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 <sal/log.hxx>
  21 #include <tools/helpers.hxx>
  22
  23 #include <vcl/bitmapex.hxx>
  24 #include <vcl/BitmapWriteAccess.hxx>
  25
  26 #include <bitmap/BitmapFastScaleFilter.hxx>
  27
  28 BitmapEx BitmapFastScaleFilter::execute(BitmapEx const& rBitmapEx) const
  29 {
  30     SAL_INFO("vcl.gdi", "BitmapFastScaleFilter::execute()");
  31
  32     Bitmap aBitmap(rBitmapEx.GetBitmap());
  33
  34     const Size aSizePix(aBitmap.GetSizePixel());
  35     const sal_Int32 nNewWidth = basegfx::fround(aSizePix.Width() * mfScaleX);
  36     const sal_Int32 nNewHeight = basegfx::fround(aSizePix.Height() * mfScaleY);
  37     bool bRet = false;
  38
  39     SAL_INFO("vcl.gdi", "New width: " << nNewWidth << "\nNew height: " << nNewHeight);
  40
  41     if (nNewWidth > 0 && nNewHeight > 0)
  42     {
  43         BitmapScopedReadAccess pReadAcc(aBitmap);
  44
  45         if (pReadAcc)
  46         {
  47             Bitmap aNewBmp(Size(nNewWidth, nNewHeight), aBitmap.getPixelFormat(),
  48                            &pReadAcc->GetPalette());
  49             BitmapScopedWriteAccess pWriteAcc(aNewBmp);
  50
  51             if (pWriteAcc)
  52             {
  53                 const sal_Int32 nScanlineSize = pWriteAcc->GetScanlineSize();
  54                 const sal_Int32 nNewHeight1 = nNewHeight - 1;
  55
  56                 if (nNewWidth && nNewHeight)
  57                 {
  58                     const double nWidth = pReadAcc->Width();
  59                     const double nHeight = pReadAcc->Height();
  60                     std::unique_ptr<sal_Int32[]> pLutX(new sal_Int32[nNewWidth]);
  61                     std::unique_ptr<sal_Int32[]> pLutY(new sal_Int32[nNewHeight]);
  62
  63                     for (sal_Int32 nX = 0; nX < nNewWidth; nX++)
  64                     {
  65                         pLutX[nX] = sal_Int32(nX * nWidth / nNewWidth);
  66                     }
  67
  68                     for (sal_Int32 nY = 0; nY < nNewHeight; nY++)
  69                     {
  70                         pLutY[nY] = sal_Int32(nY * nHeight / nNewHeight);
  71                     }
  72
  73                     sal_Int32 nActY = 0;
  74                     while (nActY < nNewHeight)
  75                     {
  76                         sal_Int32 nMapY = pLutY[nActY];
  77                         Scanline pScanline = pWriteAcc->GetScanline(nActY);
  78                         Scanline pScanlineRead = pReadAcc->GetScanline(nMapY);
  79
  80                         for (sal_Int32 nX = 0; nX < nNewWidth; nX++)
  81                         {
  82                             pWriteAcc->SetPixelOnData(
  83                                 pScanline, nX,
  84                                 pReadAcc->GetPixelFromData(pScanlineRead, pLutX[nX]));
  85                         }
  86
  87                         while ((nActY < nNewHeight1) && (pLutY[nActY + 1] == nMapY))
  88                         {
  89                             memcpy(pWriteAcc->GetScanline(nActY + 1), pWriteAcc->GetScanline(nActY),
  90                                    nScanlineSize);
  91                             nActY++;
  92                         }
  93                         nActY++;
  94                     }
  95
  96                     bRet = true;
  97                 }
  98
  99                 pWriteAcc.reset();
 100             }
 101             pReadAcc.reset();
 102
 103             if (bRet)
 104             {
 105                 aBitmap.ReassignWithSize(aNewBmp);
 106                 SAL_INFO("vcl.gdi", "Bitmap size: " << aBitmap.GetSizePixel());
 107             }
 108             else
 109             {
 110                 SAL_WARN("vcl.gdi", "no resize");
 111             }
 112         }
 113     }
 114
 115     AlphaMask aMask(rBitmapEx.GetAlphaMask());
 116
 117     if (bRet && !aMask.IsEmpty())
 118         bRet = aMask.Scale(Size(nNewWidth, nNewHeight), BmpScaleFlag::Fast);
 119
 120     SAL_WARN_IF(!aMask.IsEmpty() && aBitmap.GetSizePixel() != aMask.GetSizePixel(), "vcl",
 121                 "BitmapEx::Scale(): size mismatch for bitmap and alpha mask.");
 122
 123     if (bRet)
 124         return BitmapEx(aBitmap, aMask);
 125
 126     return BitmapEx();
 127 }
 128
 129 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */