OLD | NEW |
---|---|
(Empty) | |
1 /* | |
2 * Copyright 2016 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 /* | |
9 * Copyright (C) 2015 Google Inc. All rights reserved. | |
10 * | |
11 * Redistribution and use in source and binary forms, with or without | |
12 * modification, are permitted provided that the following conditions | |
13 * are met: | |
14 * 1. Redistributions of source code must retain the above copyright | |
15 * notice, this list of conditions and the following disclaimer. | |
16 * 2. Redistributions in binary form must reproduce the above copyright | |
17 * notice, this list of conditions and the following disclaimer in the | |
18 * documentation and/or other materials provided with the distribution. | |
19 * | |
20 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY | |
21 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR | |
23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR | |
24 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |
25 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | |
26 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | |
27 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY | |
28 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | |
30 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
31 */ | |
32 | |
33 #ifndef SkCodecAnimation_DEFINED | |
34 #define SkCodecAnimation_DEFINED | |
35 | |
36 #include "SkCodec.h" | |
37 #include "SkRect.h" | |
38 | |
39 class SkCodecAnimation { | |
40 public: | |
41 | |
42 // GIF and WebP support animation. The explanation below is in terms of GIF, | |
43 // but the same constants are used for WebP, too. | |
44 // GIFs have an optional 16-bit unsigned loop count that describes how an | |
45 // animated GIF should be cycled. If the loop count is absent, the animatio n | |
46 // cycles once; if it is 0, the animation cycles infinitely; otherwise the | |
47 // animation plays n + 1 cycles (where n is the specified loop count). If t he | |
48 // GIF decoder defaults to kAnimationLoopOnce in the absence of any loop cou nt | |
49 // and translates an explicit "0" loop count to kAnimationLoopInfinite, then we | |
50 // get a couple of nice side effects: | |
51 // * By making kAnimationLoopOnce be 0, we allow the animation cycling cod e in | |
52 // BitmapImage.cpp to avoid special-casing it, and simply treat all | |
msarett
2016/10/14 14:58:50
Reference to a chromium class?
scroggo_chromium
2016/10/14 19:56:00
Removed.
| |
53 // non-negative loop counts identically. | |
54 // * By making the other two constants negative, we avoid conflicts with a ny | |
55 // real loop count values. | |
56 static const int kAnimationLoopOnce = 0; | |
57 static const int kAnimationLoopInfinite = -1; | |
58 static const int kAnimationNone = -2; | |
59 | |
60 /** | |
61 * This specifies how the next frame is based on this frame. | |
62 * | |
63 * Names are based on the GIF 89a spec. | |
64 * | |
65 * The numbers correspond to values in a GIF. | |
66 */ | |
67 enum DisposalMethod { | |
68 /** | |
69 * The next frame should be drawn on top of this one. | |
70 * | |
71 * In a GIF, a value of 0 (not specified) is also treated as Keep. | |
72 */ | |
73 Keep_DisposalMethod = 1, | |
74 | |
75 /** | |
76 * Similar to Keep, except the area inside this frame's rectangle | |
77 * should be cleared to the BackGround color (transparent) before | |
78 * drawing the next frame. | |
79 */ | |
80 RestoreBGColor_DisposalMethod = 2, | |
81 | |
82 /** | |
83 * The next frame should be drawn on top of the previous frame - i.e. | |
84 * disregarding this one. | |
85 * | |
86 * In a GIF, a value of 4 is also treated as RestorePrevious. | |
87 */ | |
88 RestorePrevious_DisposalMethod = 3, | |
89 }; | |
90 | |
91 private: | |
92 SkCodecAnimation(); | |
93 }; | |
94 #endif // SkCodecAnimation_DEFINED | |
OLD | NEW |