make conversions between BitmapColor and sal_uInt8 explicit

Implicit conversions are a dangerous cause of confusion as seen
in http://markmail.org/thread/a4copx2di7cxeowg and require tricky
rewrites to work around them, this change cleans them up and
disables them.

(cherry picked from commit 2d9d5c8d6beb7fb0a7dafa0c1c4d10a25d7200fd)

Conflicts:
filter/source/graphicfilter/egif/egif.cxx
filter/source/graphicfilter/epbm/epbm.cxx
filter/source/graphicfilter/epgm/epgm.cxx
filter/source/graphicfilter/ipbm/ipbm.cxx
filter/source/graphicfilter/ipsd/ipsd.cxx
sd/source/ui/slidesorter/view/SlsButtonBar.cxx
svtools/source/filter/igif/gifread.cxx
svtools/source/filter/jpeg/jpeg.cxx
svtools/source/filter/wmf/winwmf.cxx
svtools/source/graphic/grfmgr2.cxx
vcl/inc/vcl/bmpacc.hxx
vcl/inc/vcl/salbtype.hxx
vcl/source/gdi/bitmap.cxx
vcl/source/gdi/bitmap3.cxx
vcl/source/gdi/outdev2.cxx

Change-Id: I1d163c66782c2750aeee00725dbb2b614507c0d4
(cherry picked from commit ff80c37b18b941712fb967a0c1d48813b47c0583)

2 files changed, 15 insertions, 17 deletions

diff --git a/svtools/source/graphic/grfmgr2.cxx b/svtools/source/graphic/grfmgr2.cxx
index 7eb8233fb9fa..45c368612b2c 100644
--- a/svtools/source/graphic/grfmgr2.cxx
+++ b/svtools/source/graphic/grfmgr2.cxx
@@ -423,14 +423,14 @@ sal_Bool ImplCreateRotatedScaled( const BitmapEx& rBmpEx, const GraphicAttr& rAt
                                 nTmpX = pMapIX[ nUnRotX ]; nTmpFX = pMapFX[ nUnRotX ];
                                 nTmpY = pMapIY[ nUnRotY ], nTmpFY = pMapFY[ nUnRotY ];
 
-                                const BitmapColor& rCol0 = pReadAccess->GetPaletteColor( pReadAccess->GetPixel( nTmpY, nTmpX ) );
-                                const BitmapColor& rCol1 = pReadAccess->GetPaletteColor( pReadAccess->GetPixel( nTmpY, ++nTmpX ) );
+                                const BitmapColor& rCol0 = pReadAccess->GetPaletteColor( pReadAccess->GetPixelIndex( nTmpY, nTmpX ) );
+                                const BitmapColor& rCol1 = pReadAccess->GetPaletteColor( pReadAccess->GetPixelIndex( nTmpY, ++nTmpX ) );
                                 cR0 = MAP( rCol0.GetRed(), rCol1.GetRed(), nTmpFX );
                                 cG0 = MAP( rCol0.GetGreen(), rCol1.GetGreen(), nTmpFX );
                                 cB0 = MAP( rCol0.GetBlue(), rCol1.GetBlue(), nTmpFX );
 
-                                const BitmapColor& rCol3 = pReadAccess->GetPaletteColor( pReadAccess->GetPixel( ++nTmpY, nTmpX ) );
-                                const BitmapColor& rCol2 = pReadAccess->GetPaletteColor( pReadAccess->GetPixel( nTmpY, --nTmpX ) );
+                                const BitmapColor& rCol3 = pReadAccess->GetPaletteColor( pReadAccess->GetPixelIndex( ++nTmpY, nTmpX ) );
+                                const BitmapColor& rCol2 = pReadAccess->GetPaletteColor( pReadAccess->GetPixelIndex( nTmpY, --nTmpX ) );
                                 cR1 = MAP( rCol2.GetRed(), rCol3.GetRed(), nTmpFX );
                                 cG1 = MAP( rCol2.GetGreen(), rCol3.GetGreen(), nTmpFX );
                                 cB1 = MAP( rCol2.GetBlue(), rCol3.GetBlue(), nTmpFX );
@@ -527,10 +527,10 @@ sal_Bool ImplCreateRotatedScaled( const BitmapEx& rBmpEx, const GraphicAttr& rAt
                             {
                                 for (int xIn = xStart; xIn <= xEnd; xIn++)
                                 {
-                                    aColor = pReadAccess->GetPixel( yIn, xIn );
-
                                     if( pReadAccess->HasPalette() )
-                                        aColor = pReadAccess->GetPaletteColor( aColor );
+                                        aColor = pReadAccess->GetPaletteColor( pReadAccess->GetPixelIndex( yIn, xIn ) );
+                                    else
+                                        aColor = pReadAccess->GetPixel( yIn, xIn );
 
                                     aSumRed   += aColor.GetRed();
                                     aSumGreen += aColor.GetGreen();
diff --git a/svtools/source/graphic/transformer.cxx b/svtools/source/graphic/transformer.cxx
index 874bb346e59d..1b8e3c2eef1e 100644
--- a/svtools/source/graphic/transformer.cxx
+++ b/svtools/source/graphic/transformer.cxx
@@ -54,22 +54,19 @@ GraphicTransformer::~GraphicTransformer()
 
 // ------------------------------------------------------------------------------
 
-void setAlpha( Bitmap& rBitmap, AlphaMask& rAlpha, sal_Int32 nColorFrom, sal_Int8 nAlphaTo )
+void setAlpha( Bitmap& rBitmap, AlphaMask& rAlpha, sal_uInt8 cIndexFrom, sal_Int8 nAlphaTo )
 {
     BitmapWriteAccess* pWriteAccess = rAlpha.AcquireWriteAccess();
     BitmapReadAccess* pReadAccess = rBitmap.AcquireReadAccess();
-    BitmapColor aColorFrom( static_cast< sal_uInt8 >( nColorFrom >> 16 ),
-        static_cast< sal_uInt8 >( nColorFrom >> 8 ),
-        static_cast< sal_uInt8 >( nColorFrom ) );
     if ( pReadAccess && pWriteAccess )
     {
         for ( sal_Int32 nY = 0; nY < pReadAccess->Height(); nY++ )
         {
             for ( sal_Int32 nX = 0; nX < pReadAccess->Width(); nX++ )
             {
-                BitmapColor aColor( pReadAccess->GetPixel( nY, nX ) );
-                if ( aColor == aColorFrom )
-                    pWriteAccess->SetPixel( nY, nX, nAlphaTo );
+                const sal_uInt8 cIndex = pReadAccess->GetPixelIndex( nY, nX );
+                if ( cIndex == cIndexFrom )
+                    pWriteAccess->SetPixelIndex( nY, nX, nAlphaTo );
             }
         }
     }
@@ -87,6 +84,7 @@ uno::Reference< graphic::XGraphic > SAL_CALL GraphicTransformer::colorChange(
 
     BitmapColor aColorFrom( static_cast< sal_uInt8 >( nColorFrom ), static_cast< sal_uInt8 >( nColorFrom >> 8 ), static_cast< sal_uInt8 >( nColorFrom >> 16 ) );
     BitmapColor aColorTo( static_cast< sal_uInt8 >( nColorTo ), static_cast< sal_uInt8 >( nColorTo >> 8 ), static_cast< sal_uInt8 >( nColorTo  >> 16 ) );
+    const sal_uInt8 cIndexFrom = aColorFrom.GetBlueOrIndex();
 
     if ( aGraphic.GetType() == GRAPHIC_BITMAP )
     {
@@ -96,7 +94,7 @@ uno::Reference< graphic::XGraphic > SAL_CALL GraphicTransformer::colorChange(
         if ( aBitmapEx.IsAlpha() )
         {
             AlphaMask aAlphaMask( aBitmapEx.GetAlpha() );
-            setAlpha( aBitmap, aAlphaMask, aColorFrom, nAlphaTo );
+            setAlpha( aBitmap, aAlphaMask, cIndexFrom, nAlphaTo );
             aBitmap.Replace( aColorFrom, aColorTo, nTolerance );
             aGraphic = ::Graphic( BitmapEx( aBitmap, aAlphaMask ) );
         }
@@ -113,7 +111,7 @@ uno::Reference< graphic::XGraphic > SAL_CALL GraphicTransformer::colorChange(
             else
             {
                 AlphaMask aAlphaMask( aBitmapEx.GetMask() );
-                setAlpha( aBitmap, aAlphaMask, aColorFrom, nAlphaTo );
+                setAlpha( aBitmap, aAlphaMask, cIndexFrom, nAlphaTo );
                 aBitmap.Replace( aColorFrom, aColorTo, nTolerance );
                 aGraphic = ::Graphic( BitmapEx( aBitmap, aAlphaMask ) );
             }
@@ -129,7 +127,7 @@ uno::Reference< graphic::XGraphic > SAL_CALL GraphicTransformer::colorChange(
             else
             {
                 AlphaMask aAlphaMask( aBitmapEx.GetSizePixel() );
-                setAlpha( aBitmap, aAlphaMask, aColorFrom, nAlphaTo );
+                setAlpha( aBitmap, aAlphaMask, cIndexFrom, nAlphaTo );
                 aBitmap.Replace( aColorFrom, aColorTo, nTolerance );
                 aGraphic = ::Graphic( BitmapEx( aBitmap, aAlphaMask ) );
             }