vcl/source/gdi/alpha.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
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   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <vcl/bitmapaccess.hxx>
  21 #include <tools/color.hxx>
  22 #include <vcl/alpha.hxx>
  23 #include <bitmapwriteaccess.hxx>
  24 #include <sal/log.hxx>
  25
  26 AlphaMask::AlphaMask() = default;
  27
  28 AlphaMask::AlphaMask( const Bitmap& rBitmap ) :
  29     Bitmap( rBitmap )
  30 {
  31     if( !!rBitmap )
  32         Convert( BmpConversion::N8BitGreys );
  33 }
  34
  35 AlphaMask::AlphaMask( const AlphaMask& ) = default;
  36
  37 AlphaMask::AlphaMask( AlphaMask&& ) = default;
  38
  39 AlphaMask::AlphaMask( const Size& rSizePixel, const sal_uInt8* pEraseTransparency ) :
  40     Bitmap( rSizePixel, 8, &Bitmap::GetGreyPalette( 256 ) )
  41 {
  42     if( pEraseTransparency )
  43         Bitmap::Erase( Color( *pEraseTransparency, *pEraseTransparency, *pEraseTransparency ) );
  44 }
  45
  46 AlphaMask::~AlphaMask() = default;
  47
  48 AlphaMask& AlphaMask::operator=( const Bitmap& rBitmap )
  49 {
  50     *static_cast<Bitmap*>(this) = rBitmap;
  51
  52     if( !!rBitmap )
  53         Convert( BmpConversion::N8BitGreys );
  54
  55     return *this;
  56 }
  57
  58 const Bitmap& AlphaMask::ImplGetBitmap() const
  59 {
  60     return *this;
  61 }
  62
  63 void AlphaMask::ImplSetBitmap( const Bitmap& rBitmap )
  64 {
  65     SAL_WARN_IF( 8 != rBitmap.GetBitCount(), "vcl.gdi", "Bitmap should be 8bpp, not " << rBitmap.GetBitCount() << "bpp" );
  66     SAL_WARN_IF( !rBitmap.HasGreyPalette(), "vcl.gdi", "Bitmap isn't greyscale" );
  67     *static_cast<Bitmap*>(this) = rBitmap;
  68 }
  69
  70 Bitmap const & AlphaMask::GetBitmap() const
  71 {
  72     return ImplGetBitmap();
  73 }
  74
  75 void AlphaMask::Erase( sal_uInt8 cTransparency )
  76 {
  77     Bitmap::Erase( Color( cTransparency, cTransparency, cTransparency ) );
  78 }
  79
  80 void AlphaMask::Replace( const Bitmap& rMask, sal_uInt8 cReplaceTransparency )
  81 {
  82     Bitmap::ScopedReadAccess pMaskAcc( const_cast<Bitmap&>(rMask) );
  83     AlphaScopedWriteAccess pAcc(*this);
  84
  85     if( pMaskAcc && pAcc )
  86     {
  87         const BitmapColor   aReplace( cReplaceTransparency );
  88         const long          nWidth = std::min( pMaskAcc->Width(), pAcc->Width() );
  89         const long          nHeight = std::min( pMaskAcc->Height(), pAcc->Height() );
  90         const BitmapColor   aMaskWhite( pMaskAcc->GetBestMatchingColor( COL_WHITE ) );
  91
  92         for( long nY = 0; nY < nHeight; nY++ )
  93         {
  94             Scanline pScanline = pAcc->GetScanline(nY);
  95             Scanline pScanlineMask = pMaskAcc->GetScanline(nY);
  96             for( long nX = 0; nX < nWidth; nX++ )
  97                 if( pMaskAcc->GetPixelFromData( pScanlineMask, nX ) == aMaskWhite )
  98                     pAcc->SetPixelOnData( pScanline, nX, aReplace );
  99         }
 100     }
 101 }
 102
 103 void AlphaMask::Replace( sal_uInt8 cSearchTransparency, sal_uInt8 cReplaceTransparency )
 104 {
 105     AlphaScopedWriteAccess pAcc(*this);
 106
 107     if( pAcc && pAcc->GetBitCount() == 8 )
 108     {
 109         const long nWidth = pAcc->Width(), nHeight = pAcc->Height();
 110
 111         if( pAcc->GetScanlineFormat() == ScanlineFormat::N8BitPal )
 112         {
 113             for( long nY = 0; nY < nHeight; nY++ )
 114             {
 115                 Scanline pScan = pAcc->GetScanline( nY );
 116
 117                 for( long nX = 0; nX < nWidth; nX++, pScan++ )
 118                 {
 119                     if( *pScan == cSearchTransparency )
 120                         *pScan = cReplaceTransparency;
 121                 }
 122             }
 123         }
 124         else
 125         {
 126             BitmapColor aReplace( cReplaceTransparency );
 127
 128             for( long nY = 0; nY < nHeight; nY++ )
 129             {
 130                 Scanline pScanline = pAcc->GetScanline(nY);
 131                 for( long nX = 0; nX < nWidth; nX++ )
 132                 {
 133                     if( pAcc->GetIndexFromData( pScanline, nX ) == cSearchTransparency )
 134                         pAcc->SetPixelOnData( pScanline, nX, aReplace );
 135                 }
 136             }
 137         }
 138     }
 139 }
 140
 141 void AlphaMask::ReleaseAccess( BitmapReadAccess* pAccess )
 142 {
 143     if( pAccess )
 144     {
 145         Bitmap::ReleaseAccess( pAccess );
 146         Convert( BmpConversion::N8BitGreys );
 147     }
 148 }
 149
 150 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */