/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 *
 * This file incorporates work covered by the following license notice:
 *
 *   Licensed to the Apache Software Foundation (ASF) under one or more
 *   contributor license agreements. See the NOTICE file distributed
 *   with this work for additional information regarding copyright
 *   ownership. The ASF licenses this file to you under the Apache
 *   License, Version 2.0 (the "License"); you may not use this file
 *   except in compliance with the License. You may obtain a copy of
 *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
 */

#include <config_features.h>

#include <sal/log.hxx>
#include <osl/diagnose.h>
#include <tools/helpers.hxx>

#include <vcl/bitmap.hxx>
#include <vcl/bitmapex.hxx>
#include <vcl/outdev.hxx>

#include <svdata.hxx>
#include <salinst.hxx>
#include <salbmp.hxx>
#include <bitmapwriteaccess.hxx>
#if HAVE_FEATURE_SKIA
#include <vcl/skia/SkiaHelper.hxx>
#endif
#include <vcl/BitmapMonochromeFilter.hxx>

#include <svdata.hxx>
#include <salinst.hxx>
#include <salbmp.hxx>
#include <BitmapScaleSuperFilter.hxx>
#include <BitmapScaleConvolutionFilter.hxx>
#include <BitmapFastScaleFilter.hxx>
#include <BitmapInterpolateScaleFilter.hxx>
#include <bitmapwriteaccess.hxx>
#include <bitmap/impoctree.hxx>
#include <bitmap/Octree.hxx>

#include "impvect.hxx"
#include "floyd.hxx"

#include <math.h>
#include <algorithm>
#include <memory>

#ifdef DBG_UTIL
#include <cstdlib>
#include <tools/stream.hxx>
#include <vcl/graphicfilter.hxx>
#endif

Bitmap::Bitmap()
{
}

Bitmap::Bitmap(const Bitmap& rBitmap)
    : mxSalBmp(rBitmap.mxSalBmp)
    , maPrefMapMode(rBitmap.maPrefMapMode)
    , maPrefSize(rBitmap.maPrefSize)
{
}

Bitmap::Bitmap(std::shared_ptr<SalBitmap> const & pSalBitmap)
    : mxSalBmp(pSalBitmap)
    , maPrefMapMode(MapMode(MapUnit::MapPixel))
    , maPrefSize(mxSalBmp->GetSize())
{
}

Bitmap::Bitmap( const Size& rSizePixel, sal_uInt16 nBitCount, const BitmapPalette* pPal )
{
    if (!(rSizePixel.Width() && rSizePixel.Height()))
        return;

    BitmapPalette   aPal;
    BitmapPalette*  pRealPal = nullptr;

    if( nBitCount <= 8 )
    {
        if( !pPal )
        {
            if( 1 == nBitCount )
            {
                aPal.SetEntryCount( 2 );
                aPal[ 0 ] = COL_BLACK;
                aPal[ 1 ] = COL_WHITE;
            }
            else if( ( 4 == nBitCount ) || ( 8 == nBitCount ) )
            {
                aPal.SetEntryCount( 1 << nBitCount );
                aPal[ 0 ] = COL_BLACK;
                aPal[ 1 ] = COL_BLUE;
                aPal[ 2 ] = COL_GREEN;
                aPal[ 3 ] = COL_CYAN;
                aPal[ 4 ] = COL_RED;
                aPal[ 5 ] = COL_MAGENTA;
                aPal[ 6 ] = COL_BROWN;
                aPal[ 7 ] = COL_GRAY;
                aPal[ 8 ] = COL_LIGHTGRAY;
                aPal[ 9 ] = COL_LIGHTBLUE;
                aPal[ 10 ] = COL_LIGHTGREEN;
                aPal[ 11 ] = COL_LIGHTCYAN;
                aPal[ 12 ] = COL_LIGHTRED;
                aPal[ 13 ] = COL_LIGHTMAGENTA;
                aPal[ 14 ] = COL_YELLOW;
                aPal[ 15 ] = COL_WHITE;

                // Create dither palette
                if( 8 == nBitCount )
                {
                    sal_uInt16 nActCol = 16;

                    for( sal_uInt16 nB = 0; nB < 256; nB += 51 )
                        for( sal_uInt16 nG = 0; nG < 256; nG += 51 )
                            for( sal_uInt16 nR = 0; nR < 256; nR += 51 )
                                aPal[ nActCol++ ] = BitmapColor( static_cast<sal_uInt8>(nR), static_cast<sal_uInt8>(nG), static_cast<sal_uInt8>(nB) );

                    // Set standard Office colors
                    aPal[ nActCol++ ] = BitmapColor( 0, 184, 255 );
                }
            }
        }
        else
            pRealPal = const_cast<BitmapPalette*>(pPal);
    }

    mxSalBmp = ImplGetSVData()->mpDefInst->CreateSalBitmap();
    mxSalBmp->Create( rSizePixel, nBitCount, pRealPal ? *pRealPal : aPal );
}

#ifdef DBG_UTIL

namespace
{
void savePNG(const OUString& sWhere, const Bitmap& rBmp)
{
    SvFileStream aStream(sWhere, StreamMode::WRITE | StreamMode::TRUNC);
    GraphicFilter& rFilter = GraphicFilter::GetGraphicFilter();
    rFilter.compressAsPNG(BitmapEx(rBmp), aStream);
}
}

#endif

Bitmap::~Bitmap()
{
#ifdef DBG_UTIL
    // VCL_DUMP_BMP_PATH should be like C:/bmpDump.png or ~/bmpDump.png
    static const OUString sDumpPath(OUString::createFromAscii(std::getenv("VCL_DUMP_BMP_PATH")));
    // Stepping into the dtor of a bitmap you need, and setting the volatile variable to true in
    // debugger, would dump the bitmap in question
    static volatile bool save(false);
    if (!sDumpPath.isEmpty() && save)
    {
        save = false;
        savePNG(sDumpPath, *this);
    }
#endif
}

const BitmapPalette& Bitmap::GetGreyPalette( int nEntries )
{
    // Create greyscale palette with 2, 4, 16 or 256 entries
    switch (nEntries)
    {
        case 2:
        {
            static const BitmapPalette aGreyPalette2 = [] {
                BitmapPalette aPalette(2);
                aPalette[0] = BitmapColor(0, 0, 0);
                aPalette[1] = BitmapColor(255, 255, 255);
                return aPalette;
            }();

            return aGreyPalette2;
        }
        case 4:
        {
            static const BitmapPalette aGreyPalette4 = [] {
                BitmapPalette aPalette(4);
                aPalette[0] = BitmapColor(0, 0, 0);
                aPalette[1] = BitmapColor(85, 85, 85);
                aPalette[2] = BitmapColor(170, 170, 170);
                aPalette[3] = BitmapColor(255, 255, 255);
                return aPalette;
            }();

            return aGreyPalette4;
        }
        case 16:
        {
            static const BitmapPalette aGreyPalette16 = [] {
                sal_uInt8 cGrey = 0;
                sal_uInt8 const cGreyInc = 17;

                BitmapPalette aPalette(16);

                for (sal_uInt16 i = 0; i < 16; ++i, cGrey += cGreyInc)
                    aPalette[i] = BitmapColor(cGrey, cGrey, cGrey);

                return aPalette;
            }();

            return aGreyPalette16;
        }
        case 256:
        {
            static const BitmapPalette aGreyPalette256 = [] {
                BitmapPalette aPalette(256);

                for (sal_uInt16 i = 0; i < 256; ++i)
                    aPalette[i] = BitmapColor(static_cast<sal_uInt8>(i), static_cast<sal_uInt8>(i),
                                              static_cast<sal_uInt8>(i));

                return aPalette;
            }();

            return aGreyPalette256;
        }
    }
    OSL_FAIL("Bitmap::GetGreyPalette: invalid entry count (2/4/16/256 allowed)");
    return GetGreyPalette(2);
}

bool BitmapPalette::IsGreyPaletteAny() const
{
    const int nEntryCount = GetEntryCount();
    if( !nEntryCount ) // NOTE: an empty palette means 1:1 mapping
        return true;
    // See above: only certain entry values will result in a valid call to GetGreyPalette
    if( nEntryCount == 2 || nEntryCount == 4 || nEntryCount == 16 || nEntryCount == 256 )
    {
        const BitmapPalette& rGreyPalette = Bitmap::GetGreyPalette( nEntryCount );
        if( rGreyPalette == *this )
            return true;
    }

    bool bRet = false;
    // TODO: is it worth to compare the entries for the general case?
    if (nEntryCount == 2)
    {
       const BitmapColor& rCol0(maBitmapColor[0]);
       const BitmapColor& rCol1(maBitmapColor[1]);
       bRet = rCol0.GetRed() == rCol0.GetGreen() && rCol0.GetRed() == rCol0.GetBlue() &&
              rCol1.GetRed() == rCol1.GetGreen() && rCol1.GetRed() == rCol1.GetBlue();
    }
    return bRet;
}

bool BitmapPalette::IsGreyPalette8Bit() const
{
    const int nEntryCount = GetEntryCount();
    if( !nEntryCount ) // NOTE: an empty palette means 1:1 mapping
        return true;
    if( nEntryCount != 256 )
        return false;
    for (sal_uInt16 i = 0; i < 256; ++i)
    {
        if( maBitmapColor[i] != BitmapColor(i, i, i))
            return false;
    }
    return true;
}

Bitmap& Bitmap::operator=( const Bitmap& rBitmap )
{
    if (this == &rBitmap)
        return *this;

    maPrefSize = rBitmap.maPrefSize;
    maPrefMapMode = rBitmap.maPrefMapMode;
    mxSalBmp = rBitmap.mxSalBmp;

    return *this;
}

Bitmap& Bitmap::operator=( Bitmap&& rBitmap ) noexcept
{
    maPrefSize = std::move(rBitmap.maPrefSize);
    maPrefMapMode = std::move(rBitmap.maPrefMapMode);
    mxSalBmp = std::move(rBitmap.mxSalBmp);

    return *this;
}

bool Bitmap::operator==( const Bitmap& rBmp ) const
{
    if (rBmp.mxSalBmp == mxSalBmp) // Includes both are nullptr
        return true;
    if (!rBmp.mxSalBmp || !mxSalBmp)
        return false;
    if (rBmp.mxSalBmp->GetSize() != mxSalBmp->GetSize() ||
        rBmp.mxSalBmp->GetBitCount() != mxSalBmp->GetBitCount())
        return false;
    BitmapChecksum aChecksum1, aChecksum2;
    rBmp.mxSalBmp->GetChecksum(aChecksum1);
    mxSalBmp->GetChecksum(aChecksum2);
    // If the bitmaps can't calculate a checksum, best to regard them as different.
    if (aChecksum1 == 0 || aChecksum2 == 0)
        return false;
    return aChecksum1 == aChecksum2;
}

void Bitmap::SetEmpty()
{
    maPrefMapMode = MapMode();
    maPrefSize = Size();
    mxSalBmp.reset();
}

Size Bitmap::GetSizePixel() const
{
    return( mxSalBmp ? mxSalBmp->GetSize() : Size() );
}

sal_uInt16 Bitmap::GetBitCount() const
{
    if (!mxSalBmp)
        return 0;

    sal_uInt16 nBitCount = mxSalBmp->GetBitCount();
    if (nBitCount <= 1)
        return 1;
    if (nBitCount <= 4)
        return 4;
    if (nBitCount <= 8)
        return 8;
    if (nBitCount <= 24)
        return 24;
    if (nBitCount <= 32)
        return 32;
    return 0;
}

bool Bitmap::HasGreyPaletteAny() const
{
    const sal_uInt16    nBitCount = GetBitCount();
    bool            bRet = nBitCount == 1;

    ScopedInfoAccess pIAcc(const_cast<Bitmap&>(*this));

    if( pIAcc )
    {
        bRet = pIAcc->HasPalette() && pIAcc->GetPalette().IsGreyPaletteAny();
    }

    return bRet;
}

bool Bitmap::HasGreyPalette8Bit() const
{
    bool            bRet = false;
    ScopedInfoAccess pIAcc(const_cast<Bitmap&>(*this));

    if( pIAcc )
    {
        bRet = pIAcc->HasPalette() && pIAcc->GetPalette().IsGreyPalette8Bit();
    }

    return bRet;
}

BitmapChecksum Bitmap::GetChecksum() const
{
    BitmapChecksum nRet = 0;

    if( mxSalBmp )
    {
        mxSalBmp->GetChecksum(nRet);

        if (!nRet)
        {
            // nRet == 0 => probably, we were not able to acquire
            // the buffer in SalBitmap::updateChecksum;
            // so, we need to update the imp bitmap for this bitmap instance
            // as we do in BitmapInfoAccess::ImplCreate
            std::shared_ptr<SalBitmap> xNewImpBmp(ImplGetSVData()->mpDefInst->CreateSalBitmap());
            if (xNewImpBmp->Create(*mxSalBmp, GetBitCount()))
            {
                Bitmap* pThis = const_cast<Bitmap*>(this);
                pThis->mxSalBmp = xNewImpBmp;
                mxSalBmp->GetChecksum(nRet);
            }
        }
    }

    return nRet;
}

void Bitmap::ImplMakeUnique()
{
    if (mxSalBmp && mxSalBmp.use_count() > 1)
    {
        std::shared_ptr<SalBitmap> xOldImpBmp = mxSalBmp;
        mxSalBmp = ImplGetSVData()->mpDefInst->CreateSalBitmap();
        (void)mxSalBmp->Create(*xOldImpBmp);
    }
}

void Bitmap::ReassignWithSize(const Bitmap& rBitmap)
{
    const Size aOldSizePix(GetSizePixel());
    const Size aNewSizePix(rBitmap.GetSizePixel());
    const MapMode aOldMapMode(maPrefMapMode);
    Size aNewPrefSize;

    if ((aOldSizePix != aNewSizePix) && aOldSizePix.Width() && aOldSizePix.Height())
    {
        aNewPrefSize.setWidth(FRound(maPrefSize.Width() * aNewSizePix.Width() / aOldSizePix.Width()));
        aNewPrefSize.setHeight(FRound(maPrefSize.Height() * aNewSizePix.Height() / aOldSizePix.Height()));
    }
    else
    {
        aNewPrefSize = maPrefSize;
    }

    *this = rBitmap;

    maPrefSize = aNewPrefSize;
    maPrefMapMode = aOldMapMode;
}


void Bitmap::ImplSetSalBitmap(const std::shared_ptr<SalBitmap>& xImpBmp)
{
    mxSalBmp = xImpBmp;
}

BitmapInfoAccess* Bitmap::AcquireInfoAccess()
{
    std::unique_ptr<BitmapInfoAccess> pInfoAccess(new BitmapInfoAccess( *this ));

    if( !*pInfoAccess )
    {
        return nullptr;
    }

    return pInfoAccess.release();
}

BitmapReadAccess* Bitmap::AcquireReadAccess()
{
    std::unique_ptr<BitmapReadAccess> pReadAccess(new BitmapReadAccess( *this ));

    if( !*pReadAccess )
    {
        return nullptr;
    }

    return pReadAccess.release();
}

BitmapWriteAccess* Bitmap::AcquireWriteAccess()
{
    std::unique_ptr<BitmapWriteAccess> pWriteAccess(new BitmapWriteAccess( *this ));

    if( !*pWriteAccess )
    {
        return nullptr;
    }

    return pWriteAccess.release();
}

void Bitmap::ReleaseAccess( BitmapInfoAccess* pBitmapAccess )
{
    delete pBitmapAccess;
}

bool Bitmap::Crop( const tools::Rectangle& rRectPixel )
{
    const Size          aSizePix( GetSizePixel() );
    tools::Rectangle           aRect( rRectPixel );
    bool                bRet = false;

    aRect.Intersection( tools::Rectangle( Point(), aSizePix ) );

    if( !aRect.IsEmpty() && aSizePix != aRect.GetSize())
    {
        ScopedReadAccess pReadAcc(*this);

        if( pReadAcc )
        {
            const tools::Rectangle     aNewRect( Point(), aRect.GetSize() );
            Bitmap              aNewBmp( aNewRect.GetSize(), GetBitCount(), &pReadAcc->GetPalette() );
            BitmapScopedWriteAccess pWriteAcc(aNewBmp);

            if( pWriteAcc )
            {
                const tools::Long nOldX = aRect.Left();
                const tools::Long nOldY = aRect.Top();
                const tools::Long nNewWidth = aNewRect.GetWidth();
                const tools::Long nNewHeight = aNewRect.GetHeight();

                for( tools::Long nY = 0, nY2 = nOldY; nY < nNewHeight; nY++, nY2++ )
                {
                    Scanline pScanline = pWriteAcc->GetScanline(nY);
                    Scanline pScanlineRead = pReadAcc->GetScanline(nY2);
                    for( tools::Long nX = 0, nX2 = nOldX; nX < nNewWidth; nX++, nX2++ )
                        pWriteAcc->SetPixelOnData( pScanline, nX, pReadAcc->GetPixelFromData( pScanlineRead, nX2 ) );
                }

                pWriteAcc.reset();
                bRet = true;
            }

            pReadAcc.reset();

            if( bRet )
                ReassignWithSize( aNewBmp );
        }
    }

    return bRet;
};

bool Bitmap::CopyPixel( const tools::Rectangle& rRectDst,
                        const tools::Rectangle& rRectSrc, const Bitmap* pBmpSrc )
{
    const Size  aSizePix( GetSizePixel() );
    tools::Rectangle   aRectDst( rRectDst );
    bool        bRet = false;

    aRectDst.Intersection( tools::Rectangle( Point(), aSizePix ) );

    if( !aRectDst.IsEmpty() )
    {
        if( pBmpSrc && ( pBmpSrc->mxSalBmp != mxSalBmp ) )
        {
            Bitmap*         pSrc = const_cast<Bitmap*>(pBmpSrc);
            const Size      aCopySizePix( pSrc->GetSizePixel() );
            tools::Rectangle       aRectSrc( rRectSrc );
            const sal_uInt16    nSrcBitCount = pBmpSrc->GetBitCount();
            const sal_uInt16    nDstBitCount = GetBitCount();

            if( nSrcBitCount > nDstBitCount )
            {
                int nNextIndex = 0;

                if (nSrcBitCount == 24)
                    Convert( BmpConversion::N24Bit );
                else if (nSrcBitCount == 8)
                {
                    Convert( BmpConversion::N8BitColors );
                    nNextIndex = 16;
                }
                else if (nSrcBitCount == 4)
                {
                    Convert( BmpConversion::N4BitColors );
                    nNextIndex = 2;
                }

                if( nNextIndex )
                {
                    ScopedReadAccess    pSrcAcc(*pSrc);
                    BitmapScopedWriteAccess pDstAcc(*this);

                    if( pSrcAcc && pDstAcc )
                    {
                        const int nSrcCount = pDstAcc->GetPaletteEntryCount();
                        const int nDstCount = 1 << nDstBitCount;

                        for (int i = 0; ( i < nSrcCount ) && ( nNextIndex < nSrcCount ); ++i)
                        {
                            const BitmapColor& rSrcCol = pSrcAcc->GetPaletteColor( static_cast<sal_uInt16>(i) );

                            bool bFound = false;

                            for (int j = 0; j < nDstCount; ++j)
                            {
                                if( rSrcCol == pDstAcc->GetPaletteColor( static_cast<sal_uInt16>(j) ) )
                                {
                                    bFound = true;
                                    break;
                                }
                            }

                            if( !bFound )
                                pDstAcc->SetPaletteColor( static_cast<sal_uInt16>(nNextIndex++), rSrcCol );
                        }
                    }
                }
            }

            aRectSrc.Intersection( tools::Rectangle( Point(), aCopySizePix ) );

            if( !aRectSrc.IsEmpty() )
            {
                ScopedReadAccess pReadAcc(*pSrc);

                if( pReadAcc )
                {
                    BitmapScopedWriteAccess pWriteAcc(*this);

                    if( pWriteAcc )
                    {
                        const tools::Long  nWidth = std::min( aRectSrc.GetWidth(), aRectDst.GetWidth() );
                        const tools::Long  nHeight = std::min( aRectSrc.GetHeight(), aRectDst.GetHeight() );
                        const tools::Long  nSrcEndX = aRectSrc.Left() + nWidth;
                        const tools::Long  nSrcEndY = aRectSrc.Top() + nHeight;
                        tools::Long        nDstY = aRectDst.Top();

                        if( pReadAcc->HasPalette() && pWriteAcc->HasPalette() )
                        {
                            const sal_uInt16    nCount = pReadAcc->GetPaletteEntryCount();
                            std::unique_ptr<sal_uInt8[]> pMap(new sal_uInt8[ nCount ]);

                            // Create index map for the color table, as the bitmap should be copied
                            // retaining it's color information relatively well
                            for( sal_uInt16 i = 0; i < nCount; i++ )
                                pMap[ i ] = static_cast<sal_uInt8>(pWriteAcc->GetBestPaletteIndex( pReadAcc->GetPaletteColor( i ) ));

                            for( tools::Long nSrcY = aRectSrc.Top(); nSrcY < nSrcEndY; nSrcY++, nDstY++ )
                            {
                                Scanline pScanline = pWriteAcc->GetScanline(nDstY);
                                Scanline pScanlineRead = pReadAcc->GetScanline(nSrcY);
                                for( tools::Long nSrcX = aRectSrc.Left(), nDstX = aRectDst.Left(); nSrcX < nSrcEndX; nSrcX++, nDstX++ )
                                    pWriteAcc->SetPixelOnData( pScanline, nDstX, BitmapColor( pMap[ pReadAcc->GetIndexFromData( pScanlineRead, nSrcX ) ] ));
                            }
                        }
                        else if( pReadAcc->HasPalette() )
                        {
                            for( tools::Long nSrcY = aRectSrc.Top(); nSrcY < nSrcEndY; nSrcY++, nDstY++ )
                            {
                                Scanline pScanline = pWriteAcc->GetScanline(nDstY);
                                Scanline pScanlineRead = pReadAcc->GetScanline(nSrcY);
                                for( tools::Long nSrcX = aRectSrc.Left(), nDstX = aRectDst.Left(); nSrcX < nSrcEndX; nSrcX++, nDstX++ )
                                    pWriteAcc->SetPixelOnData( pScanline, nDstX, pReadAcc->GetPaletteColor( pReadAcc->GetIndexFromData( pScanlineRead, nSrcX ) ) );
                            }
                        }
                        else
                            for( tools::Long nSrcY = aRectSrc.Top(); nSrcY < nSrcEndY; nSrcY++, nDstY++ )
                            {
                                Scanline pScanline = pWriteAcc->GetScanline(nDstY);
                                Scanline pScanlineRead = pReadAcc->GetScanline(nSrcY);
                                for( tools::Long nSrcX = aRectSrc.Left(), nDstX = aRectDst.Left(); nSrcX < nSrcEndX; nSrcX++, nDstX++ )
                                    pWriteAcc->SetPixelOnData( pScanline, nDstX, pReadAcc->GetPixelFromData( pScanlineRead, nSrcX ) );
                            }

                        pWriteAcc.reset();
                        bRet = ( nWidth > 0 ) && ( nHeight > 0 );
                    }

                    pReadAcc.reset();
                }
            }
        }
        else
        {
            tools::Rectangle aRectSrc( rRectSrc );

            aRectSrc.Intersection( tools::Rectangle( Point(), aSizePix ) );

            if( !aRectSrc.IsEmpty() && ( aRectSrc != aRectDst ) )
            {
                BitmapScopedWriteAccess   pWriteAcc(*this);

                if( pWriteAcc )
                {
                    const tools::Long  nWidth = std::min( aRectSrc.GetWidth(), aRectDst.GetWidth() );
                    const tools::Long  nHeight = std::min( aRectSrc.GetHeight(), aRectDst.GetHeight() );
                    const tools::Long  nSrcX = aRectSrc.Left();
                    const tools::Long  nSrcY = aRectSrc.Top();
                    const tools::Long  nSrcEndX1 = nSrcX + nWidth - 1;
                    const tools::Long  nSrcEndY1 = nSrcY + nHeight - 1;
                    const tools::Long  nDstX = aRectDst.Left();
                    const tools::Long  nDstY = aRectDst.Top();
                    const tools::Long  nDstEndX1 = nDstX + nWidth - 1;
                    const tools::Long  nDstEndY1 = nDstY + nHeight - 1;

                    if( ( nDstX <= nSrcX ) && ( nDstY <= nSrcY ) )
                    {
                        for( tools::Long nY = nSrcY, nYN = nDstY; nY <= nSrcEndY1; nY++, nYN++ )
                        {
                            Scanline pScanline = pWriteAcc->GetScanline(nYN);
                            Scanline pScanlineSrc = pWriteAcc->GetScanline(nY);
                            for( tools::Long nX = nSrcX, nXN = nDstX; nX <= nSrcEndX1; nX++, nXN++ )
                                pWriteAcc->SetPixelOnData( pScanline, nXN, pWriteAcc->GetPixelFromData( pScanlineSrc, nX ) );
                        }
                    }
                    else if( ( nDstX <= nSrcX ) && ( nDstY >= nSrcY ) )
                    {
                        for( tools::Long nY = nSrcEndY1, nYN = nDstEndY1; nY >= nSrcY; nY--, nYN-- )
                        {
                            Scanline pScanline = pWriteAcc->GetScanline(nYN);
                            Scanline pScanlineSrc = pWriteAcc->GetScanline(nY);
                            for( tools::Long nX = nSrcX, nXN = nDstX; nX <= nSrcEndX1; nX++, nXN++ )
                                pWriteAcc->SetPixelOnData( pScanline, nXN, pWriteAcc->GetPixelFromData( pScanlineSrc, nX ) );
                        }
                    }
                    else if( ( nDstX >= nSrcX ) && ( nDstY <= nSrcY ) )
                    {
                        for( tools::Long nY = nSrcY, nYN = nDstY; nY <= nSrcEndY1; nY++, nYN++ )
                        {
                            Scanline pScanline = pWriteAcc->GetScanline(nYN);
                            Scanline pScanlineSrc = pWriteAcc->GetScanline(nY);
                            for( tools::Long nX = nSrcEndX1, nXN = nDstEndX1; nX >= nSrcX; nX--, nXN-- )
                                pWriteAcc->SetPixelOnData( pScanline, nXN, pWriteAcc->GetPixelFromData( pScanlineSrc, nX ) );
                        }
                    }
                    else
                    {
                        for( tools::Long nY = nSrcEndY1, nYN = nDstEndY1; nY >= nSrcY; nY--, nYN-- )
                        {
                            Scanline pScanline = pWriteAcc->GetScanline(nYN);
                            Scanline pScanlineSrc = pWriteAcc->GetScanline(nY);
                            for( tools::Long nX = nSrcEndX1, nXN = nDstEndX1; nX >= nSrcX; nX--, nXN-- )
                                pWriteAcc->SetPixelOnData( pScanline, nXN, pWriteAcc->GetPixelFromData( pScanlineSrc, nX ) );
                        }
                    }

                    pWriteAcc.reset();
                    bRet = true;
                }
            }
        }
    }

    return bRet;
}

bool Bitmap::CopyPixel_AlphaOptimized( const tools::Rectangle& rRectDst, const tools::Rectangle& rRectSrc,
                           const Bitmap* pBmpSrc )
{
    // Note: this code is copied from Bitmap::CopyPixel but avoids any palette lookups
    // This optimization is possible because the palettes of AlphaMasks are always identical (8bit GreyPalette, see ctor)
    const Size  aSizePix( GetSizePixel() );
    tools::Rectangle   aRectDst( rRectDst );
    bool        bRet = false;

    aRectDst.Intersection( tools::Rectangle( Point(), aSizePix ) );

    if( !aRectDst.IsEmpty() )
    {
        if( pBmpSrc && ( pBmpSrc->mxSalBmp != mxSalBmp ) )
        {
            Bitmap*         pSrc = const_cast<Bitmap*>(pBmpSrc);
            const Size      aCopySizePix( pSrc->GetSizePixel() );
            tools::Rectangle       aRectSrc( rRectSrc );

            aRectSrc.Intersection( tools::Rectangle( Point(), aCopySizePix ) );

            if( !aRectSrc.IsEmpty() )
            {
                ScopedReadAccess pReadAcc(*pSrc);

                if( pReadAcc )
                {
                    BitmapScopedWriteAccess pWriteAcc(*this);

                    if( pWriteAcc )
                    {
                        const tools::Long  nWidth = std::min( aRectSrc.GetWidth(), aRectDst.GetWidth() );
                        const tools::Long  nHeight = std::min( aRectSrc.GetHeight(), aRectDst.GetHeight() );
                        const tools::Long  nSrcEndX = aRectSrc.Left() + nWidth;
                        const tools::Long  nSrcEndY = aRectSrc.Top() + nHeight;
                        tools::Long        nDstY = aRectDst.Top();

                        for( tools::Long nSrcY = aRectSrc.Top(); nSrcY < nSrcEndY; nSrcY++, nDstY++)
                        {
                            Scanline pScanline = pWriteAcc->GetScanline(nDstY);
                            Scanline pScanlineRead = pReadAcc->GetScanline(nSrcY);
                            for( tools::Long nSrcX = aRectSrc.Left(), nDstX = aRectDst.Left(); nSrcX < nSrcEndX; nSrcX++, nDstX++ )
                                pWriteAcc->SetPixelOnData( pScanline, nDstX, pReadAcc->GetPixelFromData( pScanlineRead, nSrcX ) );
                        }

                        pWriteAcc.reset();
                        bRet = ( nWidth > 0 ) && ( nHeight > 0 );
                    }

                    pReadAcc.reset();
                }
            }
        }
        else
        {
            tools::Rectangle aRectSrc( rRectSrc );

            aRectSrc.Intersection( tools::Rectangle( Point(), aSizePix ) );

            if( !aRectSrc.IsEmpty() && ( aRectSrc != aRectDst ) )
            {
                BitmapScopedWriteAccess   pWriteAcc(*this);

                if( pWriteAcc )
                {
                    const tools::Long  nWidth = std::min( aRectSrc.GetWidth(), aRectDst.GetWidth() );
                    const tools::Long  nHeight = std::min( aRectSrc.GetHeight(), aRectDst.GetHeight() );
                    const tools::Long  nSrcX = aRectSrc.Left();
                    const tools::Long  nSrcY = aRectSrc.Top();
                    const tools::Long  nSrcEndX1 = nSrcX + nWidth - 1;
                    const tools::Long  nSrcEndY1 = nSrcY + nHeight - 1;
                    const tools::Long  nDstX = aRectDst.Left();
                    const tools::Long  nDstY = aRectDst.Top();
                    const tools::Long  nDstEndX1 = nDstX + nWidth - 1;
                    const tools::Long  nDstEndY1 = nDstY + nHeight - 1;

                    if( ( nDstX <= nSrcX ) && ( nDstY <= nSrcY ) )
                    {
                        for( tools::Long nY = nSrcY, nYN = nDstY; nY <= nSrcEndY1; nY++, nYN++ )
                        {
                            Scanline pScanline = pWriteAcc->GetScanline(nYN);
                            Scanline pScanlineSrc = pWriteAcc->GetScanline(nY);
                            for( tools::Long nX = nSrcX, nXN = nDstX; nX <= nSrcEndX1; nX++, nXN++ )
                                pWriteAcc->SetPixelOnData( pScanline, nXN, pWriteAcc->GetPixelFromData( pScanlineSrc, nX ) );
                        }
                    }
                    else if( ( nDstX <= nSrcX ) && ( nDstY >= nSrcY ) )
                    {
                        for( tools::Long nY = nSrcEndY1, nYN = nDstEndY1; nY >= nSrcY; nY--, nYN-- )
                        {
                            Scanline pScanline = pWriteAcc->GetScanline(nYN);
                            Scanline pScanlineSrc = pWriteAcc->GetScanline(nY);
                            for( tools::Long nX = nSrcX, nXN = nDstX; nX <= nSrcEndX1; nX++, nXN++ )
                                pWriteAcc->SetPixelOnData( pScanline, nXN, pWriteAcc->GetPixelFromData( pScanlineSrc, nX ) );
                        }
                    }
                    else if( ( nDstX >= nSrcX ) && ( nDstY <= nSrcY ) )
                    {
                        for( tools::Long nY = nSrcY, nYN = nDstY; nY <= nSrcEndY1; nY++, nYN++ )
                        {
                            Scanline pScanline = pWriteAcc->GetScanline(nYN);
                            Scanline pScanlineSrc = pWriteAcc->GetScanline(nY);
                            for( tools::Long nX = nSrcEndX1, nXN = nDstEndX1; nX >= nSrcX; nX--, nXN-- )
                                pWriteAcc->SetPixelOnData( pScanline, nXN, pWriteAcc->GetPixelFromData( pScanlineSrc, nX ) );
                        }
                    }
                    else
                    {
                        for( tools::Long nY = nSrcEndY1, nYN = nDstEndY1; nY >= nSrcY; nY--, nYN-- )
                        {
                            Scanline pScanline = pWriteAcc->GetScanline(nYN);
                            Scanline pScanlineSrc = pWriteAcc->GetScanline(nY);
                            for( tools::Long nX = nSrcEndX1, nXN = nDstEndX1; nX >= nSrcX; nX--, nXN-- )
                                pWriteAcc->SetPixelOnData( pScanline, nXN, pWriteAcc->GetPixelFromData( pScanlineSrc, nX ) );
                        }
                    }

                    pWriteAcc.reset();
                    bRet = true;
                }
            }
        }
    }

    return bRet;

}

bool Bitmap::Expand( sal_uLong nDX, sal_uLong nDY, const Color* pInitColor )
{
    bool bRet = false;

    if( nDX || nDY )
    {
        const Size          aSizePixel( GetSizePixel() );
        const tools::Long          nWidth = aSizePixel.Width();
        const tools::Long          nHeight = aSizePixel.Height();
        const Size          aNewSize( nWidth + nDX, nHeight + nDY );
        ScopedReadAccess    pReadAcc(*this);

        if( pReadAcc )
        {
            BitmapPalette       aBmpPal( pReadAcc->GetPalette() );
            Bitmap              aNewBmp( aNewSize, GetBitCount(), &aBmpPal );
            BitmapScopedWriteAccess pWriteAcc(aNewBmp);

            if( pWriteAcc )
            {
                BitmapColor aColor;
                const tools::Long  nNewX = nWidth;
                const tools::Long  nNewY = nHeight;
                const tools::Long  nNewWidth = pWriteAcc->Width();
                const tools::Long  nNewHeight = pWriteAcc->Height();
                tools::Long        nX;
                tools::Long        nY;

                if( pInitColor )
                    aColor = pWriteAcc->GetBestMatchingColor( *pInitColor );

                for( nY = 0; nY < nHeight; nY++ )
                {
                    pWriteAcc->CopyScanline( nY, *pReadAcc );

                    if( pInitColor && nDX )
                    {
                        Scanline pScanline = pWriteAcc->GetScanline(nY);
                        for( nX = nNewX; nX < nNewWidth; nX++ )
                            pWriteAcc->SetPixelOnData( pScanline, nX, aColor );
                    }
                }

                if( pInitColor && nDY )
                    for( nY = nNewY; nY < nNewHeight; nY++ )
                    {
                        Scanline pScanline = pWriteAcc->GetScanline(nY);
                        for( nX = 0; nX < nNewWidth; nX++ )
                            pWriteAcc->SetPixelOnData( pScanline, nX, aColor );
                    }

                pWriteAcc.reset();
                bRet = true;
            }

            pReadAcc.reset();

            if (bRet)
                ReassignWithSize(aNewBmp);
        }
    }

    return bRet;
}

Bitmap Bitmap::CreateDisplayBitmap( OutputDevice* pDisplay ) const
{
    Bitmap aDispBmp( *this );

    SalGraphics* pDispGraphics = pDisplay->GetGraphics();

    if( mxSalBmp && pDispGraphics )
    {
        std::shared_ptr<SalBitmap> xImpDispBmp(ImplGetSVData()->mpDefInst->CreateSalBitmap());
        if (xImpDispBmp->Create(*mxSalBmp, pDispGraphics))
            aDispBmp.ImplSetSalBitmap(xImpDispBmp);
    }

    return aDispBmp;
}

bool Bitmap::GetSystemData( BitmapSystemData& rData ) const
{
    return mxSalBmp && mxSalBmp->GetSystemData(rData);
}


bool Bitmap::Convert( BmpConversion eConversion )
{
    // try to convert in backend
    if (mxSalBmp)
    {
        // avoid large chunk of obsolete and hopefully rarely used conversions.
        if (eConversion == BmpConversion::N8BitNoConversion)
        {
            std::shared_ptr<SalBitmap> xImpBmp(ImplGetSVData()->mpDefInst->CreateSalBitmap());
            // frequently used conversion for creating alpha masks
            if (xImpBmp->Create(*mxSalBmp) && xImpBmp->InterpretAs8Bit())
            {
                ImplSetSalBitmap(xImpBmp);
                SAL_INFO( "vcl.opengl", "Ref count: " << mxSalBmp.use_count() );
                return true;
            }
        }
        if (eConversion == BmpConversion::N8BitGreys)
        {
            std::shared_ptr<SalBitmap> xImpBmp(ImplGetSVData()->mpDefInst->CreateSalBitmap());
            if (xImpBmp->Create(*mxSalBmp) && xImpBmp->ConvertToGreyscale())
            {
                ImplSetSalBitmap(xImpBmp);
                SAL_INFO( "vcl.opengl", "Ref count: " << mxSalBmp.use_count() );
                return true;
            }
        }
    }

    const sal_uInt16 nBitCount = GetBitCount ();
    bool bRet = false;

    switch( eConversion )
    {
        case BmpConversion::N1BitThreshold:
        {
            BitmapEx aBmpEx(*this);
            bRet = BitmapFilter::Filter(aBmpEx, BitmapMonochromeFilter(128));
            *this = aBmpEx.GetBitmap();
        }
        break;

        case BmpConversion::N4BitGreys:
            bRet = ImplMakeGreyscales( 16 );
        break;

        case BmpConversion::N4BitColors:
        {
            if( nBitCount < 4 )
                bRet = ImplConvertUp( 4 );
            else if( nBitCount > 4 )
                bRet = ImplConvertDown( 4 );
            else
                bRet = true;
        }
        break;

        case BmpConversion::N8BitGreys:
        case BmpConversion::N8BitNoConversion:
            bRet = ImplMakeGreyscales( 256 );
        break;

        case BmpConversion::N8BitColors:
        {
            if( nBitCount < 8 )
                bRet = ImplConvertUp( 8 );
            else if( nBitCount > 8 )
                bRet = ImplConvertDown( 8 );
            else
                bRet = true;
        }
        break;

        case BmpConversion::N8BitTrans:
        {
            Color aTrans( BMP_COL_TRANS );

            if( nBitCount < 8 )
                bRet = ImplConvertUp( 8, &aTrans );
            else
                bRet = ImplConvertDown( 8, &aTrans );
        }
        break;

        case BmpConversion::N24Bit:
        {
            if( nBitCount < 24 )
                bRet = ImplConvertUp( 24 );
            else
                bRet = true;
        }
        break;

        case BmpConversion::N32Bit:
        {
            if( nBitCount < 32 )
                bRet = ImplConvertUp( 32 );
            else
                bRet = true;
        }
        break;

        default:
            OSL_FAIL( "Bitmap::Convert(): Unsupported conversion" );
        break;
    }

    return bRet;
}

bool Bitmap::ImplMakeGreyscales( sal_uInt16 nGreys )
{
    SAL_WARN_IF( nGreys != 16 && nGreys != 256, "vcl", "Only 16 or 256 greyscales are supported!" );

    ScopedReadAccess pReadAcc(*this);
    bool bRet = false;

    if( pReadAcc )
    {
        const BitmapPalette& rPal = GetGreyPalette( nGreys );
        sal_uLong nShift = ( ( nGreys == 16 ) ? 4UL : 0UL );
        bool bPalDiffers = !pReadAcc->HasPalette() || ( rPal.GetEntryCount() != pReadAcc->GetPaletteEntryCount() );

        if( !bPalDiffers )
            bPalDiffers = ( rPal != pReadAcc->GetPalette() );

        if( bPalDiffers )
        {
            Bitmap aNewBmp( GetSizePixel(), ( nGreys == 16 ) ? 4 : 8, &rPal );
            BitmapScopedWriteAccess pWriteAcc(aNewBmp);

            if( pWriteAcc )
            {
                const tools::Long nWidth = pWriteAcc->Width();
                const tools::Long nHeight = pWriteAcc->Height();

                if( pReadAcc->HasPalette() )
                {
                    for( tools::Long nY = 0; nY < nHeight; nY++ )
                    {
                        Scanline pScanline = pWriteAcc->GetScanline(nY);
                        Scanline pScanlineRead = pReadAcc->GetScanline(nY);
                        for( tools::Long nX = 0; nX < nWidth; nX++ )
                        {
                            const sal_uInt8 cIndex = pReadAcc->GetIndexFromData( pScanlineRead, nX );
                            pWriteAcc->SetPixelOnData( pScanline, nX,
                                BitmapColor(pReadAcc->GetPaletteColor( cIndex ).GetLuminance() >> nShift) );
                        }
                    }
                }
                else if( pReadAcc->GetScanlineFormat() == ScanlineFormat::N24BitTcBgr &&
                         pWriteAcc->GetScanlineFormat() == ScanlineFormat::N8BitPal )
                {
                    nShift += 8;

                    for( tools::Long nY = 0; nY < nHeight; nY++ )
                    {
                        Scanline pReadScan = pReadAcc->GetScanline( nY );
                        Scanline pWriteScan = pWriteAcc->GetScanline( nY );

                        for( tools::Long nX = 0; nX < nWidth; nX++ )
                        {
                            const sal_uLong nB = *pReadScan++;
                            const sal_uLong nG = *pReadScan++;
                            const sal_uLong nR = *pReadScan++;

                            *pWriteScan++ = static_cast<sal_uInt8>( ( nB * 28UL + nG * 151UL + nR * 77UL ) >> nShift );
                        }
                    }
                }
                else if( pReadAcc->GetScanlineFormat() == ScanlineFormat::N24BitTcRgb &&
                         pWriteAcc->GetScanlineFormat() == ScanlineFormat::N8BitPal )
                {
                    nShift += 8;

                    for( tools::Long nY = 0; nY < nHeight; nY++ )
                    {
                        Scanline pReadScan = pReadAcc->GetScanline( nY );
                        Scanline pWriteScan = pWriteAcc->GetScanline( nY );

                        for( tools::Long nX = 0; nX < nWidth; nX++ )
                        {
                            const sal_uLong nR = *pReadScan++;
                            const sal_uLong nG = *pReadScan++;
                            const sal_uLong nB = *pReadScan++;

                            *pWriteScan++ = static_cast<sal_uInt8>( ( nB * 28UL + nG * 151UL + nR * 77UL ) >> nShift );
                        }
                    }
                }
                else
                {
                    for( tools::Long nY = 0; nY < nHeight; nY++ )
                    {
                        Scanline pScanline = pWriteAcc->GetScanline(nY);
                        Scanline pScanlineRead = pReadAcc->GetScanline(nY);
                        for( tools::Long nX = 0; nX < nWidth; nX++ )
                            pWriteAcc->SetPixelOnData( pScanline, nX, BitmapColor(pReadAcc->GetPixelFromData( pScanlineRead, nX ).GetLuminance() >> nShift) );
                    }
                }

                pWriteAcc.reset();
                bRet = true;
            }

            pReadAcc.reset();

            if( bRet )
            {
                const MapMode aMap( maPrefMapMode );
                const Size aSize( maPrefSize );

                *this = aNewBmp;

                maPrefMapMode = aMap;
                maPrefSize = aSize;
            }
        }
        else
        {
            pReadAcc.reset();
            bRet = true;
        }
    }

    return bRet;
}

bool Bitmap::ImplConvertUp(sal_uInt16 nBitCount, Color const * pExtColor)
{
    SAL_WARN_IF( nBitCount <= GetBitCount(), "vcl", "New BitCount must be greater!" );

    Bitmap::ScopedReadAccess pReadAcc(*this);
    bool bRet = false;

    if (pReadAcc)
    {
        BitmapPalette aPalette;
        Bitmap aNewBmp(GetSizePixel(), nBitCount, pReadAcc->HasPalette() ? &pReadAcc->GetPalette() : &aPalette);
        BitmapScopedWriteAccess pWriteAcc(aNewBmp);

        if (pWriteAcc)
        {
            const tools::Long nWidth = pWriteAcc->Width();
            const tools::Long nHeight = pWriteAcc->Height();

            if (pWriteAcc->HasPalette())
            {
                const BitmapPalette& rOldPalette = pReadAcc->GetPalette();
                const sal_uInt16 nOldCount = rOldPalette.GetEntryCount();
                assert(nOldCount <= (1 << GetBitCount()));

                aPalette.SetEntryCount(1 << nBitCount);

                for (sal_uInt16 i = 0; i < nOldCount; i++)
                    aPalette[i] = rOldPalette[i];

                if (pExtColor)
                    aPalette[aPalette.GetEntryCount() - 1] = *pExtColor;

                pWriteAcc->SetPalette(aPalette);

                for (tools::Long nY = 0; nY < nHeight; nY++)
                {
                    Scanline pScanline = pWriteAcc->GetScanline(nY);
                    Scanline pScanlineRead = pReadAcc->GetScanline(nY);
                    for (tools::Long nX = 0; nX < nWidth; nX++)
                    {
                        pWriteAcc->SetPixelOnData(pScanline, nX, pReadAcc->GetPixelFromData(pScanlineRead, nX));
                    }
                }
            }
            else
            {
                if (pReadAcc->HasPalette())
                {
                    for (tools::Long nY = 0; nY < nHeight; nY++)
                    {
                        Scanline pScanline = pWriteAcc->GetScanline(nY);
                        Scanline pScanlineRead = pReadAcc->GetScanline(nY);
                        for (tools::Long nX = 0; nX < nWidth; nX++)
                        {
                            pWriteAcc->SetPixelOnData(pScanline, nX, pReadAcc->GetPaletteColor(pReadAcc->GetIndexFromData(pScanlineRead, nX)));
                        }
                    }
                }
                else
                {
                    for (tools::Long nY = 0; nY < nHeight; nY++)
                    {
                        Scanline pScanline = pWriteAcc->GetScanline(nY);
                        Scanline pScanlineRead = pReadAcc->GetScanline(nY);
                        for (tools::Long nX = 0; nX < nWidth; nX++)
                        {
                            pWriteAcc->SetPixelOnData(pScanline, nX, pReadAcc->GetPixelFromData(pScanlineRead, nX));
                        }
                    }
                }
            }
            bRet = true;
        }

        if (bRet)
        {
            const MapMode aMap(maPrefMapMode);
            const Size aSize(maPrefSize);

            *this = aNewBmp;

            maPrefMapMode = aMap;
            maPrefSize = aSize;
        }
    }

    return bRet;
}

bool Bitmap::ImplConvertDown(sal_uInt16 nBitCount, Color const * pExtColor)
{
    SAL_WARN_IF(nBitCount > GetBitCount(), "vcl", "New BitCount must be lower ( or equal when pExtColor is set )!");

    Bitmap::ScopedReadAccess pReadAcc(*this);
    bool bRet = false;

    if (pReadAcc)
    {
        BitmapPalette aPalette;
        Bitmap aNewBmp(GetSizePixel(), nBitCount, &aPalette);
        BitmapScopedWriteAccess pWriteAcc(aNewBmp);

        if (pWriteAcc)
        {
            const sal_uInt16 nCount = 1 << nBitCount;
            const tools::Long nWidth = pWriteAcc->Width();
            const tools::Long nWidth1 = nWidth - 1;
            const tools::Long nHeight = pWriteAcc->Height();
            Octree aOctree(*pReadAcc, pExtColor ? (nCount - 1) : nCount);
            aPalette = aOctree.GetPalette();
            InverseColorMap aColorMap(aPalette);
            BitmapColor aColor;
            ImpErrorQuad aErrQuad;
            std::vector<ImpErrorQuad> aErrQuad1(nWidth);
            std::vector<ImpErrorQuad> aErrQuad2(nWidth);
            ImpErrorQuad* pQLine1 = aErrQuad1.data();
            ImpErrorQuad* pQLine2 = nullptr;
            tools::Long nYTmp = 0;
            sal_uInt8 cIndex;
            bool bQ1 = true;

            if (pExtColor)
            {
                aPalette.SetEntryCount(aPalette.GetEntryCount() + 1);
                aPalette[aPalette.GetEntryCount() - 1] = *pExtColor;
            }

            // set Black/White always, if we have enough space
            if (aPalette.GetEntryCount() < (nCount - 1))
            {
                aPalette.SetEntryCount(aPalette.GetEntryCount() + 2);
                aPalette[aPalette.GetEntryCount() - 2] = COL_BLACK;
                aPalette[aPalette.GetEntryCount() - 1] = COL_WHITE;
            }

            pWriteAcc->SetPalette(aPalette);

            for (tools::Long nY = 0; nY < std::min(nHeight, tools::Long(2)); nY++, nYTmp++)
            {
                pQLine2 = !nY ? aErrQuad1.data() : aErrQuad2.data();
                Scanline pScanlineRead = pReadAcc->GetScanline(nYTmp);
                for (tools::Long nX = 0; nX < nWidth; nX++)
                {
                    if (pReadAcc->HasPalette())
                        pQLine2[nX] = pReadAcc->GetPaletteColor(pReadAcc->GetIndexFromData(pScanlineRead, nX));
                    else
                        pQLine2[nX] = pReadAcc->GetPixelFromData(pScanlineRead, nX);
                }
            }

            assert(pQLine2 || nHeight == 0);

            for (tools::Long nY = 0; nY < nHeight; nY++, nYTmp++)
            {
                // first pixel in the line
                cIndex = static_cast<sal_uInt8>(aColorMap.GetBestPaletteIndex(pQLine1[0].ImplGetColor()));
                Scanline pScanline = pWriteAcc->GetScanline(nY);
                pWriteAcc->SetPixelOnData(pScanline, 0, BitmapColor(cIndex));

                tools::Long nX;
                for (nX = 1; nX < nWidth1; nX++)
                {
                    aColor = pQLine1[nX].ImplGetColor();
                    cIndex = static_cast<sal_uInt8>(aColorMap.GetBestPaletteIndex(aColor));
                    aErrQuad = (ImpErrorQuad(aColor) -= pWriteAcc->GetPaletteColor(cIndex));
                    pQLine1[++nX].ImplAddColorError7(aErrQuad);
                    pQLine2[nX--].ImplAddColorError1(aErrQuad);
                    pQLine2[nX--].ImplAddColorError5(aErrQuad);
                    pQLine2[nX++].ImplAddColorError3(aErrQuad);
                    pWriteAcc->SetPixelOnData(pScanline, nX, BitmapColor(cIndex));
                }

                // Last RowPixel
                if (nX < nWidth)
                {
                    cIndex = static_cast<sal_uInt8>(aColorMap.GetBestPaletteIndex(pQLine1[nWidth1].ImplGetColor()));
                    pWriteAcc->SetPixelOnData(pScanline, nX, BitmapColor(cIndex));
                }

                // Refill/copy row buffer
                pQLine1 = pQLine2;
                bQ1 = !bQ1;
                pQLine2 = bQ1 ? aErrQuad2.data() : aErrQuad1.data();

                if (nYTmp < nHeight)
                {
                    Scanline pScanlineRead = pReadAcc->GetScanline(nYTmp);
                    for (nX = 0; nX < nWidth; nX++)
                    {
                        if (pReadAcc->HasPalette())
                            pQLine2[nX] = pReadAcc->GetPaletteColor(pReadAcc->GetIndexFromData(pScanlineRead, nX));
                        else
                            pQLine2[nX] = pReadAcc->GetPixelFromData(pScanlineRead, nX);
                    }
                }
            }

            bRet = true;
        }
        pWriteAcc.reset();

        if(bRet)
        {
            const MapMode aMap(maPrefMapMode);
            const Size aSize(maPrefSize);

            *this = aNewBmp;

            maPrefMapMode = aMap;
            maPrefSize = aSize;
        }
    }

    return bRet;
}

bool Bitmap::Scale( const double& rScaleX, const double& rScaleY, BmpScaleFlag nScaleFlag )
{
    if(basegfx::fTools::equalZero(rScaleX) || basegfx::fTools::equalZero(rScaleY))
    {
        // no scale
        return true;
    }

    if(basegfx::fTools::equal(rScaleX, 1.0) && basegfx::fTools::equal(rScaleY, 1.0))
    {
        // no scale
        return true;
    }

    const sal_uInt16 nStartCount(GetBitCount());

    if (mxSalBmp && mxSalBmp->ScalingSupported())
    {
        // implementation specific scaling
        std::shared_ptr<SalBitmap> xImpBmp(ImplGetSVData()->mpDefInst->CreateSalBitmap());
        if (xImpBmp->Create(*mxSalBmp) && xImpBmp->Scale(rScaleX, rScaleY, nScaleFlag))
        {
            ImplSetSalBitmap(xImpBmp);
            SAL_INFO( "vcl.opengl", "Ref count: " << mxSalBmp.use_count() );
            maPrefMapMode = MapMode( MapUnit::MapPixel );
            maPrefSize = xImpBmp->GetSize();
            return true;
        }
    }

    // fdo#33455
    //
    // If we start with a 1 bit image, then after scaling it in any mode except
    // BmpScaleFlag::Fast we have a 24bit image which is perfectly correct, but we
    // are going to down-shift it to mono again and Bitmap::MakeMonochrome just
    // has "Bitmap aNewBmp( GetSizePixel(), 1 );" to create a 1 bit bitmap which
    // will default to black/white and the colors mapped to which ever is closer
    // to black/white
    //
    // So the easiest thing to do to retain the colors of 1 bit bitmaps is to
    // just use the fast scale rather than attempting to count unique colors in
    // the other converters and pass all the info down through
    // Bitmap::MakeMonochrome
    if (nStartCount == 1)
        nScaleFlag = BmpScaleFlag::Fast;

    BitmapEx aBmpEx(*this);
    bool bRetval(false);

    switch(nScaleFlag)
    {
        case BmpScaleFlag::Default:
            if (GetSizePixel().Width() < 2 || GetSizePixel().Height() < 2)
                bRetval = BitmapFilter::Filter(aBmpEx, BitmapFastScaleFilter(rScaleX, rScaleY));
            else
                bRetval = BitmapFilter::Filter(aBmpEx, BitmapScaleSuperFilter(rScaleX, rScaleY));
            break;

        case BmpScaleFlag::Fast:
        case BmpScaleFlag::NearestNeighbor:
            bRetval = BitmapFilter::Filter(aBmpEx, BitmapFastScaleFilter(rScaleX, rScaleY));
            break;

        case BmpScaleFlag::Interpolate:
            bRetval = BitmapFilter::Filter(aBmpEx, BitmapInterpolateScaleFilter(rScaleX, rScaleY));
            break;

        case BmpScaleFlag::Super:
            bRetval = BitmapFilter::Filter(aBmpEx, BitmapScaleSuperFilter(rScaleX, rScaleY));
            break;
        case BmpScaleFlag::BestQuality:
        case BmpScaleFlag::Lanczos:
            bRetval = BitmapFilter::Filter(aBmpEx, vcl::BitmapScaleLanczos3Filter(rScaleX, rScaleY));
            break;

        case BmpScaleFlag::BiCubic:
            bRetval = BitmapFilter::Filter(aBmpEx, vcl::BitmapScaleBicubicFilter(rScaleX, rScaleY));
            break;

        case BmpScaleFlag::BiLinear:
            bRetval = BitmapFilter::Filter(aBmpEx, vcl::BitmapScaleBilinearFilter(rScaleX, rScaleY));
            break;
    }

    if (bRetval)
        *this = aBmpEx.GetBitmap();

    OSL_ENSURE(!bRetval || nStartCount == GetBitCount(), "Bitmap::Scale has changed the ColorDepth, this should *not* happen (!)");
    return bRetval;
}

bool Bitmap::Scale( const Size& rNewSize, BmpScaleFlag nScaleFlag )
{
    const Size aSize( GetSizePixel() );
    bool bRet;

    if( aSize.Width() && aSize.Height() )
    {
        bRet = Scale( static_cast<double>(rNewSize.Width()) / aSize.Width(),
                      static_cast<double>(rNewSize.Height()) / aSize.Height(),
                      nScaleFlag );
    }
    else
        bRet = true;

    return bRet;
}

bool Bitmap::HasFastScale()
{
#if HAVE_FEATURE_SKIA
    if( SkiaHelper::isVCLSkiaEnabled() && SkiaHelper::renderMethodToUse() != SkiaHelper::RenderRaster)
        return true;
#endif
    return false;
}

void Bitmap::AdaptBitCount(Bitmap& rNew) const
{
    // aNew is the result of some operation; adapt it's BitCount to the original (this)
    if(GetBitCount() == rNew.GetBitCount())
        return;

    switch(GetBitCount())
    {
        case 1:
        {
            rNew.Convert(BmpConversion::N1BitThreshold);
            break;
        }
        case 4:
        {
            if(HasGreyPaletteAny())
            {
                rNew.Convert(BmpConversion::N4BitGreys);
            }
            else
            {
                rNew.Convert(BmpConversion::N4BitColors);
            }
            break;
        }
        case 8:
        {
            if(HasGreyPaletteAny())
            {
                rNew.Convert(BmpConversion::N8BitGreys);
            }
            else
            {
                rNew.Convert(BmpConversion::N8BitColors);
            }
            break;
        }
        case 24:
        {
            rNew.Convert(BmpConversion::N24Bit);
            break;
        }
        case 32:
        {
            rNew.Convert(BmpConversion::N32Bit);
            break;
        }
        default:
        {
            SAL_WARN("vcl", "BitDepth adaptation failed, from " << rNew.GetBitCount() << " to " << GetBitCount());
            break;
        }
    }
}

static tools::Long* shiftColor(tools::Long* pColorArray, BitmapColor const& rColor)
{
    *pColorArray++ = static_cast<tools::Long>(rColor.GetBlue()) << 12;
    *pColorArray++ = static_cast<tools::Long>(rColor.GetGreen()) << 12;
    *pColorArray++ = static_cast<tools::Long>(rColor.GetRed()) << 12;
    return pColorArray;
}
static BitmapColor getColor(BitmapReadAccess *pReadAcc, tools::Long nZ)
{
    Scanline pScanlineRead = pReadAcc->GetScanline(0);
    if (pReadAcc->HasPalette())
        return pReadAcc->GetPaletteColor(pReadAcc->GetIndexFromData(pScanlineRead, nZ));
    else
        return pReadAcc->GetPixelFromData(pScanlineRead, nZ);
}

bool Bitmap::Dither()
{
    const Size aSize( GetSizePixel() );
    if( aSize.Width() == 1 || aSize.Height() == 1 )
        return true;
    if( ( aSize.Width() > 3 ) && ( aSize.Height() > 2 ) )
    {
        ScopedReadAccess pReadAcc(*this);
        Bitmap aNewBmp( GetSizePixel(), 8 );
        BitmapScopedWriteAccess pWriteAcc(aNewBmp);
        if( pReadAcc && pWriteAcc )
        {
            BitmapColor aColor;
            tools::Long nWidth = pReadAcc->Width();
            tools::Long nWidth1 = nWidth - 1;
            tools::Long nHeight = pReadAcc->Height();
            tools::Long nW = nWidth * 3;
            tools::Long nW2 = nW - 3;
            std::unique_ptr<tools::Long[]> p1(new tools::Long[ nW ]);
            std::unique_ptr<tools::Long[]> p2(new tools::Long[ nW ]);
            tools::Long* p1T = p1.get();
            tools::Long* p2T = p2.get();
            tools::Long* pTmp;
            pTmp = p2T;
            for (tools::Long nZ = 0; nZ < nWidth; nZ++)
            {
                pTmp = shiftColor(pTmp, getColor(pReadAcc.get(), nZ));
            }
            tools::Long nRErr, nGErr, nBErr;
            tools::Long nRC, nGC, nBC;
            for( tools::Long nY = 1, nYAcc = 0; nY <= nHeight; nY++, nYAcc++ )
            {
                pTmp = p1T;
                p1T = p2T;
                p2T = pTmp;
                if (nY < nHeight)
                {
                    for (tools::Long nZ = 0; nZ < nWidth; nZ++)
                    {
                        pTmp = shiftColor(pTmp, getColor(pReadAcc.get(), nZ));
                    }
                }
                // Examine first Pixel separately
                tools::Long nX = 0;
                tools::Long nTemp;
                CALC_ERRORS;
                CALC_TABLES7;
                nX -= 5;
                CALC_TABLES5;
                Scanline pScanline = pWriteAcc->GetScanline(nYAcc);
                pWriteAcc->SetPixelOnData( pScanline, 0, BitmapColor(static_cast<sal_uInt8>(nVCLBLut[ nBC ] + nVCLGLut[nGC ] + nVCLRLut[nRC ])) );
                // Get middle Pixels using a loop
                tools::Long nXAcc;
                for ( nX = 3, nXAcc = 1; nX < nW2; nXAcc++ )
                {
                    CALC_ERRORS;
                    CALC_TABLES7;
                    nX -= 8;
                    CALC_TABLES3;
                    CALC_TABLES5;
                    pWriteAcc->SetPixelOnData( pScanline, nXAcc, BitmapColor(static_cast<sal_uInt8>(nVCLBLut[ nBC ] + nVCLGLut[nGC ] + nVCLRLut[nRC ])) );
                }
                // Treat last Pixel separately
                CALC_ERRORS;
                nX -= 5;
                CALC_TABLES3;
                CALC_TABLES5;
                pWriteAcc->SetPixelOnData( pScanline, nWidth1, BitmapColor(static_cast<sal_uInt8>(nVCLBLut[ nBC ] + nVCLGLut[nGC ] + nVCLRLut[nRC ])) );
            }
            pReadAcc.reset();
            pWriteAcc.reset();
            const MapMode aMap( maPrefMapMode );
            const Size aPrefSize( maPrefSize );
            *this = aNewBmp;
            maPrefMapMode = aMap;
            maPrefSize = aPrefSize;
            return true;
        }
        pReadAcc.reset();
        pWriteAcc.reset();
    }
    return false;
}

void Bitmap::Vectorize( GDIMetaFile& rMtf, sal_uInt8 cReduce, const Link<tools::Long,void>* pProgress )
{
    ImplVectorizer::ImplVectorize( *this, rMtf, cReduce, pProgress );
}

bool Bitmap::Adjust( short nLuminancePercent, short nContrastPercent,
                     short nChannelRPercent, short nChannelGPercent, short nChannelBPercent,
                     double fGamma, bool bInvert, bool msoBrightness )
{
    bool bRet = false;

    // nothing to do => return quickly
    if( !nLuminancePercent && !nContrastPercent &&
        !nChannelRPercent && !nChannelGPercent && !nChannelBPercent &&
        ( fGamma == 1.0 ) && !bInvert )
    {
        bRet = true;
    }
    else
    {
        BitmapScopedWriteAccess pAcc(*this);

        if( pAcc )
        {
            BitmapColor aCol;
            const tools::Long nW = pAcc->Width();
            const tools::Long nH = pAcc->Height();
            std::unique_ptr<sal_uInt8[]> cMapR(new sal_uInt8[ 256 ]);
            std::unique_ptr<sal_uInt8[]> cMapG(new sal_uInt8[ 256 ]);
            std::unique_ptr<sal_uInt8[]> cMapB(new sal_uInt8[ 256 ]);
            double fM, fROff, fGOff, fBOff, fOff;

            // calculate slope
            if( nContrastPercent >= 0 )
                fM = 128.0 / ( 128.0 - 1.27 * MinMax( nContrastPercent, 0, 100 ) );
            else
                fM = ( 128.0 + 1.27 * MinMax( nContrastPercent, -100, 0 ) ) / 128.0;

            if(!msoBrightness)
                // total offset = luminance offset + contrast offset
                fOff = MinMax( nLuminancePercent, -100, 100 ) * 2.55 + 128.0 - fM * 128.0;
            else
                fOff = MinMax( nLuminancePercent, -100, 100 ) * 2.55;

            // channel offset = channel offset + total offset
            fROff = nChannelRPercent * 2.55 + fOff;
            fGOff = nChannelGPercent * 2.55 + fOff;
            fBOff = nChannelBPercent * 2.55 + fOff;

            // calculate gamma value
            fGamma = ( fGamma <= 0.0 || fGamma > 10.0 ) ? 1.0 : ( 1.0 / fGamma );
            const bool bGamma = ( fGamma != 1.0 );

            // create mapping table
            for( tools::Long nX = 0; nX < 256; nX++ )
            {
                if(!msoBrightness)
                {
                    cMapR[ nX ] = static_cast<sal_uInt8>(MinMax( FRound( nX * fM + fROff ), 0, 255 ));
                    cMapG[ nX ] = static_cast<sal_uInt8>(MinMax( FRound( nX * fM + fGOff ), 0, 255 ));
                    cMapB[ nX ] = static_cast<sal_uInt8>(MinMax( FRound( nX * fM + fBOff ), 0, 255 ));
                }
                else
                {
                    // LO simply uses (in a somewhat optimized form) "newcolor = (oldcolor-128)*contrast+brightness+128"
                    // as the formula, i.e. contrast first, brightness afterwards. MSOffice, for whatever weird reason,
                    // use neither first, but apparently it applies half of brightness before contrast and half afterwards.
                    cMapR[ nX ] = static_cast<sal_uInt8>(MinMax( FRound( (nX+fROff/2-128) * fM + 128 + fROff/2 ), 0, 255 ));
                    cMapG[ nX ] = static_cast<sal_uInt8>(MinMax( FRound( (nX+fGOff/2-128) * fM + 128 + fGOff/2 ), 0, 255 ));
                    cMapB[ nX ] = static_cast<sal_uInt8>(MinMax( FRound( (nX+fBOff/2-128) * fM + 128 + fBOff/2 ), 0, 255 ));
                }
                if( bGamma )
                {
                    cMapR[ nX ] = GAMMA( cMapR[ nX ], fGamma );
                    cMapG[ nX ] = GAMMA( cMapG[ nX ], fGamma );
                    cMapB[ nX ] = GAMMA( cMapB[ nX ], fGamma );
                }

                if( bInvert )
                {
                    cMapR[ nX ] = ~cMapR[ nX ];
                    cMapG[ nX ] = ~cMapG[ nX ];
                    cMapB[ nX ] = ~cMapB[ nX ];
                }
            }

            // do modifying
            if( pAcc->HasPalette() )
            {
                BitmapColor aNewCol;

                for( sal_uInt16 i = 0, nCount = pAcc->GetPaletteEntryCount(); i < nCount; i++ )
                {
                    const BitmapColor& rCol = pAcc->GetPaletteColor( i );
                    aNewCol.SetRed( cMapR[ rCol.GetRed() ] );
                    aNewCol.SetGreen( cMapG[ rCol.GetGreen() ] );
                    aNewCol.SetBlue( cMapB[ rCol.GetBlue() ] );
                    pAcc->SetPaletteColor( i, aNewCol );
                }
            }
            else if( pAcc->GetScanlineFormat() == ScanlineFormat::N24BitTcBgr )
            {
                for( tools::Long nY = 0; nY < nH; nY++ )
                {
                    Scanline pScan = pAcc->GetScanline( nY );

                    for( tools::Long nX = 0; nX < nW; nX++ )
                    {
                        *pScan = cMapB[ *pScan ]; pScan++;
                        *pScan = cMapG[ *pScan ]; pScan++;
                        *pScan = cMapR[ *pScan ]; pScan++;
                    }
                }
            }
            else if( pAcc->GetScanlineFormat() == ScanlineFormat::N24BitTcRgb )
            {
                for( tools::Long nY = 0; nY < nH; nY++ )
                {
                    Scanline pScan = pAcc->GetScanline( nY );

                    for( tools::Long nX = 0; nX < nW; nX++ )
                    {
                        *pScan = cMapR[ *pScan ]; pScan++;
                        *pScan = cMapG[ *pScan ]; pScan++;
                        *pScan = cMapB[ *pScan ]; pScan++;
                    }
                }
            }
            else
            {
                for( tools::Long nY = 0; nY < nH; nY++ )
                {
                    Scanline pScanline = pAcc->GetScanline(nY);
                    for( tools::Long nX = 0; nX < nW; nX++ )
                    {
                        aCol = pAcc->GetPixelFromData( pScanline, nX );
                        aCol.SetRed( cMapR[ aCol.GetRed() ] );
                        aCol.SetGreen( cMapG[ aCol.GetGreen() ] );
                        aCol.SetBlue( cMapB[ aCol.GetBlue() ] );
                        pAcc->SetPixelOnData( pScanline, nX, aCol );
                    }
                }
            }

            pAcc.reset();
            bRet = true;
        }
    }

    return bRet;
}

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */