diff options
| -rw-r--r-- | image/FrameTimeout.h | 119 | ||||
| -rw-r--r-- | image/imgFrame.h | 100 |
2 files changed, 119 insertions, 100 deletions
diff --git a/image/FrameTimeout.h b/image/FrameTimeout.h new file mode 100644 index 000000000..4070bba65 --- /dev/null +++ b/image/FrameTimeout.h @@ -0,0 +1,119 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- + * + * This Source Code Form is subject to the terms of the Mozilla Public + * License, v. 2.0. If a copy of the MPL was not distributed with this + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ + +#ifndef mozilla_image_FrameTimeout_h +#define mozilla_image_FrameTimeout_h + +#include <stdint.h> +#include "mozilla/Assertions.h" + +namespace mozilla { +namespace image { + +/** + * FrameTimeout wraps a frame timeout value (measured in milliseconds) after + * first normalizing it. This normalization is necessary because some tools + * generate incorrect frame timeout values which we nevertheless have to + * support. For this reason, code that deals with frame timeouts should always + * use a FrameTimeout value rather than the raw value from the image header. + */ +struct FrameTimeout +{ + /** + * @return a FrameTimeout of zero. This should be used only for math + * involving FrameTimeout values. You can't obtain a zero FrameTimeout from + * FromRawMilliseconds(). + */ + static FrameTimeout Zero() { return FrameTimeout(0); } + + /// @return an infinite FrameTimeout. + static FrameTimeout Forever() { return FrameTimeout(-1); } + + /// @return a FrameTimeout obtained by normalizing a raw timeout value. + static FrameTimeout FromRawMilliseconds(int32_t aRawMilliseconds) + { + // Normalize all infinite timeouts to the same value. + if (aRawMilliseconds < 0) { + return FrameTimeout::Forever(); + } + + // Very small timeout values are problematic for two reasons: we don't want + // to burn energy redrawing animated images extremely fast, and broken tools + // generate these values when they actually want a "default" value, so such + // images won't play back right without normalization. For some context, + // see bug 890743, bug 125137, bug 139677, and bug 207059. The historical + // behavior of IE and Opera was: + // IE 6/Win: + // 10 - 50ms is normalized to 100ms. + // >50ms is used unnormalized. + // Opera 7 final/Win: + // 10ms is normalized to 100ms. + // >10ms is used unnormalized. + if (aRawMilliseconds >= 0 && aRawMilliseconds <= 10 ) { + return FrameTimeout(100); + } + + // The provided timeout value is OK as-is. + return FrameTimeout(aRawMilliseconds); + } + + bool operator==(const FrameTimeout& aOther) const + { + return mTimeout == aOther.mTimeout; + } + + bool operator!=(const FrameTimeout& aOther) const { return !(*this == aOther); } + + FrameTimeout operator+(const FrameTimeout& aOther) + { + if (*this == Forever() || aOther == Forever()) { + return Forever(); + } + + return FrameTimeout(mTimeout + aOther.mTimeout); + } + + FrameTimeout& operator+=(const FrameTimeout& aOther) + { + *this = *this + aOther; + return *this; + } + + /** + * @return this FrameTimeout's value in milliseconds. Illegal to call on a + * an infinite FrameTimeout value. + */ + uint32_t AsMilliseconds() const + { + if (*this == Forever()) { + MOZ_ASSERT_UNREACHABLE("Calling AsMilliseconds() on an infinite FrameTimeout"); + return 100; // Fail to something sane. + } + + return uint32_t(mTimeout); + } + + /** + * @return this FrameTimeout value encoded so that non-negative values + * represent a timeout in milliseconds, and -1 represents an infinite + * timeout. + * + * XXX(seth): This is a backwards compatibility hack that should be removed. + */ + int32_t AsEncodedValueDeprecated() const { return mTimeout; } + +private: + explicit FrameTimeout(int32_t aTimeout) + : mTimeout(aTimeout) + { } + + int32_t mTimeout; +}; + +} // namespace image +} // namespace mozilla + +#endif // mozilla_image_FrameTimeout_h diff --git a/image/imgFrame.h b/image/imgFrame.h index 32aabacae..928f6ad86 100644 --- a/image/imgFrame.h +++ b/image/imgFrame.h @@ -30,106 +30,6 @@ enum class Opacity : uint8_t { }; /** - * FrameTimeout wraps a frame timeout value (measured in milliseconds) after - * first normalizing it. This normalization is necessary because some tools - * generate incorrect frame timeout values which we nevertheless have to - * support. For this reason, code that deals with frame timeouts should always - * use a FrameTimeout value rather than the raw value from the image header. - */ -struct FrameTimeout -{ - /** - * @return a FrameTimeout of zero. This should be used only for math - * involving FrameTimeout values. You can't obtain a zero FrameTimeout from - * FromRawMilliseconds(). - */ - static FrameTimeout Zero() { return FrameTimeout(0); } - - /// @return an infinite FrameTimeout. - static FrameTimeout Forever() { return FrameTimeout(-1); } - - /// @return a FrameTimeout obtained by normalizing a raw timeout value. - static FrameTimeout FromRawMilliseconds(int32_t aRawMilliseconds) - { - // Normalize all infinite timeouts to the same value. - if (aRawMilliseconds < 0) { - return FrameTimeout::Forever(); - } - - // Very small timeout values are problematic for two reasons: we don't want - // to burn energy redrawing animated images extremely fast, and broken tools - // generate these values when they actually want a "default" value, so such - // images won't play back right without normalization. For some context, - // see bug 890743, bug 125137, bug 139677, and bug 207059. The historical - // behavior of IE and Opera was: - // IE 6/Win: - // 10 - 50ms is normalized to 100ms. - // >50ms is used unnormalized. - // Opera 7 final/Win: - // 10ms is normalized to 100ms. - // >10ms is used unnormalized. - if (aRawMilliseconds >= 0 && aRawMilliseconds <= 10 ) { - return FrameTimeout(100); - } - - // The provided timeout value is OK as-is. - return FrameTimeout(aRawMilliseconds); - } - - bool operator==(const FrameTimeout& aOther) const - { - return mTimeout == aOther.mTimeout; - } - - bool operator!=(const FrameTimeout& aOther) const { return !(*this == aOther); } - - FrameTimeout operator+(const FrameTimeout& aOther) - { - if (*this == Forever() || aOther == Forever()) { - return Forever(); - } - - return FrameTimeout(mTimeout + aOther.mTimeout); - } - - FrameTimeout& operator+=(const FrameTimeout& aOther) - { - *this = *this + aOther; - return *this; - } - - /** - * @return this FrameTimeout's value in milliseconds. Illegal to call on a - * an infinite FrameTimeout value. - */ - uint32_t AsMilliseconds() const - { - if (*this == Forever()) { - MOZ_ASSERT_UNREACHABLE("Calling AsMilliseconds() on an infinite FrameTimeout"); - return 100; // Fail to something sane. - } - - return uint32_t(mTimeout); - } - - /** - * @return this FrameTimeout value encoded so that non-negative values - * represent a timeout in milliseconds, and -1 represents an infinite - * timeout. - * - * XXX(seth): This is a backwards compatibility hack that should be removed. - */ - int32_t AsEncodedValueDeprecated() const { return mTimeout; } - -private: - explicit FrameTimeout(int32_t aTimeout) - : mTimeout(aTimeout) - { } - - int32_t mTimeout; -}; - -/** * AnimationData contains all of the information necessary for using an imgFrame * as part of an animation. * |