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/*
* Copyright 2017 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkEncodedOrigin_DEFINED
#define SkEncodedOrigin_DEFINED
#include "include/core/SkMatrix.h"
// These values match the orientation www.exif.org/Exif2-2.PDF.
enum SkEncodedOrigin {
kTopLeft_SkEncodedOrigin = 1, // Default
kTopRight_SkEncodedOrigin = 2, // Reflected across y-axis
kBottomRight_SkEncodedOrigin = 3, // Rotated 180
kBottomLeft_SkEncodedOrigin = 4, // Reflected across x-axis
kLeftTop_SkEncodedOrigin = 5, // Reflected across x-axis, Rotated 90 CCW
kRightTop_SkEncodedOrigin = 6, // Rotated 90 CW
kRightBottom_SkEncodedOrigin = 7, // Reflected across x-axis, Rotated 90 CW
kLeftBottom_SkEncodedOrigin = 8, // Rotated 90 CCW
kDefault_SkEncodedOrigin = kTopLeft_SkEncodedOrigin,
kLast_SkEncodedOrigin = kLeftBottom_SkEncodedOrigin,
};
/**
* Given an encoded origin and the width and height of the source data, returns a matrix
* that transforms the source rectangle with upper left corner at [0, 0] and origin to a correctly
* oriented destination rectangle of [0, 0, w, h].
*/
static inline SkMatrix SkEncodedOriginToMatrix(SkEncodedOrigin origin, int w, int h) {
switch (origin) {
case kTopLeft_SkEncodedOrigin: return SkMatrix::I();
case kTopRight_SkEncodedOrigin: return SkMatrix::MakeAll(-1, 0, w, 0, 1, 0, 0, 0, 1);
case kBottomRight_SkEncodedOrigin: return SkMatrix::MakeAll(-1, 0, w, 0, -1, h, 0, 0, 1);
case kBottomLeft_SkEncodedOrigin: return SkMatrix::MakeAll( 1, 0, 0, 0, -1, h, 0, 0, 1);
case kLeftTop_SkEncodedOrigin: return SkMatrix::MakeAll( 0, 1, 0, 1, 0, 0, 0, 0, 1);
case kRightTop_SkEncodedOrigin: return SkMatrix::MakeAll( 0, -1, w, 1, 0, 0, 0, 0, 1);
case kRightBottom_SkEncodedOrigin: return SkMatrix::MakeAll( 0, -1, w, -1, 0, h, 0, 0, 1);
case kLeftBottom_SkEncodedOrigin: return SkMatrix::MakeAll( 0, 1, 0, -1, 0, h, 0, 0, 1);
}
SK_ABORT("Unexpected origin");
}
/**
* Return true if the encoded origin includes a 90 degree rotation, in which case the width
* and height of the source data are swapped relative to a correctly oriented destination.
*/
static inline bool SkEncodedOriginSwapsWidthHeight(SkEncodedOrigin origin) {
return origin >= kLeftTop_SkEncodedOrigin;
}
#endif // SkEncodedOrigin_DEFINED