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.
   4  *
   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 <tools/debug.hxx>
  21 #include <vcl/bmpacc.hxx>
  22 #include <tools/color.hxx>
  23 #include <vcl/alpha.hxx>
  24
  25 AlphaMask::AlphaMask()
  26 {
  27 }
  28
  29 AlphaMask::AlphaMask( const Bitmap& rBitmap ) :
  30     Bitmap( rBitmap )
  31 {
  32     if( !!rBitmap )
  33         Bitmap::Convert( BMP_CONVERSION_8BIT_GREYS );
  34 }
  35
  36 AlphaMask::AlphaMask( const AlphaMask& rAlphaMask ) :
  37     Bitmap( rAlphaMask )
  38 {
  39 }
  40
  41 AlphaMask::AlphaMask( const Size& rSizePixel, sal_uInt8* pEraseTransparency ) :
  42     Bitmap( rSizePixel, 8, &Bitmap::GetGreyPalette( 256 ) )
  43 {
  44     if( pEraseTransparency )
  45         Bitmap::Erase( Color( *pEraseTransparency, *pEraseTransparency, *pEraseTransparency ) );
  46 }
  47
  48 AlphaMask::~AlphaMask()
  49 {
  50 }
  51
  52 AlphaMask& AlphaMask::operator=( const Bitmap& rBitmap )
  53 {
  54     *(Bitmap*) this = rBitmap;
  55
  56     if( !!rBitmap )
  57         Bitmap::Convert( BMP_CONVERSION_8BIT_GREYS );
  58
  59     return *this;
  60 }
  61
  62 const Bitmap& AlphaMask::ImplGetBitmap() const
  63 {
  64     return( (const Bitmap&) *this );
  65 }
  66
  67 void AlphaMask::ImplSetBitmap( const Bitmap& rBitmap )
  68 {
  69     SAL_WARN_IF( 8 != rBitmap.GetBitCount(), "vcl.gdi", "Bitmap should be 8bpp, not " << rBitmap.GetBitCount() << "bpp" );
  70     SAL_WARN_IF( !rBitmap.HasGreyPalette(), "vcl.gdi", "Bitmap isn't greyscale" );
  71     *(Bitmap*) this = rBitmap;
  72 }
  73
  74 Bitmap AlphaMask::GetBitmap() const
  75 {
  76     return ImplGetBitmap();
  77 }
  78
  79 bool AlphaMask::Erase( sal_uInt8 cTransparency )
  80 {
  81     return Bitmap::Erase( Color( cTransparency, cTransparency, cTransparency ) );
  82 }
  83
  84 bool AlphaMask::Replace( const Bitmap& rMask, sal_uInt8 cReplaceTransparency )
  85 {
  86     BitmapReadAccess*   pMaskAcc = ( (Bitmap&) rMask ).AcquireReadAccess();
  87     BitmapWriteAccess*  pAcc = AcquireWriteAccess();
  88     bool                bRet = false;
  89
  90     if( pMaskAcc && pAcc )
  91     {
  92         const BitmapColor   aReplace( cReplaceTransparency );
  93         const long          nWidth = std::min( pMaskAcc->Width(), pAcc->Width() );
  94         const long          nHeight = std::min( pMaskAcc->Height(), pAcc->Height() );
  95         const BitmapColor   aMaskWhite( pMaskAcc->GetBestMatchingColor( Color( COL_WHITE ) ) );
  96
  97         for( long nY = 0L; nY < nHeight; nY++ )
  98             for( long nX = 0L; nX < nWidth; nX++ )
  99                 if( pMaskAcc->GetPixel( nY, nX ) == aMaskWhite )
 100                     pAcc->SetPixel( nY, nX, aReplace );
 101     }
 102
 103     Bitmap::ReleaseAccess( pMaskAcc );
 104     ReleaseAccess( pAcc );
 105
 106     return bRet;
 107 }
 108
 109 bool AlphaMask::Replace( sal_uInt8 cSearchTransparency, sal_uInt8 cReplaceTransparency, sal_uLong
 110 #ifdef DBG_UTIL
 111 nTol
 112 #endif
 113 )
 114 {
 115     BitmapWriteAccess*  pAcc = AcquireWriteAccess();
 116     bool                bRet = false;
 117
 118     DBG_ASSERT( !nTol, "AlphaMask::Replace: nTol not used yet" );
 119
 120     if( pAcc && pAcc->GetBitCount() == 8 )
 121     {
 122         const long nWidth = pAcc->Width(), nHeight = pAcc->Height();
 123
 124         if( pAcc->GetScanlineFormat() == BMP_FORMAT_8BIT_PAL )
 125         {
 126             for( long nY = 0L; nY < nHeight; nY++ )
 127             {
 128                 Scanline pScan = pAcc->GetScanline( nY );
 129
 130                 for( long nX = 0L; nX < nWidth; nX++, pScan++ )
 131                 {
 132                     if( *pScan == cSearchTransparency )
 133                         *pScan = cReplaceTransparency;
 134                 }
 135             }
 136         }
 137         else
 138         {
 139             BitmapColor aReplace( cReplaceTransparency );
 140
 141             for( long nY = 0L; nY < nHeight; nY++ )
 142             {
 143                 for( long nX = 0L; nX < nWidth; nX++ )
 144                 {
 145                     if( pAcc->GetPixel( nY, nX ).GetIndex() == cSearchTransparency )
 146                         pAcc->SetPixel( nY, nX, aReplace );
 147                 }
 148             }
 149         }
 150
 151         bRet = true;
 152     }
 153
 154     if( pAcc )
 155         ReleaseAccess( pAcc );
 156
 157     return bRet;
 158 }
 159
 160 void AlphaMask::ReleaseAccess( BitmapReadAccess* pAccess )
 161 {
 162     if( pAccess )
 163     {
 164         Bitmap::ReleaseAccess( pAccess );
 165         Bitmap::Convert( BMP_CONVERSION_8BIT_GREYS );
 166     }
 167 }
 168
 169 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */