ofz: speed up bitmap image fuzzing

Change-Id: I73c9ee7aef7062e3cb025c6ae0f3bb6a91485330
Reviewed-on: https://gerrit.libreoffice.org/48983
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

4 files changed, 88 insertions, 69 deletions

diff --git a/filter/source/graphicfilter/icgm/bitmap.cxx b/filter/source/graphicfilter/icgm/bitmap.cxx
index eb2f337d8e4b..bcc08874b292 100644
--- a/filter/source/graphicfilter/icgm/bitmap.cxx
+++ b/filter/source/graphicfilter/icgm/bitmap.cxx
@@ -94,9 +94,10 @@ void CGMBitmap::ImplGetBitmap( CGMBitmapDescriptor& rDesc )
                     for ( ny = 0; --nyCount ; ny++, rDesc.mpBuf += rDesc.mnScanSize )
                     {
                         nxC = nxCount;
+                        Scanline pScanline = rDesc.mpAcc->GetScanline(ny);
                         for ( nx = 0; --nxC; nx++ )
                         {   // this is not fast, but a one bit/pixel format is rarely used
-                            rDesc.mpAcc->SetPixelIndex( ny, nx, static_cast<sal_uInt8>( (*( rDesc.mpBuf + (nx >> 3)) >> ((nx & 7)^7))) & 1 );
+                            rDesc.mpAcc->SetPixelOnData(pScanline, nx, BitmapColor(static_cast<sal_uInt8>( (*( rDesc.mpBuf + (nx >> 3)) >> ((nx & 7)^7))) & 1));
                         }
                     }
                 }
@@ -108,9 +109,10 @@ void CGMBitmap::ImplGetBitmap( CGMBitmapDescriptor& rDesc )
                     for ( ny = 0; --nyCount; ny++, rDesc.mpBuf += rDesc.mnScanSize )
                     {
                         nxC = nxCount;
+                        Scanline pScanline = rDesc.mpAcc->GetScanline(ny);
                         for ( nx = 0; --nxC; nx++ )
                         {   // this is not fast, but a two bits/pixel format is rarely used
-                            rDesc.mpAcc->SetPixelIndex( ny, nx, static_cast<sal_uInt8>( (*(rDesc.mpBuf + (nx >> 2)) >> (((nx & 3)^3) << 1))) & 3 );
+                            rDesc.mpAcc->SetPixelOnData(pScanline, nx, BitmapColor(static_cast<sal_uInt8>( (*(rDesc.mpBuf + (nx >> 2)) >> (((nx & 3)^3) << 1))) & 3));
                         }
                     }
                 }
@@ -127,11 +129,12 @@ void CGMBitmap::ImplGetBitmap( CGMBitmapDescriptor& rDesc )
                         for ( nx = 0; --nxC; nx++ )
                         {
                             nDat = *pTemp++;
-                            rDesc.mpAcc->SetPixelIndex( ny, nx, static_cast<sal_uInt8>(nDat >> 4) );
+                            Scanline pScanline = rDesc.mpAcc->GetScanline(ny);
+                            rDesc.mpAcc->SetPixelOnData(pScanline, nx, BitmapColor(static_cast<sal_uInt8>(nDat >> 4)));
                             if ( --nxC )
                             {
-                                nx ++;
-                                rDesc.mpAcc->SetPixelIndex( ny, nx, static_cast<sal_uInt8>(nDat & 15) );
+                                ++nx;
+                                rDesc.mpAcc->SetPixelOnData(pScanline, nx, BitmapColor(static_cast<sal_uInt8>(nDat & 15)));
                             }
                             else
                                 break;
@@ -146,10 +149,11 @@ void CGMBitmap::ImplGetBitmap( CGMBitmapDescriptor& rDesc )
                     for ( ny = 0; --nyCount; ny++, rDesc.mpBuf += rDesc.mnScanSize )
                     {
                         sal_uInt8* pTemp = rDesc.mpBuf;
+                        Scanline pScanline = rDesc.mpAcc->GetScanline(ny);
                         nxC = nxCount;
                         for ( nx = 0; --nxC; nx++ )
                         {
-                            rDesc.mpAcc->SetPixelIndex( ny, nx, *(pTemp++) );
+                            rDesc.mpAcc->SetPixelOnData(pScanline, nx, BitmapColor(*(pTemp++)));
                         }
                     }
                 }
@@ -162,12 +166,13 @@ void CGMBitmap::ImplGetBitmap( CGMBitmapDescriptor& rDesc )
                     {
                         sal_uInt8* pTemp = rDesc.mpBuf;
                         nxC = nxCount;
+                        Scanline pScanline = rDesc.mpAcc->GetScanline(ny);
                         for ( nx = 0; --nxC; nx++ )
                         {
                             aBitmapColor.SetRed( *pTemp++ );
                             aBitmapColor.SetGreen( *pTemp++ );
                             aBitmapColor.SetBlue( *pTemp++ );
-                            rDesc.mpAcc->SetPixel( ny, nx, aBitmapColor );
+                            rDesc.mpAcc->SetPixelOnData(pScanline, nx, aBitmapColor);
                         }
                     }
                 }
diff --git a/filter/source/graphicfilter/ipict/ipict.cxx b/filter/source/graphicfilter/ipict/ipict.cxx
index 323501eaffeb..8239fe05bed2 100644
--- a/filter/source/graphicfilter/ipict/ipict.cxx
+++ b/filter/source/graphicfilter/ipict/ipict.cxx
@@ -238,8 +238,9 @@ private:
     void SetLineColor( const Color& rColor );
     void SetFillColor( const Color& rColor );
 
-  // OSNOLA: returns the text encoding which must be used for system id
-  static rtl_TextEncoding GetTextEncoding (sal_uInt16 fId = 0xFFFF);
+    // OSNOLA: returns the text encoding which must be used for system id
+    static rtl_TextEncoding GetTextEncoding (sal_uInt16 fId = 0xFFFF);
+
 public:
 
     PictReader()
@@ -258,46 +259,46 @@ public:
 
 };
 
-
-#define SETBYTE                                         \
-    switch ( nPixelSize )                               \
-    {                                                   \
-        case 1 :                                        \
-            pAcc->SetPixelIndex( ny, nx++, nDat >> 7 ); \
-            if ( nx == nWidth ) break;                  \
-            pAcc->SetPixelIndex( ny, nx++, nDat >> 6 ); \
-            if ( nx == nWidth ) break;                  \
-            pAcc->SetPixelIndex( ny, nx++, nDat >> 5 ); \
-            if ( nx == nWidth ) break;                  \
-            pAcc->SetPixelIndex( ny, nx++, nDat >> 4 ); \
-            if ( nx == nWidth ) break;                  \
-            pAcc->SetPixelIndex( ny, nx++, nDat >> 3 ); \
-            if ( nx == nWidth ) break;                  \
-            pAcc->SetPixelIndex( ny, nx++, nDat >> 2 ); \
-            if ( nx == nWidth ) break;                  \
-            pAcc->SetPixelIndex( ny, nx++, nDat >> 1 ); \
-            if ( nx == nWidth ) break;                  \
-            pAcc->SetPixelIndex( ny, nx++, nDat );      \
-            break;                                      \
-        case 2 :                                        \
-            pAcc->SetPixelIndex( ny, nx++, nDat >> 6 ); \
-            if ( nx == nWidth ) break;                  \
-            pAcc->SetPixelIndex( ny, nx++, (nDat>>4)&3);\
-            if ( nx == nWidth ) break;                  \
-            pAcc->SetPixelIndex( ny, nx++, (nDat>>2)&3 );\
-            if ( nx == nWidth ) break;                  \
-            pAcc->SetPixelIndex( ny, nx++, nDat & 3);       \
-            break;                                      \
-        case 4 :                                        \
-            pAcc->SetPixelIndex( ny, nx++, nDat >> 4 ); \
-            if ( nx == nWidth ) break;                  \
-            pAcc->SetPixelIndex( ny, nx++, nDat );      \
-            break;                                      \
-        case 8 :                                        \
-            pAcc->SetPixelIndex( ny, nx++, nDat );      \
-            break;                                      \
+static void SetByte(sal_uInt16& nx, Scanline pScanline, BitmapWriteAccess* pAcc, sal_uInt16 nPixelSize, sal_uInt8 nDat, sal_uInt16 nWidth)
+{
+    switch (nPixelSize)
+    {
+        case 1:
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat >> 7));
+            if ( nx == nWidth ) break;
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat >> 6));
+            if ( nx == nWidth ) break;
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat >> 5));
+            if ( nx == nWidth ) break;
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat >> 4));
+            if ( nx == nWidth ) break;
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat >> 3));
+            if ( nx == nWidth ) break;
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat >> 2));
+            if ( nx == nWidth ) break;
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat >> 1));
+            if ( nx == nWidth ) break;
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat));
+            break;
+        case 2:
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat >> 6));
+            if ( nx == nWidth ) break;
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor((nDat>>4)&3));
+            if ( nx == nWidth ) break;
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor((nDat>>2)&3));
+            if ( nx == nWidth ) break;
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat & 3));
+            break;
+        case 4:
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat >> 4));
+            if ( nx == nWidth ) break;
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat));
+            break;
+        case 8:
+            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nDat));
+            break;
     }
-
+}
 
 #define BITMAPERROR                                     \
 {                                                       \
@@ -876,6 +877,7 @@ sal_uLong PictReader::ReadPixMapEtc( Bitmap &rBitmap, bool bBaseAddr, bool bColo
 
         for (sal_uInt16 ny = 0; ny < nHeight; ++ny)
         {
+            Scanline pScanline = pAcc->GetScanline(ny);
             sal_uInt16 nx = 0;
             if ( nRowBytes < 8 || nPackType == 1 )
             {
@@ -883,7 +885,7 @@ sal_uLong PictReader::ReadPixMapEtc( Bitmap &rBitmap, bool bBaseAddr, bool bColo
                 {
                     pPict->ReadUChar( nDat );
                     if ( nx < nWidth )
-                        SETBYTE;
+                        SetByte(nx, pScanline, pAcc, nPixelSize, nDat, nWidth);
                 }
                 nDataSize += nRowBytes;
             }
@@ -914,7 +916,7 @@ sal_uLong PictReader::ReadPixMapEtc( Bitmap &rBitmap, bool bBaseAddr, bool bColo
                         {
                             pPict->ReadUChar( nDat );
                             if ( nx < nWidth )
-                                SETBYTE;
+                                SetByte(nx, pScanline, pAcc, nPixelSize, nDat, nWidth);
                         }
                         nByteCount -= 1 + nCount;
                     }
@@ -925,7 +927,7 @@ sal_uLong PictReader::ReadPixMapEtc( Bitmap &rBitmap, bool bBaseAddr, bool bColo
                         for (size_t i = 0; i < nCount; ++i)
                         {
                             if ( nx < nWidth )
-                                SETBYTE;
+                                SetByte(nx, pScanline, pAcc, nPixelSize, nDat, nWidth);
                         }
                         nByteCount -= 2;
                     }
@@ -962,13 +964,14 @@ sal_uLong PictReader::ReadPixMapEtc( Bitmap &rBitmap, bool bBaseAddr, bool bColo
             sal_uInt16 nx = 0;
             if ( nRowBytes < 8 || nPackType == 1 )
             {
+                Scanline pScanline = pAcc->GetScanline(ny);
                 for (size_t i = 0; i < nWidth; ++i)
                 {
                     pPict->ReadUInt16( nD );
                     nRed = static_cast<sal_uInt8>( nD >> 7 );
                     nGreen = static_cast<sal_uInt8>( nD >> 2 );
                     nBlue = static_cast<sal_uInt8>( nD << 3 );
-                    pAcc->SetPixel( ny, nx++, BitmapColor( nRed, nGreen, nBlue ) );
+                    pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nRed, nGreen, nBlue));
                 }
                 nDataSize += static_cast<sal_uLong>(nWidth) * 2;
             }
@@ -1001,13 +1004,14 @@ sal_uLong PictReader::ReadPixMapEtc( Bitmap &rBitmap, bool bBaseAddr, bool bColo
                            this case. Have a look at 32bit, there I changed the
                            encoding, so that it is used a straight forward array
                          */
+                        Scanline pScanline = pAcc->GetScanline(ny);
                         for (size_t i = 0; i < nCount; ++i)
                         {
                             pPict->ReadUInt16( nD );
                             nRed = static_cast<sal_uInt8>( nD >> 7 );
                             nGreen = static_cast<sal_uInt8>( nD >> 2 );
                             nBlue = static_cast<sal_uInt8>( nD << 3 );
-                            pAcc->SetPixel( ny, nx++, BitmapColor( nRed, nGreen, nBlue ) );
+                            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nRed, nGreen, nBlue));
                         }
                     }
                     else
@@ -1021,9 +1025,10 @@ sal_uLong PictReader::ReadPixMapEtc( Bitmap &rBitmap, bool bBaseAddr, bool bColo
                         nRed = static_cast<sal_uInt8>( nD >> 7 );
                         nGreen = static_cast<sal_uInt8>( nD >> 2 );
                         nBlue = static_cast<sal_uInt8>( nD << 3 );
+                        Scanline pScanline = pAcc->GetScanline(ny);
                         for (size_t i = 0; i < nCount; ++i)
                         {
-                            pAcc->SetPixel( ny, nx++, BitmapColor( nRed, nGreen, nBlue ) );
+                            pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(nRed, nGreen, nBlue));
                         }
                     }
                 }
@@ -1056,11 +1061,12 @@ sal_uLong PictReader::ReadPixMapEtc( Bitmap &rBitmap, bool bBaseAddr, bool bColo
 
             for (sal_uInt16 ny = 0; ny < nHeight; ++ny)
             {
+                Scanline pScanline = pAcc->GetScanline(ny);
                 for (sal_uInt16 nx = 0; nx < nWidth; ++nx)
                 {
                     sal_uInt8 nDummy;
                     pPict->ReadUChar( nDummy ).ReadUChar( nRed ).ReadUChar( nGreen ).ReadUChar( nBlue );
-                    pAcc->SetPixel( ny, nx, BitmapColor( nRed, nGreen, nBlue) );
+                    pAcc->SetPixelOnData(pScanline, nx, BitmapColor(nRed, nGreen, nBlue));
                 }
                 nDataSize += static_cast<sal_uLong>(nWidth) * 4;
             }
@@ -1080,10 +1086,11 @@ sal_uLong PictReader::ReadPixMapEtc( Bitmap &rBitmap, bool bBaseAddr, bool bColo
 
             for (sal_uInt16 ny = 0; ny < nHeight; ++ny)
             {
+                Scanline pScanline = pAcc->GetScanline(ny);
                 for (sal_uInt16 nx = 0; nx < nWidth; ++nx)
                 {
                     pPict->ReadUChar( nRed ).ReadUChar( nGreen ).ReadUChar( nBlue );
-                    pAcc->SetPixel( ny, nx, BitmapColor( nRed, nGreen, nBlue ) );
+                    pAcc->SetPixelOnData(pScanline, nx, BitmapColor(nRed, nGreen, nBlue));
                 }
                 nDataSize += static_cast<sal_uLong>(nWidth) * 3;
             }
@@ -1149,8 +1156,9 @@ sal_uLong PictReader::ReadPixMapEtc( Bitmap &rBitmap, bool bBaseAddr, bool bColo
                     sal_uInt8* pTmp = aScanline.data();
                     if ( nCmpCount == 4 )
                         pTmp += nWidth;
+                    Scanline pScanline = pAcc->GetScanline(ny);
                     for (sal_uInt16 nx = 0; nx < nWidth; pTmp++)
-                        pAcc->SetPixel( ny, nx++, BitmapColor( *pTmp, pTmp[ nWidth ], pTmp[ 2 * nWidth ] ) );
+                        pAcc->SetPixelOnData(pScanline, nx++, BitmapColor(*pTmp, pTmp[ nWidth ], pTmp[ 2 * nWidth ]));
                     nDataSize += static_cast<sal_uLong>(nByteCount);
                     pPict->Seek( nSrcBitsPos + static_cast<sal_uLong>(nByteCount) );
                 }
diff --git a/filter/source/graphicfilter/itiff/itiff.cxx b/filter/source/graphicfilter/itiff/itiff.cxx
index ed80d69dc72a..6e7bb2461eac 100644
--- a/filter/source/graphicfilter/itiff/itiff.cxx
+++ b/filter/source/graphicfilter/itiff/itiff.cxx
@@ -789,6 +789,10 @@ bool TIFFReader::ConvertScanline(sal_Int32 nY)
         {
             sal_uInt8* pt = getMapData(0);
 
+            Scanline pMaskScanLine = nullptr;
+            if (nSamplesPerPixel >= 4 && xMaskAcc)
+                pMaskScanLine = xMaskAcc->GetScanline(nY);
+
             // are the values being saved as difference?
             if ( 2 == nPredictor )
             {
@@ -801,11 +805,11 @@ bool TIFFReader::ConvertScanline(sal_Int32 nY)
                     nLRed = nLRed + pt[ 0 ];
                     nLGreen = nLGreen + pt[ 1 ];
                     nLBlue = nLBlue + pt[ 2 ];
-                    pAcc->SetPixel( nY, nx, Color( nLRed, nLGreen, nLBlue ) );
-                    if (nSamplesPerPixel >= 4 && xMaskAcc)
+                    pAcc->SetPixelOnData(pScanLine, nx, Color(nLRed, nLGreen, nLBlue));
+                    if (pMaskScanLine)
                     {
                         nLAlpha = nLAlpha + pt[ 3 ];
-                        xMaskAcc->SetPixel( nY, nx, BitmapColor(~nLAlpha) );
+                        xMaskAcc->SetPixelOnData(pMaskScanLine, nx, BitmapColor(~nLAlpha));
                     }
                 }
             }
@@ -813,11 +817,11 @@ bool TIFFReader::ConvertScanline(sal_Int32 nY)
             {
                 for (sal_Int32 nx = 0; nx < nImageWidth; nx++, pt += nSamplesPerPixel)
                 {
-                    pAcc->SetPixel( nY, nx, Color( pt[0], pt[1], pt[2] ) );
-                    if (nSamplesPerPixel >= 4 && xMaskAcc)
+                    pAcc->SetPixelOnData(pScanLine, nx, Color(pt[0], pt[1], pt[2]));
+                    if (pMaskScanLine)
                     {
                         sal_uInt8 nAlpha = pt[3];
-                        xMaskAcc->SetPixel( nY, nx, BitmapColor(~nAlpha) );
+                        xMaskAcc->SetPixelOnData(pMaskScanLine, nx, BitmapColor(~nAlpha));
                     }
                 }
             }
@@ -841,7 +845,7 @@ bool TIFFReader::ConvertScanline(sal_Int32 nY)
                         nGreen = GetBits( getMapData(1), nx * nBitsPerSample, nBitsPerSample );
                         nBlue = GetBits( getMapData(2), nx * nBitsPerSample, nBitsPerSample );
                     }
-                    pAcc->SetPixel( nY, nx, Color( static_cast<sal_uInt8>( nRed - nMinMax ), static_cast<sal_uInt8>( nGreen - nMinMax ), static_cast<sal_uInt8>(nBlue - nMinMax) ) );
+                    pAcc->SetPixelOnData(pScanLine, nx, Color(static_cast<sal_uInt8>(nRed - nMinMax), static_cast<sal_uInt8>(nGreen - nMinMax), static_cast<sal_uInt8>(nBlue - nMinMax)));
                 }
             }
         }
@@ -867,7 +871,7 @@ bool TIFFReader::ConvertScanline(sal_Int32 nY)
                     nRed = 255 - static_cast<sal_uInt8>( nRed - nMinMax );
                     nGreen = 255 - static_cast<sal_uInt8>( nGreen - nMinMax );
                     nBlue = 255 - static_cast<sal_uInt8>( nBlue - nMinMax );
-                    pAcc->SetPixel( nY, nx, Color( static_cast<sal_uInt8>(nRed), static_cast<sal_uInt8>(nGreen), static_cast<sal_uInt8>(nBlue) ) );
+                    pAcc->SetPixelOnData(pScanLine, nx, Color(static_cast<sal_uInt8>(nRed), static_cast<sal_uInt8>(nGreen), static_cast<sal_uInt8>(nBlue)));
                 }
             }
         }
@@ -909,7 +913,7 @@ bool TIFFReader::ConvertScanline(sal_Int32 nY)
                                 255L/static_cast<sal_Int32>(nMaxSampleValue-nMinSampleValue) ) ));
                     nBlue = static_cast<sal_uInt8>(std::max( 0L, 255L - ( ( static_cast<sal_Int32>(nSamp[ 2 ]) + nBlack - ( static_cast<sal_Int32>(nMinSampleValue) << 1 ) ) *
                                 255L/static_cast<sal_Int32>(nMaxSampleValue-nMinSampleValue) ) ));
-                    pAcc->SetPixel( nY, nx, Color ( static_cast<sal_uInt8>(nRed), static_cast<sal_uInt8>(nGreen), static_cast<sal_uInt8>(nBlue) ) );
+                    pAcc->SetPixelOnData(pScanLine, nx, Color(static_cast<sal_uInt8>(nRed), static_cast<sal_uInt8>(nGreen), static_cast<sal_uInt8>(nBlue)));
                 }
             }
         }
diff --git a/filter/source/msfilter/msdffimp.cxx b/filter/source/msfilter/msdffimp.cxx
index f840ee3fce62..b07351a3389e 100644
--- a/filter/source/msfilter/msdffimp.cxx
+++ b/filter/source/msfilter/msdffimp.cxx
@@ -1117,6 +1117,7 @@ void ApplyRectangularGradientAsBitmap( const SvxMSDffManager& rManager, SvStream
         {
             for ( long nY = 0; nY < aBitmapSizePixel.Height(); nY++ )
             {
+                Scanline pScanline = pAcc->GetScanline(nY);
                 for ( long nX = 0; nX < aBitmapSizePixel.Width(); nX++ )
                 {
                     double fX = static_cast< double >( nX ) / aBitmapSizePixel.Width();
@@ -1233,7 +1234,7 @@ void ApplyRectangularGradientAsBitmap( const SvxMSDffManager& rManager, SvStream
                     if ( nBlue > 255 )
                         nBlue = 255;
 
-                    pAcc->SetPixel( nY, nX, BitmapColor( static_cast< sal_Int8 >( nRed ), static_cast< sal_Int8 >( nGreen ), static_cast< sal_Int8 >( nBlue ) ) );
+                    pAcc->SetPixelOnData(pScanline, nX, BitmapColor(static_cast<sal_Int8>(nRed), static_cast<sal_Int8>(nGreen), static_cast<sal_Int8>(nBlue)));
                 }
             }
             Bitmap::ReleaseAccess( pAcc );
@@ -1376,6 +1377,7 @@ void DffPropertyReader::ApplyFillAttributes( SvStream& rIn, SfxItemSet& rSet, co
 
                                 for (long y = 0; y < pWrite->Height(); ++y)
                                 {
+                                    Scanline pScanline = pWrite->GetScanline(y);
                                     for (long x = 0; x < pWrite->Width(); ++x)
                                     {
                                         Color aReadColor;
@@ -1385,9 +1387,9 @@ void DffPropertyReader::ApplyFillAttributes( SvStream& rIn, SfxItemSet& rSet, co
                                             aReadColor = pRead->GetPixel(y, x);
 
                                         if (aReadColor.GetColor() == 0)
-                                            pWrite->SetPixel(y, x, aCol2);
+                                            pWrite->SetPixelOnData(pScanline, x, aCol2);
                                         else
-                                            pWrite->SetPixel(y, x, aCol1);
+                                            pWrite->SetPixelOnData(pScanline, x, aCol1);
                                     }
                                 }
                             }