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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* 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_image_Orientation_h
#define mozilla_image_Orientation_h
#include <stdint.h>
#include "mozilla/gfx/Rect.h"
namespace mozilla {
// Pixel values in an image considering orientation metadata, such as the size
// of an image as seen by consumers of the image.
//
// Any public methods on RasterImage that use untyped units are interpreted as
// oriented pixels.
struct OrientedPixel {};
template <>
struct IsPixel<OrientedPixel> : std::true_type {};
typedef gfx::IntPointTyped<OrientedPixel> OrientedIntPoint;
typedef gfx::IntSizeTyped<OrientedPixel> OrientedIntSize;
typedef gfx::IntRectTyped<OrientedPixel> OrientedIntRect;
// Pixel values in an image ignoring orientation metadata, such as are stored
// in surfaces and the raw pixel data in the image.
struct UnorientedPixel {};
template <>
struct IsPixel<UnorientedPixel> : std::true_type {};
typedef gfx::IntPointTyped<UnorientedPixel> UnorientedIntPoint;
typedef gfx::IntSizeTyped<UnorientedPixel> UnorientedIntSize;
typedef gfx::IntRectTyped<UnorientedPixel> UnorientedIntRect;
namespace image {
enum class Angle : uint8_t { D0, D90, D180, D270 };
enum class Flip : uint8_t { Unflipped, Horizontal };
/**
* A struct that describes an image's orientation as a rotation optionally
* followed by a reflection. This may be used to be indicate an image's inherent
* orientation or a desired orientation for the image.
*
* When flipFirst = true, this indicates that the reflection is applied before
* the rotation. (This is used by OrientedImage to represent the inverse of an
* underlying image's Orientation.)
*/
struct Orientation {
explicit Orientation(Angle aRotation = Angle::D0,
Flip aFlip = Flip::Unflipped, bool aFlipFirst = false)
: rotation(aRotation), flip(aFlip), flipFirst(aFlipFirst) {}
Orientation Reversed() const {
return Orientation(InvertAngle(rotation), flip, !flipFirst);
}
bool IsIdentity() const {
return (rotation == Angle::D0) && (flip == Flip::Unflipped);
}
bool SwapsWidthAndHeight() const {
return (rotation == Angle::D90) || (rotation == Angle::D270);
}
bool operator==(const Orientation& aOther) const {
return rotation == aOther.rotation && flip == aOther.flip &&
flipFirst == aOther.flipFirst;
}
bool operator!=(const Orientation& aOther) const {
return !(*this == aOther);
}
OrientedIntSize ToOriented(const UnorientedIntSize& aSize) const {
if (SwapsWidthAndHeight()) {
return OrientedIntSize(aSize.height, aSize.width);
} else {
return OrientedIntSize(aSize.width, aSize.height);
}
}
UnorientedIntSize ToUnoriented(const OrientedIntSize& aSize) const {
if (SwapsWidthAndHeight()) {
return UnorientedIntSize(aSize.height, aSize.width);
} else {
return UnorientedIntSize(aSize.width, aSize.height);
}
}
static Angle InvertAngle(Angle aAngle) {
switch (aAngle) {
case Angle::D90:
return Angle::D270;
case Angle::D270:
return Angle::D90;
default:
return aAngle;
}
}
Angle rotation;
Flip flip;
bool flipFirst;
};
} // namespace image
} // namespace mozilla
#endif // mozilla_image_Orientation_h