gecko-dev/gfx/2d/ImageScaling.h

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#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(nullptr),
        mData(nullptr),
        mStride(0) {}

  ~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;
};

}  // namespace gfx
}  // namespace mozilla

#endif