vcl/source/bitmap/BitmapFastScaleFilter.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/helpers.hxx>
  21
  22 #include <vcl/bitmapex.hxx>
  23 #include <vcl/bitmapaccess.hxx>
  24
  25 #include <bitmapwriteaccess.hxx>
  26 #include <BitmapFastScaleFilter.hxx>
  27 #include <sal/log.hxx>
  28
  29 BitmapEx BitmapFastScaleFilter::execute(BitmapEx const& rBitmapEx) const
  30 {
  31     SAL_INFO("vcl.gdi", "BitmapFastScaleFilter::execute()");
  32
  33     Bitmap aBitmap(rBitmapEx.GetBitmap());
  34
  35     const Size aSizePix(aBitmap.GetSizePixel());
  36     const tools::Long nNewWidth = FRound(aSizePix.Width() * mfScaleX);
  37     const tools::Long nNewHeight = FRound(aSizePix.Height() * mfScaleY);
  38     bool bRet = false;
  39
  40     SAL_INFO("vcl.gdi", "New width: " << nNewWidth << "\nNew height: " << nNewHeight);
  41
  42     if (nNewWidth && nNewHeight)
  43     {
  44         Bitmap::ScopedReadAccess pReadAcc(aBitmap);
  45
  46         if (pReadAcc)
  47         {
  48             Bitmap aNewBmp(Size(nNewWidth, nNewHeight), aBitmap.GetBitCount(),
  49                            &pReadAcc->GetPalette());
  50             BitmapScopedWriteAccess pWriteAcc(aNewBmp);
  51
  52             if (pWriteAcc)
  53             {
  54                 const tools::Long nScanlineSize = pWriteAcc->GetScanlineSize();
  55                 const tools::Long nNewHeight1 = nNewHeight - 1;
  56
  57                 if (nNewWidth && nNewHeight)
  58                 {
  59                     const double nWidth = pReadAcc->Width();
  60                     const double nHeight = pReadAcc->Height();
  61                     std::unique_ptr<tools::Long[]> pLutX(new tools::Long[nNewWidth]);
  62                     std::unique_ptr<tools::Long[]> pLutY(new tools::Long[nNewHeight]);
  63
  64                     for (tools::Long nX = 0; nX < nNewWidth; nX++)
  65                     {
  66                         pLutX[nX] = tools::Long(nX * nWidth / nNewWidth);
  67                     }
  68
  69                     for (tools::Long nY = 0; nY < nNewHeight; nY++)
  70                     {
  71                         pLutY[nY] = tools::Long(nY * nHeight / nNewHeight);
  72                     }
  73
  74                     tools::Long nActY = 0;
  75                     while (nActY < nNewHeight)
  76                     {
  77                         tools::Long nMapY = pLutY[nActY];
  78                         Scanline pScanline = pWriteAcc->GetScanline(nActY);
  79                         Scanline pScanlineRead = pReadAcc->GetScanline(nMapY);
  80
  81                         for (tools::Long nX = 0; nX < nNewWidth; nX++)
  82                         {
  83                             pWriteAcc->SetPixelOnData(
  84                                 pScanline, nX,
  85                                 pReadAcc->GetPixelFromData(pScanlineRead, pLutX[nX]));
  86                         }
  87
  88                         while ((nActY < nNewHeight1) && (pLutY[nActY + 1] == nMapY))
  89                         {
  90                             memcpy(pWriteAcc->GetScanline(nActY + 1), pWriteAcc->GetScanline(nActY),
  91                                    nScanlineSize);
  92                             nActY++;
  93                         }
  94                         nActY++;
  95                     }
  96
  97                     bRet = true;
  98                 }
  99
 100                 pWriteAcc.reset();
 101             }
 102             pReadAcc.reset();
 103
 104             if (bRet)
 105             {
 106                 aBitmap.ReassignWithSize(aNewBmp);
 107                 SAL_INFO("vcl.gdi", "Bitmap size: " << aBitmap.GetSizePixel());
 108             }
 109             else
 110             {
 111                 SAL_WARN("vcl.gdi", "no resize");
 112             }
 113         }
 114     }
 115
 116     Bitmap aMask(rBitmapEx.GetMask());
 117
 118     if (bRet && (rBitmapEx.GetTransparentType() == TransparentType::Bitmap) && !aMask.IsEmpty())
 119         bRet = aMask.Scale(maSize, BmpScaleFlag::Fast);
 120
 121     SAL_WARN_IF(!aMask.IsEmpty() && aBitmap.GetSizePixel() != aMask.GetSizePixel(), "vcl",
 122                 "BitmapEx::Scale(): size mismatch for bitmap and alpha mask.");
 123
 124     if (bRet)
 125         return BitmapEx(aBitmap, aMask);
 126
 127     return BitmapEx();
 128 }
 129
 130 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */