0; nX < pReadAccess->Width(); nX++ )
             {
-                const sal_uInt8 cIndex = pReadAccess->GetPixelFromData( pScanlineRead, nX ).GetBlueOrIndex();
+                const sal_uInt8 cIndex = pReadAccess->GetPixelFromData( pScanlineRead, nX ).GetIndex();
                 if ( cIndex == cIndexFrom )
                     pWriteAccess->SetPixelOnData( pScanline, nX, BitmapColor(nAlphaTo) );
             }
diff --git a/vcl/source/gdi/bmpacc2.cxx b/vcl/source/gdi/bmpacc2.cxx
index 4ac7b84c3e7c..0c382d08db91 100644
--- a/vcl/source/gdi/bmpacc2.cxx
+++ b/vcl/source/gdi/bmpacc2.cxx
@@ -99,7 +99,7 @@ BitmapColor BitmapReadAccess::GetPixelForN8BitPal(ConstScanline pScanline, long
 
 void BitmapReadAccess::SetPixelForN8BitPal(Scanline pScanline, long nX, const BitmapColor& rBitmapColor, const ColorMask&)
 {
-    pScanline[ nX ] = rBitmapColor.GetBlueOrIndex();
+    pScanline[ nX ] = rBitmapColor.GetIndex();
 }
 
 BitmapColor BitmapReadAccess::GetPixelForN8BitTcMask(ConstScanline pScanline, long nX, const ColorMask& rMask)
diff --git a/vcl/source/gdi/print2.cxx b/vcl/source/gdi/print2.cxx
index 3ec7bbf494db..1ca7014778f5 100644
--- a/vcl/source/gdi/print2.cxx
+++ b/vcl/source/gdi/print2.cxx
@@ -221,7 +221,7 @@ void ImplConvertTransparentAction( GDIMetaFile&        o_rMtf,
             Color aActualColor(aBgColor);
 
             if (pRA->HasPalette())
-                aActualColor = pRA->GetBestPaletteColor(aBgColor).GetColor();
+                aActualColor = pRA->GetBestPaletteColor(aBgColor);
 
             pRA.reset();
 
diff --git a/vcl/source/graphic/UnoGraphicTransformer.cxx b/vcl/source/graphic/UnoGraphicTransformer.cxx
index f50101fff6f4..13e1adbee114 100644
--- a/vcl/source/graphic/UnoGraphicTransformer.cxx
+++ b/vcl/source/graphic/UnoGraphicTransformer.cxx
@@ -56,10 +56,10 @@ uno::Reference< graphic::XGraphic > SAL_CALL GraphicTransformer::colorChange(
     BitmapColor aBmpColorFrom(static_cast< sal_uInt8 >(nColorFrom), static_cast< sal_uInt8 >(nColorFrom >> 8), static_cast< sal_uInt8 >(nColorFrom >> 16));
     BitmapColor aBmpColorTo( static_cast< sal_uInt8 >(nColorTo), static_cast< sal_uInt8 >(nColorTo >> 8), static_cast< sal_uInt8 >(nColorTo  >> 16));
 
-    Color aColorFrom(aBmpColorFrom.GetColor());
-    Color aColorTo(aBmpColorTo.GetColor());
+    Color aColorFrom(aBmpColorFrom);
+    Color aColorTo(aBmpColorTo);
 
-    const sal_uInt8 cIndexFrom = aBmpColorFrom.GetBlueOrIndex();
+    const sal_uInt8 cIndexFrom = aBmpColorFrom.GetIndex();
 
     if (aGraphic.GetType() == GraphicType::Bitmap ||
         aGraphic.GetType() == GraphicType::GdiMetafile)
diff --git a/vcl/source/outdev/bitmap.cxx b/vcl/source/outdev/bitmap.cxx
index 0e57b2a9f203..5322a0a29cea 100644
--- a/vcl/source/outdev/bitmap.cxx
+++ b/vcl/source/outdev/bitmap.cxx
@@ -1580,8 +1580,8 @@ Bitmap OutputDevice::BlendBitmap(
                                     nMapX = aBmpRect.Right() - nMapX;
                                 }
                                 aDstCol = pB->GetPixelFromData( pBScan, nX );
-                                pB->SetPixelOnData( pBScan, nX, aDstCol.Merge( pP->GetPaletteColor( pPScan[ nMapX ] ),
-                                                                                pAScan[ nMapX ] ) );
+                                aDstCol.Merge( pP->GetPaletteColor( pPScan[ nMapX ] ), pAScan[ nMapX ] );
+                                pB->SetPixelOnData( pBScan, nX, aDstCol );
                             }
                         }
                     }
@@ -1609,8 +1609,8 @@ Bitmap OutputDevice::BlendBitmap(
                                 nMapX = aBmpRect.Right() - nMapX;
                             }
                             aDstCol = pB->GetPixelFromData( pBScan, nX );
-                            pB->SetPixelOnData( pBScan, nX, aDstCol.Merge( pP->GetColor( nMapY, nMapX ),
-                                                                 pAScan[ nMapX ] ) );
+                            aDstCol.Merge( pP->GetColor( nMapY, nMapX ), pAScan[ nMapX ] );
+                            pB->SetPixelOnData( pBScan, nX, aDstCol );
                         }
                     }
                 }
diff --git a/vcl/source/outdev/transparent.cxx b/vcl/source/outdev/transparent.cxx
index 205de6baaec1..a2fbbf6c6ac2 100644
--- a/vcl/source/outdev/transparent.cxx
+++ b/vcl/source/outdev/transparent.cxx
@@ -523,7 +523,8 @@ void OutputDevice::EmulateDrawTransparent ( const tools::PolyPolygon& rPolyPoly,
                             for( sal_uInt16 i = 0; i < nCount; i++ )
                             {
                                 BitmapColor aCol( rPal[ i ] );
-                                pMap[ i ] = BitmapColor( static_cast<sal_uInt8>(rPal.GetBestIndex( aCol.Merge( aFillCol, cTrans ) )) );
+                                aCol.Merge( aFillCol, cTrans );
+                                pMap[ i ] = BitmapColor( static_cast<sal_uInt8>(rPal.GetBestIndex( aCol )) );
                             }
 
                             if( pR->GetScanlineFormat() == ScanlineFormat::N1BitMsbPal &&
@@ -608,7 +609,8 @@ void OutputDevice::EmulateDrawTransparent ( const tools::PolyPolygon& rPolyPoly,
                                         if( pR->GetPixelFromData( pScanlineRead, nX ) == aBlack )
                                         {
                                             aPixCol = pW->GetColor( nY, nX );
-                                            pW->SetPixelOnData(pScanline, nX, aPixCol.Merge( aFillCol, cTrans ) );
+                                            aPixCol.Merge(aFillCol, cTrans);
+                                            pW->SetPixelOnData(pScanline, nX, aPixCol);
                                         }
                                     }
                                 }