text: /*
   * Copyright (C) 2009 Apple Inc. All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in the
   *    documentation and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE INC. OR
   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
   * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
   * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
   * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_GRAPHICS_INTERPOLATION_SPACE_H_
  #define THIRD_PARTY_BLINK_RENDERER_PLATFORM_GRAPHICS_INTERPOLATION_SPACE_H_
  
  #include "third_party/blink/renderer/platform/graphics/color.h"
  #include "third_party/skia/include/core/SkRefCnt.h"
  
  class SkColorFilter;
  
  namespace blink {
  
  enum InterpolationSpace {
    // Interpolation is performed on (assumed to be sRGB) pixel values directly,
    // so a halfway interpolation of 0 and 255 is 127.
    kInterpolationSpaceSRGB,
    // Interpolation is performed in linear physical value space, so a halfway
    // interpolation of 0 and 255 is 188.
    kInterpolationSpaceLinear
  };
  
  namespace interpolation_space_utilities {
  
  // Convert a Color assumed to be in the |src_interpolation_space| into the
  // |dst_interpolation_space|.
  Color ConvertColor(
      const Color& src_color,
      InterpolationSpace dst_interpolation_space,
      InterpolationSpace src_interpolation_space = kInterpolationSpaceSRGB);
  
  // Create a color filter that will convert from |src_interpolation_space| into
  // |dst_interpolation_space|.
  sk_sp<SkColorFilter> CreateInterpolationSpaceFilter(
      InterpolationSpace src_interpolation_space,
      InterpolationSpace dst_interpolation_space);
  
  }  // namespace interpolation_space_utilities
  
  }  // namespace blink
  
  #endif  // THIRD_PARTY_BLINK_RENDERER_PLATFORM_GRAPHICS_INTERPOLATION_SPACE_H_
  