gecko/gfx/2d/ImageScaling.h

/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
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 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
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 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
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 * Software distributed under the License is distributed on an "AS IS" basis,
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 * The Original Code is Mozilla Corporation code.
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 * The Initial Developer of the Original Code is Mozilla Foundation.
 * Portions created by the Initial Developer are Copyright (C) 2011
 * the Initial Developer. All Rights Reserved.
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 * Contributor(s):
 *   Bas Schouten <bschouten@mozilla.com>
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 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
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#ifndef _MOZILLA_GFX_IMAGESCALING_H
#define _MOZILLA_GFX_IMAGESCALING_H

#include "Types.h"

#include <vector>
#include "Point.h"

namespace mozilla {
namespace gfx {

class ImageHalfScaler
{
public:
  ImageHalfScaler(uint8_t *aData, int32_t aStride, const IntSize &aSize)
    : mOrigData(aData), mOrigStride(aStride), mOrigSize(aSize)
    , mDataStorage(NULL)
  {
  }

  ~ImageHalfScaler()
  {
    delete [] mDataStorage;
  }

  void ScaleForSize(const IntSize &aSize);

  uint8_t *GetScaledData() const { return mData; }
  IntSize GetSize() const { return mSize; }
  uint32_t GetStride() const { return mStride; }

private:
  void HalfImage2D(uint8_t *aSource, int32_t aSourceStride, const IntSize &aSourceSize,
                   uint8_t *aDest, uint32_t aDestStride);
  void HalfImageVertical(uint8_t *aSource, int32_t aSourceStride, const IntSize &aSourceSize,
                         uint8_t *aDest, uint32_t aDestStride);
  void HalfImageHorizontal(uint8_t *aSource, int32_t aSourceStride, const IntSize &aSourceSize,
                           uint8_t *aDest, uint32_t aDestStride);

  // This is our SSE2 scaling function. Our destination must always be 16-byte
  // aligned and use a 16-byte aligned stride.
  void HalfImage2D_SSE2(uint8_t *aSource, int32_t aSourceStride, const IntSize &aSourceSize,
                        uint8_t *aDest, uint32_t aDestStride);
  void HalfImageVertical_SSE2(uint8_t *aSource, int32_t aSourceStride, const IntSize &aSourceSize,
                              uint8_t *aDest, uint32_t aDestStride);
  void HalfImageHorizontal_SSE2(uint8_t *aSource, int32_t aSourceStride, const IntSize &aSourceSize,
                                uint8_t *aDest, uint32_t aDestStride);

  void HalfImage2D_C(uint8_t *aSource, int32_t aSourceStride, const IntSize &aSourceSize,
                     uint8_t *aDest, uint32_t aDestStride);
  void HalfImageVertical_C(uint8_t *aSource, int32_t aSourceStride, const IntSize &aSourceSize,
                           uint8_t *aDest, uint32_t aDestStride);
  void HalfImageHorizontal_C(uint8_t *aSource, int32_t aSourceStride, const IntSize &aSourceSize,
                             uint8_t *aDest, uint32_t aDestStride);

  uint8_t *mOrigData;
  int32_t mOrigStride;
  IntSize mOrigSize;

  uint8_t *mDataStorage;
  // Guaranteed 16-byte aligned
  uint8_t *mData;
  IntSize mSize;
  // Guaranteed 16-byte aligned
  uint32_t mStride;
};

}
}

#endif