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 "include/core/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 | } |
45 | |
46 | |
47 | #endif // SkEncodedOrigin_DEFINED |
48 | |