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/*
* Copyright (C) 2015 Google Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef ImageAnimation_h
#define ImageAnimation_h
namespace blink {
// GIF and WebP support animation. The explanation below is in terms of GIF,
// but the same constants are used for WebP, too.
// GIFs have an optional 16-bit unsigned loop count that describes how an
// animated GIF should be cycled. If the loop count is absent, the animation
// cycles once; if it is 0, the animation cycles infinitely; otherwise the
// animation plays n + 1 cycles (where n is the specified loop count). If the
// GIF decoder defaults to cAnimationLoopOnce in the absence of any loop count
// and translates an explicit "0" loop count to cAnimationLoopInfinite, then we
// get a couple of nice side effects:
// * By making cAnimationLoopOnce be 0, we allow the animation cycling code in
// BitmapImage.cpp to avoid special-casing it, and simply treat all
// non-negative loop counts identically.
// * By making the other two constants negative, we avoid conflicts with any
// real loop count values.
const int cAnimationLoopOnce = 0;
const int cAnimationLoopInfinite = -1;
const int cAnimationNone = -2;
} // namespace blink
#endif
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