1 /* 2 * Copyright 2017 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #ifndef SkEncodedOrigin_DEFINED 9 #define SkEncodedOrigin_DEFINED 10 11 #include "SkMatrix.h" 12 13 // These values match the orientation www.exif.org/Exif2-2.PDF. 14 enum SkEncodedOrigin { 15 kTopLeft_SkEncodedOrigin = 1, // Default 16 kTopRight_SkEncodedOrigin = 2, // Reflected across y-axis 17 kBottomRight_SkEncodedOrigin = 3, // Rotated 180 18 kBottomLeft_SkEncodedOrigin = 4, // Reflected across x-axis 19 kLeftTop_SkEncodedOrigin = 5, // Reflected across x-axis, Rotated 90 CCW 20 kRightTop_SkEncodedOrigin = 6, // Rotated 90 CW 21 kRightBottom_SkEncodedOrigin = 7, // Reflected across x-axis, Rotated 90 CW 22 kLeftBottom_SkEncodedOrigin = 8, // Rotated 90 CCW 23 kDefault_SkEncodedOrigin = kTopLeft_SkEncodedOrigin, 24 kLast_SkEncodedOrigin = kLeftBottom_SkEncodedOrigin, 25 }; 26 27 /** 28 * Given an encoded origin and the width and height of the source data, returns a matrix 29 * that transforms the source rectangle [0, 0, w, h] to a correctly oriented destination 30 * rectangle, with the upper left corner still at [0, 0]. 31 */ 32 static inline SkMatrix SkEncodedOriginToMatrix(SkEncodedOrigin origin, int w, int h) { 33 switch (origin) { 34 case kTopLeft_SkEncodedOrigin: return SkMatrix::I(); 35 case kTopRight_SkEncodedOrigin: return SkMatrix::MakeAll(-1, 0, w, 0, 1, 0, 0, 0, 1); 36 case kBottomRight_SkEncodedOrigin: return SkMatrix::MakeAll(-1, 0, w, 0, -1, h, 0, 0, 1); 37 case kBottomLeft_SkEncodedOrigin: return SkMatrix::MakeAll( 1, 0, 0, 0, -1, h, 0, 0, 1); 38 case kLeftTop_SkEncodedOrigin: return SkMatrix::MakeAll( 0, 1, 0, 1, 0, 0, 0, 0, 1); 39 case kRightTop_SkEncodedOrigin: return SkMatrix::MakeAll( 0, -1, h, 1, 0, 0, 0, 0, 1); 40 case kRightBottom_SkEncodedOrigin: return SkMatrix::MakeAll( 0, -1, h, -1, 0, w, 0, 0, 1); 41 case kLeftBottom_SkEncodedOrigin: return SkMatrix::MakeAll( 0, 1, 0, -1, 0, w, 0, 0, 1); 42 } 43 SK_ABORT("Unexpected origin"); 44 return SkMatrix::I(); 45 } 46 47 48 #endif // SkEncodedOrigin_DEFINED 49
