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/*
* Copyright (C) 2025 Samuel Weinig <sam@webkit.org>
*
* 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. ``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
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* 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 <WebCore/CSSPropertyNames.h>
#include <WebCore/StyleValueTypes.h>
#include <wtf/PointerComparison.h>
#include <wtf/RefCounted.h>
#include <wtf/TZoneMalloc.h>
#include <wtf/Vector.h>
namespace WebCore {
namespace Style {
struct WillChange;
// <animateable-feature>
struct WillChangeAnimatableFeature {
// FIXME: This should be storing <custom-ident> for non-CSSPropertyID values to correctly implement computed value serialization.
// It should likely be a Variant<CSS::Keyword::ScrollPosition, CSS::Keyword::Contents, PropertyIdentifier, CustomIdentifier>;
enum class Feature: uint8_t {
ScrollPosition,
Contents,
Property,
};
static const int numCSSPropertyIDBits = 14;
static_assert(cssPropertyIDEnumValueCount <= (1 << numCSSPropertyIDBits), "CSSPropertyID should fit in 14 bits");
WillChangeAnimatableFeature(Feature, CSSPropertyID = CSSPropertyInvalid);
Feature m_feature { Feature::Property };
unsigned m_cssPropertyID : numCSSPropertyIDBits { CSSPropertyInvalid };
Feature feature() const { return m_feature; }
CSSPropertyID property() const { return feature() == Feature::Property ? static_cast<CSSPropertyID>(m_cssPropertyID) : CSSPropertyInvalid; }
static bool propertyCreatesStackingContext(CSSPropertyID);
static bool propertyTriggersCompositing(CSSPropertyID);
static bool propertyTriggersCompositingOnBoxesOnly(CSSPropertyID);
template<typename... F> decltype(auto) switchOn(F&&... f) const
{
auto visitor = WTF::makeVisitor(std::forward<F>(f)...);
switch (m_feature) {
case Feature::ScrollPosition:
return visitor(CSS::Keyword::ScrollPosition { });
case Feature::Contents:
return visitor(CSS::Keyword::Contents { });
case Feature::Property:
return visitor(PropertyIdentifier { property() });
}
RELEASE_ASSERT_NOT_REACHED();
}
bool operator==(const WillChangeAnimatableFeature&) const = default;
};
// <animateable-feature>#
struct WillChangeAnimatableFeatures {
using Feature = WillChangeAnimatableFeature::Feature;
using value_type = Vector<WillChangeAnimatableFeature, 1>::value_type;
using const_iterator = Vector<WillChangeAnimatableFeature, 1>::const_iterator;
WillChangeAnimatableFeatures() : m_data { Data::create() } { }
WillChangeAnimatableFeatures(Feature feature, CSSPropertyID propertyID = CSSPropertyInvalid) : m_data { Data::create(feature, propertyID) } { }
bool containsScrollPosition() const { return m_data->containsScrollPosition(); }
bool containsContents() const { return m_data->containsContents(); }
bool containsProperty(CSSPropertyID property) const { return m_data->containsProperty(property); }
bool createsContainingBlockForAbsolutelyPositioned(bool isRootElement) const { return m_data->createsContainingBlockForAbsolutelyPositioned(isRootElement); }
bool createsContainingBlockForOutOfFlowPositioned(bool isRootElement) const { return m_data->createsContainingBlockForOutOfFlowPositioned(isRootElement); }
bool canCreateStackingContext() const { return m_data->canCreateStackingContext(); }
bool canBeBackdropRoot() const { return m_data->canBeBackdropRoot(); }
bool canTriggerCompositing() const { return m_data->canTriggerCompositing(); }
bool canTriggerCompositingOnInline() const { return m_data->canTriggerCompositingOnInline(); }
void addFeature(Feature feature, CSSPropertyID property = CSSPropertyInvalid) { m_data->addFeature(feature, property); }
const_iterator begin() const { return m_data->begin(); }
const_iterator end() const { return m_data->end(); }
private:
friend struct WillChange;
class Data : public RefCounted<Data> {
WTF_MAKE_TZONE_ALLOCATED(Data);
public:
static Ref<Data> create() { return adoptRef(*new Data); }
static Ref<Data> create(Feature feature, CSSPropertyID propertyID) { return adoptRef(*new Data(feature, propertyID)); }
bool containsScrollPosition() const;
bool containsContents() const;
bool containsProperty(CSSPropertyID) const;
bool createsContainingBlockForAbsolutelyPositioned(bool isRootElement) const;
bool createsContainingBlockForOutOfFlowPositioned(bool isRootElement) const;
bool canCreateStackingContext() const { return m_canCreateStackingContext; }
bool canBeBackdropRoot() const;
bool canTriggerCompositing() const { return m_canTriggerCompositing; }
bool canTriggerCompositingOnInline() const { return m_canTriggerCompositingOnInline; }
void addFeature(Feature, CSSPropertyID);
const_iterator begin() const { return m_animatableFeatures.begin(); }
const_iterator end() const { return m_animatableFeatures.end(); }
bool operator==(const Data&) const;
private:
Data() { }
Data(Feature feature, CSSPropertyID propertyID) { addFeature(feature, propertyID); }
Vector<WillChangeAnimatableFeature, 1> m_animatableFeatures;
bool m_canCreateStackingContext { false };
bool m_canTriggerCompositing { false };
bool m_canTriggerCompositingOnInline { false };
};
WillChangeAnimatableFeatures(Ref<Data> data) : m_data { WTFMove(data) } { }
Ref<Data> m_data;
};
// <'will-change'> = auto | <animateable-feature>#
// https://drafts.csswg.org/css-will-change/#propdef-will-change
struct WillChange {
WillChange(CSS::Keyword::Auto) : m_data { nullptr} { }
WillChange(WillChangeAnimatableFeatures&& animateableFeatures) : m_data { WTFMove(animateableFeatures.m_data) } { }
WillChange(WillChangeAnimatableFeature::Feature feature, CSSPropertyID propertyID = CSSPropertyInvalid) : m_data { WillChangeAnimatableFeatures::Data::create(feature, propertyID) } { }
bool isAuto() const { return !m_data; }
bool isAnimateableFeatures() const { return !!m_data; }
template<typename... F> decltype(auto) switchOn(F&&... f) const
{
auto visitor = WTF::makeVisitor(std::forward<F>(f)...);
if (isAuto())
return visitor(CSS::Keyword::Auto { });
return visitor(WillChangeAnimatableFeatures { *m_data });
}
bool containsScrollPosition() const { return m_data && m_data->containsScrollPosition(); }
bool containsContents() const { return m_data && m_data->containsContents(); }
bool containsProperty(CSSPropertyID property) const { return m_data && m_data->containsProperty(property); }
bool createsContainingBlockForAbsolutelyPositioned(bool isRootElement) const { return m_data && m_data->createsContainingBlockForAbsolutelyPositioned(isRootElement); }
bool createsContainingBlockForOutOfFlowPositioned(bool isRootElement) const { return m_data && m_data->createsContainingBlockForOutOfFlowPositioned(isRootElement); }
bool canCreateStackingContext() const { return m_data && m_data->canCreateStackingContext(); }
bool canBeBackdropRoot() const { return m_data && m_data->canBeBackdropRoot(); }
bool canTriggerCompositing() const { return m_data && m_data->canTriggerCompositing(); }
bool canTriggerCompositingOnInline() const { return m_data && m_data->canTriggerCompositingOnInline(); }
bool operator==(const WillChange& other) const
{
return arePointingToEqualData(m_data, other.m_data);
}
private:
RefPtr<WillChangeAnimatableFeatures::Data> m_data;
};
// MARK: - Conversion
template<> struct CSSValueConversion<WillChange> { auto operator()(BuilderState&, const CSSValue&) -> WillChange; };
} // namespace Style
} // namespace WebCore
DEFINE_COMMA_SEPARATED_RANGE_LIKE_CONFORMANCE(WebCore::Style::WillChangeAnimatableFeatures)
DEFINE_VARIANT_LIKE_CONFORMANCE(WebCore::Style::WillChangeAnimatableFeature);
DEFINE_VARIANT_LIKE_CONFORMANCE(WebCore::Style::WillChange);
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