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Diffstat (limited to 'vcl/source/gdi/alpha.cxx')
| -rw-r--r-- | vcl/source/gdi/alpha.cxx | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/vcl/source/gdi/alpha.cxx b/vcl/source/gdi/alpha.cxx new file mode 100644 index 000000000..3fa43c8ea --- /dev/null +++ b/vcl/source/gdi/alpha.cxx @@ -0,0 +1,176 @@ +/* -*- 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 <vcl/bitmapaccess.hxx> +#include <tools/color.hxx> +#include <vcl/alpha.hxx> +#include <bitmapwriteaccess.hxx> +#include <sal/log.hxx> + +AlphaMask::AlphaMask() = default; + +AlphaMask::AlphaMask( const Bitmap& rBitmap ) : + Bitmap( rBitmap ) +{ + if( !!rBitmap ) + Convert( BmpConversion::N8BitNoConversion ); +} + +AlphaMask::AlphaMask( const AlphaMask& ) = default; + +AlphaMask::AlphaMask( AlphaMask&& ) = default; + +AlphaMask::AlphaMask( const Size& rSizePixel, const sal_uInt8* pEraseTransparency ) : + Bitmap( rSizePixel, 8, &Bitmap::GetGreyPalette( 256 ) ) +{ + if( pEraseTransparency ) + Bitmap::Erase( Color( *pEraseTransparency, *pEraseTransparency, *pEraseTransparency ) ); +} + +AlphaMask::~AlphaMask() = default; + +AlphaMask& AlphaMask::operator=( const Bitmap& rBitmap ) +{ + *static_cast<Bitmap*>(this) = rBitmap; + + if( !!rBitmap ) + Convert( BmpConversion::N8BitNoConversion ); + + return *this; +} + +const Bitmap& AlphaMask::ImplGetBitmap() const +{ + return *this; +} + +void AlphaMask::ImplSetBitmap( const Bitmap& rBitmap ) +{ + SAL_WARN_IF( 8 != rBitmap.GetBitCount(), "vcl.gdi", "Bitmap should be 8bpp, not " << rBitmap.GetBitCount() << "bpp" ); + SAL_WARN_IF( !rBitmap.HasGreyPalette8Bit(), "vcl.gdi", "Bitmap isn't greyscale" ); + *static_cast<Bitmap*>(this) = rBitmap; +} + +Bitmap const & AlphaMask::GetBitmap() const +{ + return ImplGetBitmap(); +} + +void AlphaMask::Erase( sal_uInt8 cTransparency ) +{ + Bitmap::Erase( Color( cTransparency, cTransparency, cTransparency ) ); +} + +void AlphaMask::Replace( const Bitmap& rMask, sal_uInt8 cReplaceTransparency ) +{ + Bitmap::ScopedReadAccess pMaskAcc( const_cast<Bitmap&>(rMask) ); + AlphaScopedWriteAccess pAcc(*this); + + if( pMaskAcc && pAcc ) + { + const BitmapColor aReplace( cReplaceTransparency ); + const long nWidth = std::min( pMaskAcc->Width(), pAcc->Width() ); + const long nHeight = std::min( pMaskAcc->Height(), pAcc->Height() ); + const BitmapColor aMaskWhite( pMaskAcc->GetBestMatchingColor( COL_WHITE ) ); + + for( long nY = 0; nY < nHeight; nY++ ) + { + Scanline pScanline = pAcc->GetScanline(nY); + Scanline pScanlineMask = pMaskAcc->GetScanline(nY); + for( long nX = 0; nX < nWidth; nX++ ) + if( pMaskAcc->GetPixelFromData( pScanlineMask, nX ) == aMaskWhite ) + pAcc->SetPixelOnData( pScanline, nX, aReplace ); + } + } +} + +void AlphaMask::Replace( sal_uInt8 cSearchTransparency, sal_uInt8 cReplaceTransparency ) +{ + AlphaScopedWriteAccess pAcc(*this); + + if( pAcc && pAcc->GetBitCount() == 8 ) + { + const long nWidth = pAcc->Width(), nHeight = pAcc->Height(); + + if( pAcc->GetScanlineFormat() == ScanlineFormat::N8BitPal ) + { + for( long nY = 0; nY < nHeight; nY++ ) + { + Scanline pScan = pAcc->GetScanline( nY ); + + for( long nX = 0; nX < nWidth; nX++, pScan++ ) + { + if( *pScan == cSearchTransparency ) + *pScan = cReplaceTransparency; + } + } + } + else + { + BitmapColor aReplace( cReplaceTransparency ); + + for( long nY = 0; nY < nHeight; nY++ ) + { + Scanline pScanline = pAcc->GetScanline(nY); + for( long nX = 0; nX < nWidth; nX++ ) + { + if( pAcc->GetIndexFromData( pScanline, nX ) == cSearchTransparency ) + pAcc->SetPixelOnData( pScanline, nX, aReplace ); + } + } + } + } +} + +void AlphaMask::BlendWith(const Bitmap& rOther) +{ + AlphaMask aOther(rOther); // to 8 bits + Bitmap::ScopedReadAccess pOtherAcc(aOther); + AlphaScopedWriteAccess pAcc(*this); + if (pOtherAcc && pAcc && pOtherAcc->GetBitCount() == 8 && pAcc->GetBitCount() == 8) + { + const long nHeight = std::min(pOtherAcc->Height(), pAcc->Height()); + const long nWidth = std::min(pOtherAcc->Width(), pAcc->Width()); + for (long y = 0; y < nHeight; ++y) + { + Scanline scanline = pAcc->GetScanline( y ); + ConstScanline otherScanline = pOtherAcc->GetScanline( y ); + for (long x = 0; x < nWidth; ++x) + { + // Use sal_uInt16 for following multiplication + const sal_uInt16 nGrey1 = *scanline; + const sal_uInt16 nGrey2 = *otherScanline; + *scanline = static_cast<sal_uInt8>(nGrey1 + nGrey2 - nGrey1 * nGrey2 / 255); + ++scanline; + ++otherScanline; + } + } + } +} + +void AlphaMask::ReleaseAccess( BitmapReadAccess* pAccess ) +{ + if( pAccess ) + { + Bitmap::ReleaseAccess( pAccess ); + Convert( BmpConversion::N8BitNoConversion ); + } +} + +/* vim:set shiftwidth=4 softtabstop=4 expandtab: */ |