image/Orientation.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #ifndef mozilla_image_Orientation_h
   7 #define mozilla_image_Orientation_h
   8
   9 #include <stdint.h>
  10
  11 namespace mozilla {
  12 namespace image {
  13
  14 enum class Angle : uint8_t { D0, D90, D180, D270 };
  15
  16 enum class Flip : uint8_t { Unflipped, Horizontal };
  17
  18 /**
  19  * A struct that describes an image's orientation as a rotation optionally
  20  * followed by a reflection. This may be used to be indicate an image's inherent
  21  * orientation or a desired orientation for the image.
  22  */
  23 struct Orientation {
  24   explicit Orientation(Angle aRotation = Angle::D0,
  25                        Flip mFlip = Flip::Unflipped)
  26       : rotation(aRotation), flip(mFlip) {}
  27
  28   bool IsIdentity() const {
  29     return (rotation == Angle::D0) && (flip == Flip::Unflipped);
  30   }
  31
  32   bool SwapsWidthAndHeight() const {
  33     return (rotation == Angle::D90) || (rotation == Angle::D270);
  34   }
  35
  36   bool operator==(const Orientation& aOther) const {
  37     return (rotation == aOther.rotation) && (flip == aOther.flip);
  38   }
  39
  40   bool operator!=(const Orientation& aOther) const {
  41     return !(*this == aOther);
  42   }
  43
  44   Angle rotation;
  45   Flip flip;
  46 };
  47
  48 }  // namespace image
  49 }  // namespace mozilla
  50
  51 #endif  // mozilla_image_Orientation_h