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/*
* Copyright (C) 2015 Apple 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 INC. AND ITS CONTRIBUTORS ``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 INC. OR ITS 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.
*/
#pragma once
#include "CSSPropertyNames.h"
#include <wtf/RefCounted.h>
#include <wtf/Vector.h>
namespace WebCore {
class WillChangeData : public RefCounted<WillChangeData> {
WTF_MAKE_FAST_ALLOCATED;
public:
static Ref<WillChangeData> create()
{
return adoptRef(*new WillChangeData);
}
bool operator==(const WillChangeData&) const;
bool operator!=(const WillChangeData& o) const
{
return !(*this == o);
}
bool isAuto() const { return m_animatableFeatures.isEmpty(); }
size_t numFeatures() const { return m_animatableFeatures.size(); }
bool containsScrollPosition() const;
bool containsContents() const;
bool containsProperty(CSSPropertyID) const;
bool createsContainingBlockForAbsolutelyPositioned() const;
bool createsContainingBlockForOutOfFlowPositioned() const;
bool canCreateStackingContext() const { return m_canCreateStackingContext; }
bool canTriggerCompositing() const { return m_canTriggerCompositing; }
bool canTriggerCompositingOnInline() const { return m_canTriggerCompositingOnInline; }
enum Feature {
ScrollPosition,
Contents,
Property,
Invalid
};
void addFeature(Feature, CSSPropertyID = CSSPropertyInvalid);
typedef std::pair<Feature, CSSPropertyID> FeaturePropertyPair;
FeaturePropertyPair featureAt(size_t) const;
static bool propertyCreatesStackingContext(CSSPropertyID);
private:
WillChangeData()
{
}
struct AnimatableFeature {
static const int numCSSPropertyIDBits = 14;
static_assert(numCSSProperties < (1 << numCSSPropertyIDBits), "CSSPropertyID should fit in 14_bits");
unsigned m_feature : 2;
unsigned m_cssPropertyID : numCSSPropertyIDBits;
Feature feature() const
{
return static_cast<Feature>(m_feature);
}
CSSPropertyID property() const
{
return feature() == Property ? static_cast<CSSPropertyID>(m_cssPropertyID) : CSSPropertyInvalid;
}
FeaturePropertyPair featurePropertyPair() const
{
return FeaturePropertyPair(feature(), property());
}
AnimatableFeature(Feature willChange, CSSPropertyID willChangeProperty = CSSPropertyInvalid)
{
switch (willChange) {
case Property:
ASSERT(willChangeProperty != CSSPropertyInvalid);
m_cssPropertyID = willChangeProperty;
FALLTHROUGH;
case ScrollPosition:
case Contents:
m_feature = static_cast<unsigned>(willChange);
break;
case Invalid:
ASSERT_NOT_REACHED();
break;
}
}
bool operator==(const AnimatableFeature& other) const
{
return m_feature == other.m_feature && m_cssPropertyID == other.m_cssPropertyID;
}
};
Vector<AnimatableFeature, 1> m_animatableFeatures;
bool m_canCreateStackingContext { false };
bool m_canTriggerCompositing { false };
bool m_canTriggerCompositingOnInline { false };
};
} // namespace WebCore
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