diff options
Diffstat (limited to 'vcl/source/gdi/outdev2.cxx')
| -rw-r--r-- | vcl/source/gdi/outdev2.cxx | 71 |
1 files changed, 28 insertions, 43 deletions
diff --git a/vcl/source/gdi/outdev2.cxx b/vcl/source/gdi/outdev2.cxx index 3826a3dbc7b0..bea307a4c38d 100644 --- a/vcl/source/gdi/outdev2.cxx +++ b/vcl/source/gdi/outdev2.cxx @@ -1614,6 +1614,18 @@ void OutputDevice::DrawPixel( const Polygon& rPts, const Color& rColor ) // ------------------------------------------------------------------------ +namespace +{ + BYTE lcl_calcColor( const BYTE nSourceColor, const BYTE nSourceOpaq, const BYTE nDestColor ) + { + int c = ( (int)nDestColor * ( 255 - nSourceOpaq ) ) + + (int)nSourceOpaq * (int)nSourceColor; + return BYTE( c / 255 ); + } +} + +// ------------------------------------------------------------------------ + Bitmap OutputDevice::ImplBlendWithAlpha( Bitmap aBmp, BitmapReadAccess* pP, BitmapReadAccess* pA, @@ -1626,7 +1638,6 @@ Bitmap OutputDevice::ImplBlendWithAlpha( Bitmap aBmp, const long* pMapY ) { BitmapColor aDstCol,aSrcCol; - BYTE nSrcAlpha, nDstAlpha; Bitmap res; int nX, nOutX, nY, nOutY; @@ -1660,36 +1671,23 @@ Bitmap OutputDevice::ImplBlendWithAlpha( Bitmap aBmp, aSrcCol = pP->GetColor( nMapY, nMapX ); aDstCol = pB->GetColor( nY, nX ); - nSrcAlpha = 255 - pA->GetPixel( nMapY, nMapX ).GetBlueOrIndex(); - nDstAlpha = 255 - pAlphaW->GetPixel( nY, nX ).GetBlueOrIndex(); + const BYTE nSrcOpaq = 255 - pA->GetPixel( nMapY, nMapX ).GetBlueOrIndex(); + const BYTE nDstOpaq = 255 - pAlphaW->GetPixel( nY, nX ).GetBlueOrIndex(); - if( nSrcAlpha + nDstAlpha == 0 ) - { - // #i70653# zero alpha -> zero color values - aIndex.SetIndex( (BYTE) ( nVCLRLut[ ( nVCLLut[ 0 ] + nD ) >> 16UL ] + - nVCLGLut[ ( nVCLLut[ 0 ] + nD ) >> 16UL ] + - nVCLBLut[ ( nVCLLut[ 0 ] + nD ) >> 16UL ] ) ); - } - else - { - aDstCol.SetRed( (BYTE)(((int)(aSrcCol.GetRed())*nSrcAlpha + (int)(aDstCol.GetRed())*nDstAlpha) / - (nSrcAlpha+nDstAlpha)) ); - aDstCol.SetGreen( (BYTE)(((int)(aSrcCol.GetGreen())*nSrcAlpha + (int)(aDstCol.GetGreen())*nDstAlpha) / - (nSrcAlpha+nDstAlpha)) ); - aDstCol.SetBlue( (BYTE)(((int)(aSrcCol.GetBlue())*nSrcAlpha + (int)(aDstCol.GetBlue())*nDstAlpha) / - (nSrcAlpha+nDstAlpha)) ); - - aIndex.SetIndex( (BYTE) ( nVCLRLut[ ( nVCLLut[ aDstCol.GetRed() ] + nD ) >> 16UL ] + - nVCLGLut[ ( nVCLLut[ aDstCol.GetGreen() ] + nD ) >> 16UL ] + - nVCLBLut[ ( nVCLLut[ aDstCol.GetBlue() ] + nD ) >> 16UL ] ) ); - } + aDstCol.SetRed( lcl_calcColor( aSrcCol.GetRed(), nSrcOpaq, aDstCol.GetRed() ) ); + aDstCol.SetBlue( lcl_calcColor( aSrcCol.GetBlue(), nSrcOpaq, aDstCol.GetBlue() ) ); + aDstCol.SetGreen( lcl_calcColor( aSrcCol.GetGreen(), nSrcOpaq, aDstCol.GetGreen() ) ); + + aIndex.SetIndex( (BYTE) ( nVCLRLut[ ( nVCLLut[ aDstCol.GetRed() ] + nD ) >> 16UL ] + + nVCLGLut[ ( nVCLLut[ aDstCol.GetGreen() ] + nD ) >> 16UL ] + + nVCLBLut[ ( nVCLLut[ aDstCol.GetBlue() ] + nD ) >> 16UL ] ) ); pW->SetPixel( nY, nX, aIndex ); // Have to perform the compositing 'algebra' in // the inverse alpha space (with 255 meaning // opaque), otherwise, transitivity is not // achieved. - nSrcAlpha = 255-COLOR_CHANNEL_MERGE( 255, (BYTE)nDstAlpha, nSrcAlpha ); + const BYTE nSrcAlpha = 255-COLOR_CHANNEL_MERGE( 255, (BYTE)nDstOpaq, nSrcOpaq ); aIndex.SetIndex( (BYTE) ( nVCLRLut[ ( nVCLLut[ nSrcAlpha ] + nD ) >> 16UL ] + nVCLGLut[ ( nVCLLut[ nSrcAlpha ] + nD ) >> 16UL ] + @@ -1718,25 +1716,12 @@ Bitmap OutputDevice::ImplBlendWithAlpha( Bitmap aBmp, aSrcCol = pP->GetColor( nMapY, nMapX ); aDstCol = pB->GetColor( nY, nX ); - nSrcAlpha = 255 - pA->GetPixel( nMapY, nMapX ).GetBlueOrIndex(); - nDstAlpha = 255 - pAlphaW->GetPixel( nY, nX ).GetBlueOrIndex(); + const BYTE nSrcOpaq = 255 - pA->GetPixel( nMapY, nMapX ).GetBlueOrIndex(); + const BYTE nDstOpaq = 255 - pAlphaW->GetPixel( nY, nX ).GetBlueOrIndex(); - if( nSrcAlpha + nDstAlpha == 0 ) - { - // #i70653# zero alpha -> zero color values - aDstCol.SetRed(0); - aDstCol.SetGreen(0); - aDstCol.SetBlue(0); - } - else - { - aDstCol.SetRed( (BYTE)(((int)(aSrcCol.GetRed())*nSrcAlpha + (int)(aDstCol.GetRed())*nDstAlpha) / - (nSrcAlpha+nDstAlpha)) ); - aDstCol.SetGreen( (BYTE)(((int)(aSrcCol.GetGreen())*nSrcAlpha + (int)(aDstCol.GetGreen())*nDstAlpha) / - (nSrcAlpha+nDstAlpha)) ); - aDstCol.SetBlue( (BYTE)(((int)(aSrcCol.GetBlue())*nSrcAlpha + (int)(aDstCol.GetBlue())*nDstAlpha) / - (nSrcAlpha+nDstAlpha)) ); - } + aDstCol.SetRed( lcl_calcColor( aSrcCol.GetRed(), nSrcOpaq, aDstCol.GetRed() ) ); + aDstCol.SetBlue( lcl_calcColor( aSrcCol.GetBlue(), nSrcOpaq, aDstCol.GetBlue() ) ); + aDstCol.SetGreen( lcl_calcColor( aSrcCol.GetGreen(), nSrcOpaq, aDstCol.GetGreen() ) ); pB->SetPixel( nY, nX, aDstCol ); @@ -1744,7 +1729,7 @@ Bitmap OutputDevice::ImplBlendWithAlpha( Bitmap aBmp, // the inverse alpha space (with 255 meaning // opaque), otherwise, transitivity is not // achieved. - nSrcAlpha = 255-COLOR_CHANNEL_MERGE( 255, (BYTE)nDstAlpha, nSrcAlpha ); + const BYTE nSrcAlpha = 255-COLOR_CHANNEL_MERGE( 255, (BYTE)nDstOpaq, nSrcOpaq ); pAlphaW->SetPixel( nY, nX, Color(nSrcAlpha, nSrcAlpha, nSrcAlpha) ); } |