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LibWeb: Start transitions when affected properties change

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Co-authored-by: Matthew Olsson <matthewcolsson@gmail.com>
This commit is contained in:
Sam Atkins 2024-09-19 14:13:20 +01:00 committed by Andreas Kling
parent e544166977
commit a1fca1a7f3
Notes: github-actions[bot] 2024-09-22 04:42:46 +00:00 
Author: https://github.com/AtkinsSJ
Commit: https://github.com/LadybirdBrowser/ladybird/commit/a1fca1a7f3f
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/1442
8 changed files with 380 additions and 11 deletions
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5
Tests/LibWeb/Text/expected/css/transition-basics.txt Normal file
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@ -0,0 +1,5 @@
left starts at: 0px
shortly after starting, left is >= 0px? true and < 200px? true
half-way through, left is > 0px? true and < 200px? true
near the end, left is > 0px? true and < 200px? true
after the transition, left is: 200px

48
Tests/LibWeb/Text/input/css/transition-basics.html Normal file
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@ -0,0 +1,48 @@
<!DOCTYPE html>
<html>
<script src="../include.js"></script>
<style>
#box {
width: 200px;
height: 200px;
background-color: red;
position: absolute;
left: 0;
top: 0;
transition: left 1s linear;
}
#box.move {
left: 200px;
}
</style>
<div id="box"></div>
<script>
asyncTest(async done => {
let box = document.getElementById("box");
println(`left starts at: ${getComputedStyle(box).left}`);
box.classList.add("move");
setTimeout(() => {
let left = parseFloat(getComputedStyle(box).left);
println(`shortly after starting, left is >= 0px? ${left >= 0} and < 200px? ${left < 200}`);
}, 1);
setTimeout(() => {
let left = parseFloat(getComputedStyle(box).left);
println(`half-way through, left is > 0px? ${left > 0} and < 200px? ${left < 200}`);
}, 500);
setTimeout(() => {
let left = parseFloat(getComputedStyle(box).left);
println(`near the end, left is > 0px? ${left > 0} and < 200px? ${left < 200}`);
}, 950);
setTimeout(() => {
// FIXME: This is a hack to make it recompute the style, otherwise we get 0px for the left value.
// Figure out why!
box.style.top = "0px";
println(`after the transition, left is: ${getComputedStyle(box).left}`);
done();
}, 1050);
});
</script>
</html>

72
Userland/Libraries/LibWeb/CSS/CSSTransition.cpp
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@ -1,22 +1,30 @@
/*
* Copyright (c) 2024, Matthew Olsson <mattco@serenityos.org>.
* Copyright (c) 2024, Matthew Olsson <mattco@serenityos.org>
* Copyright (c) 2024, Sam Atkins <sam@ladybird.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibWeb/Animations/DocumentTimeline.h>
#include <LibWeb/Bindings/CSSTransitionPrototype.h>
#include <LibWeb/Bindings/Intrinsics.h>
#include <LibWeb/CSS/CSSStyleDeclaration.h>
#include <LibWeb/CSS/CSSTransition.h>
#include <LibWeb/CSS/Interpolation.h>
#include <LibWeb/DOM/Document.h>
#include <LibWeb/DOM/Element.h>
#include <LibWeb/HTML/Scripting/TemporaryExecutionContext.h>
namespace Web::CSS {
JS_DEFINE_ALLOCATOR(CSSTransition);
JS::NonnullGCPtr<CSSTransition> CSSTransition::create(JS::Realm& realm, PropertyID property_id, size_t transition_generation)
JS::NonnullGCPtr<CSSTransition> CSSTransition::start_a_transition(DOM::Element& element, PropertyID property_id, size_t transition_generation,
double start_time, double end_time, NonnullRefPtr<CSSStyleValue const> start_value, NonnullRefPtr<CSSStyleValue const> end_value,
NonnullRefPtr<CSSStyleValue const> reversing_adjusted_start_value, double reversing_shortening_factor)
{
return realm.heap().allocate<CSSTransition>(realm, realm, property_id, transition_generation);
auto& realm = element.realm();
return realm.heap().allocate<CSSTransition>(realm, realm, element, property_id, transition_generation, start_time, end_time, start_value, end_value, reversing_adjusted_start_value, reversing_shortening_factor);
}
Animations::AnimationClass CSSTransition::animation_class() const
@ -67,16 +75,53 @@ Optional<int> CSSTransition::class_specific_composite_order(JS::NonnullGCPtr<Ani
return {};
}
CSSTransition::CSSTransition(JS::Realm& realm, PropertyID property_id, size_t transition_generation)
CSSTransition::CSSTransition(JS::Realm& realm, DOM::Element& element, PropertyID property_id, size_t transition_generation,
double start_time, double end_time, NonnullRefPtr<CSSStyleValue const> start_value, NonnullRefPtr<CSSStyleValue const> end_value,
NonnullRefPtr<CSSStyleValue const> reversing_adjusted_start_value, double reversing_shortening_factor)
: Animations::Animation(realm)
, m_transition_property(property_id)
, m_transition_generation(transition_generation)
, m_start_time(start_time)
, m_end_time(end_time)
, m_start_value(move(start_value))
, m_end_value(move(end_value))
, m_reversing_adjusted_start_value(move(reversing_adjusted_start_value))
, m_reversing_shortening_factor(reversing_shortening_factor)
, m_keyframe_effect(Animations::KeyframeEffect::create(realm))
{
// FIXME:
// Transitions generated using the markup defined in this specification are not added to the global animation list
// when they are created. Instead, these animations are appended to the global animation list at the first moment
// when they transition out of the idle play state after being disassociated from their owning element. Transitions
// that have been disassociated from their owning element but are still idle do not have a defined composite order.
set_start_time(start_time - element.document().timeline()->current_time().value());
// Construct a KeyframesEffect for our animation
m_keyframe_effect->set_target(&element);
m_keyframe_effect->set_start_delay(start_time);
m_keyframe_effect->set_iteration_duration(m_end_time - start_time);
m_keyframe_effect->set_timing_function(element.property_transition_attributes(property_id)->timing_function);
auto key_frame_set = adopt_ref(*new Animations::KeyframeEffect::KeyFrameSet);
Animations::KeyframeEffect::KeyFrameSet::ResolvedKeyFrame initial_keyframe;
initial_keyframe.properties.set(property_id, m_start_value);
Animations::KeyframeEffect::KeyFrameSet::ResolvedKeyFrame final_keyframe;
final_keyframe.properties.set(property_id, m_end_value);
key_frame_set->keyframes_by_key.insert(0, initial_keyframe);
key_frame_set->keyframes_by_key.insert(100 * Animations::KeyframeEffect::AnimationKeyFrameKeyScaleFactor, final_keyframe);
m_keyframe_effect->set_key_frame_set(key_frame_set);
set_timeline(element.document().timeline());
set_owning_element(element);
set_effect(m_keyframe_effect);
element.associate_with_animation(*this);
element.set_transition(m_transition_property, *this);
HTML::TemporaryExecutionContext context(element.document().relevant_settings_object());
play().release_value_but_fixme_should_propagate_errors();
}
void CSSTransition::initialize(JS::Realm& realm)
@ -89,6 +134,25 @@ void CSSTransition::visit_edges(Cell::Visitor& visitor)
{
Base::visit_edges(visitor);
visitor.visit(m_cached_declaration);
visitor.visit(m_keyframe_effect);
}
double CSSTransition::timing_function_output_at_time(double t) const
{
auto progress = (t - transition_start_time()) / (transition_end_time() - transition_start_time());
// FIXME: Is this before_flag value correct?
bool before_flag = t < transition_start_time();
return m_keyframe_effect->timing_function().evaluate_at(progress, before_flag);
}
NonnullRefPtr<CSSStyleValue const> CSSTransition::value_at_time(double t) const
{
// https://drafts.csswg.org/css-transitions/#application
auto progress = timing_function_output_at_time(t);
auto result = interpolate_property(*m_keyframe_effect->target(), m_transition_property, m_start_value, m_end_value, progress);
if (result)
return result.release_nonnull();
return m_start_value;
}
}

45
Userland/Libraries/LibWeb/CSS/CSSTransition.h
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@ -1,5 +1,6 @@
/*
* Copyright (c) 2024, Matthew Olsson <mattco@serenityos.org>.
* Copyright (c) 2024, Matthew Olsson <mattco@serenityos.org>
* Copyright (c) 2024, Sam Atkins <sam@ladybird.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
@ -9,6 +10,7 @@
#include <LibWeb/Animations/Animation.h>
#include <LibWeb/CSS/CSSStyleValue.h>
#include <LibWeb/CSS/PropertyID.h>
#include <LibWeb/CSS/StyleValues/EasingStyleValue.h>
#include <LibWeb/CSS/Time.h>
namespace Web::CSS {
@ -18,18 +20,29 @@ class CSSTransition : public Animations::Animation {
JS_DECLARE_ALLOCATOR(CSSTransition);
public:
static JS::NonnullGCPtr<CSSTransition> create(JS::Realm&, PropertyID, size_t transition_generation);
static JS::NonnullGCPtr<CSSTransition> start_a_transition(DOM::Element&, PropertyID, size_t transition_generation,
double start_time, double end_time, NonnullRefPtr<CSSStyleValue const> start_value, NonnullRefPtr<CSSStyleValue const> end_value,
NonnullRefPtr<CSSStyleValue const> reversing_adjusted_start_value, double reversing_shortening_factor);
StringView transition_property() const { return string_from_property_id(m_transition_property); }
JS::GCPtr<CSS::CSSStyleDeclaration const> cached_declaration() const { return m_cached_declaration; }
void set_cached_declaration(JS::GCPtr<CSS::CSSStyleDeclaration const> declaration) { m_cached_declaration = declaration; }
virtual Animations::AnimationClass animation_class() const override;
virtual Optional<int> class_specific_composite_order(JS::NonnullGCPtr<Animations::Animation> other) const override;
double transition_start_time() const { return m_start_time; }
double transition_end_time() const { return m_end_time; }
NonnullRefPtr<CSSStyleValue const> transition_start_value() const { return m_start_value; }
NonnullRefPtr<CSSStyleValue const> transition_end_value() const { return m_end_value; }
NonnullRefPtr<CSSStyleValue const> reversing_adjusted_start_value() const { return m_reversing_adjusted_start_value; }
double reversing_shortening_factor() const { return m_reversing_shortening_factor; }
double timing_function_output_at_time(double t) const;
NonnullRefPtr<CSSStyleValue const> value_at_time(double t) const;
private:
CSSTransition(JS::Realm&, PropertyID, size_t transition_generation);
CSSTransition(JS::Realm&, DOM::Element&, PropertyID, size_t transition_generation,
double start_time, double end_time, NonnullRefPtr<CSSStyleValue const> start_value, NonnullRefPtr<CSSStyleValue const> end_value,
NonnullRefPtr<CSSStyleValue const> reversing_adjusted_start_value, double reversing_shortening_factor);
virtual void initialize(JS::Realm&) override;
virtual void visit_edges(Cell::Visitor&) override;
@ -41,6 +54,26 @@ private:
// https://drafts.csswg.org/css-transitions-2/#transition-generation
size_t m_transition_generation;
// https://drafts.csswg.org/css-transitions/#transition-start-time
double m_start_time;
// https://drafts.csswg.org/css-transitions/#transition-end-time
double m_end_time;
// https://drafts.csswg.org/css-transitions/#transition-start-value
NonnullRefPtr<CSS::CSSStyleValue const> m_start_value;
// https://drafts.csswg.org/css-transitions/#transition-end-value
NonnullRefPtr<CSS::CSSStyleValue const> m_end_value;
// https://drafts.csswg.org/css-transitions/#transition-reversing-adjusted-start-value
NonnullRefPtr<CSS::CSSStyleValue const> m_reversing_adjusted_start_value;
// https://drafts.csswg.org/css-transitions/#transition-reversing-shortening-factor
double m_reversing_shortening_factor;
JS::NonnullGCPtr<Animations::KeyframeEffect> m_keyframe_effect;
JS::GCPtr<CSS::CSSStyleDeclaration const> m_cached_declaration;
};

16
Userland/Libraries/LibWeb/CSS/Interpolation.cpp
View file

@ -72,6 +72,22 @@ ValueComparingRefPtr<CSSStyleValue const> interpolate_property(DOM::Element& ele
}
}
// https://drafts.csswg.org/css-transitions/#transitionable
bool property_values_are_transitionable(PropertyID property_id, CSSStyleValue const& old_value, CSSStyleValue const& new_value)
{
// When comparing the before-change style and after-change style for a given property,
// the property values are transitionable if they have an animation type that is neither not animatable nor discrete.
auto animation_type = animation_type_from_longhand_property(property_id);
if (animation_type == AnimationType::None || animation_type == AnimationType::Discrete)
return false;
// FIXME: Even when a property is transitionable, the two values may not be. The spec uses the example of inset/non-inset shadows.
(void)old_value;
(void)new_value;
return true;
}
// A null return value means the interpolated matrix was not invertible or otherwise invalid
RefPtr<CSSStyleValue const> interpolate_transform(DOM::Element& element, CSSStyleValue const& from, CSSStyleValue const& to, float delta)
{

3
Userland/Libraries/LibWeb/CSS/Interpolation.h
View file

@ -13,6 +13,9 @@ namespace Web::CSS {
ValueComparingRefPtr<CSSStyleValue const> interpolate_property(DOM::Element&, PropertyID, CSSStyleValue const& from, CSSStyleValue const& to, float delta);
// https://drafts.csswg.org/css-transitions/#transitionable
bool property_values_are_transitionable(PropertyID, CSSStyleValue const& old_value, CSSStyleValue const& new_value);
NonnullRefPtr<CSSStyleValue const> interpolate_value(DOM::Element&, CSSStyleValue const& from, CSSStyleValue const& to, float delta);
NonnullRefPtr<CSSStyleValue const> interpolate_box_shadow(DOM::Element&, CSSStyleValue const& from, CSSStyleValue const& to, float delta);
RefPtr<CSSStyleValue const> interpolate_transform(DOM::Element&, CSSStyleValue const& from, CSSStyleValue const& to, float delta);

201
Userland/Libraries/LibWeb/CSS/StyleComputer.cpp
View file

@ -32,6 +32,7 @@
#include <LibWeb/CSS/CSSLayerBlockRule.h>
#include <LibWeb/CSS/CSSLayerStatementRule.h>
#include <LibWeb/CSS/CSSStyleRule.h>
#include <LibWeb/CSS/CSSTransition.h>
#include <LibWeb/CSS/Interpolation.h>
#include <LibWeb/CSS/Parser/Parser.h>
#include <LibWeb/CSS/SelectorEngine.h>
@ -1294,6 +1295,198 @@ static void compute_transitioned_properties(StyleProperties const& style, DOM::E
}
}
// https://drafts.csswg.org/css-transitions/#starting
void StyleComputer::start_needed_transitions(StyleProperties const& previous_style, StyleProperties& new_style, DOM::Element& element, Optional<Selector::PseudoElement::Type> pseudo_element) const
{
// FIXME: Implement transitions for pseudo-elements
(void)pseudo_element;
// https://drafts.csswg.org/css-transitions/#transition-combined-duration
auto combined_duration = [](Animations::Animatable::TransitionAttributes const& transition_attributes) {
// Define the combined duration of the transition as the sum of max(matching transition duration, 0s) and the matching transition delay.
return max(transition_attributes.duration, 0) + transition_attributes.delay;
};
// For each element and property, the implementation must act as follows:
auto style_change_event_time = m_document->timeline()->current_time().value();
for (auto i = to_underlying(CSS::first_longhand_property_id); i <= to_underlying(CSS::last_longhand_property_id); ++i) {
auto property_id = static_cast<CSS::PropertyID>(i);
auto matching_transition_properties = element.property_transition_attributes(property_id);
auto before_change_value = previous_style.property(property_id, StyleProperties::WithAnimationsApplied::No);
auto after_change_value = new_style.property(property_id, StyleProperties::WithAnimationsApplied::No);
auto existing_transition = element.property_transition(property_id);
bool has_running_transition = existing_transition && !existing_transition->is_finished();
bool has_completed_transition = existing_transition && existing_transition->is_finished();
auto start_a_transition = [&](auto start_time, auto end_time, auto start_value, auto end_value, auto reversing_adjusted_start_value, auto reversing_shortening_factor) {
dbgln("Starting a transition of {} from {} to {}", string_from_property_id(property_id), start_value->to_string(), end_value->to_string());
auto transition = CSSTransition::start_a_transition(element, property_id, document().transition_generation(),
start_time, end_time, start_value, end_value, reversing_adjusted_start_value, reversing_shortening_factor);
// Immediately set the property's value to the transition's current value, to prevent single-frame jumps.
new_style.set_animated_property(property_id, transition->value_at_time(style_change_event_time));
};
// 1. If all of the following are true:
if (
// - the element does not have a running transition for the property,
(!has_running_transition) &&
// - the before-change style is different from the after-change style for that property, and the values for the property are transitionable,
(!before_change_value->equals(after_change_value) && property_values_are_transitionable(property_id, before_change_value, after_change_value)) &&
// - the element does not have a completed transition for the property
// or the end value of the completed transition is different from the after-change style for the property,
(!has_completed_transition || !existing_transition->transition_end_value()->equals(after_change_value)) &&
// - there is a matching transition-property value, and
(matching_transition_properties.has_value()) &&
// - the combined duration is greater than 0s,
(combined_duration(matching_transition_properties.value()) > 0)) {
dbgln("Transition step 1.");
// then implementations must remove the completed transition (if present) from the set of completed transitions
if (has_completed_transition)
element.remove_transition(property_id);
// and start a transition whose:
// - start time is the time of the style change event plus the matching transition delay,
auto start_time = style_change_event_time + matching_transition_properties->delay;
// - end time is the start time plus the matching transition duration,
auto end_time = start_time + matching_transition_properties->duration;
// - start value is the value of the transitioning property in the before-change style,
auto start_value = before_change_value;
// - end value is the value of the transitioning property in the after-change style,
auto end_value = after_change_value;
// - reversing-adjusted start value is the same as the start value, and
auto reversing_adjusted_start_value = start_value;
// - reversing shortening factor is 1.
double reversing_shortening_factor = 1;
start_a_transition(start_time, end_time, start_value, end_value, reversing_adjusted_start_value, reversing_shortening_factor);
}
// 2. Otherwise, if the element has a completed transition for the property
// and the end value of the completed transition is different from the after-change style for the property,
// then implementations must remove the completed transition from the set of completed transitions.
else if (has_completed_transition && !existing_transition->transition_end_value()->equals(after_change_value)) {
dbgln("Transition step 2.");
element.remove_transition(property_id);
}
// 3. If the element has a running transition or completed transition for the property,
// and there is not a matching transition-property value,
if (existing_transition && !matching_transition_properties.has_value()) {
// then implementations must cancel the running transition or remove the completed transition from the set of completed transitions.
dbgln("Transition step 3.");
if (has_running_transition)
existing_transition->cancel();
else
element.remove_transition(property_id);
}
// 4. If the element has a running transition for the property,
// there is a matching transition-property value,
// and the end value of the running transition is not equal to the value of the property in the after-change style, then:
if (has_running_transition && matching_transition_properties.has_value() && !existing_transition->transition_end_value()->equals(after_change_value)) {
dbgln("Transition step 4. existing end value = {}, after change value = {}", existing_transition->transition_end_value()->to_string(), after_change_value->to_string());
// 1. If the current value of the property in the running transition is equal to the value of the property in the after-change style,
// or if these two values are not transitionable,
// then implementations must cancel the running transition.
auto current_value = existing_transition->value_at_time(style_change_event_time);
if (current_value->equals(after_change_value) || !property_values_are_transitionable(property_id, current_value, after_change_value)) {
dbgln("Transition step 4.1");
existing_transition->cancel();
}
// 2. Otherwise, if the combined duration is less than or equal to 0s,
// or if the current value of the property in the running transition is not transitionable with the value of the property in the after-change style,
// then implementations must cancel the running transition.
else if ((combined_duration(matching_transition_properties.value()) <= 0)
|| !property_values_are_transitionable(property_id, current_value, after_change_value)) {
dbgln("Transition step 4.2");
existing_transition->cancel();
}
// 3. Otherwise, if the reversing-adjusted start value of the running transition is the same as the value of the property in the after-change style
// (see the section on reversing of transitions for why these case exists),
else if (existing_transition->reversing_adjusted_start_value()->equals(after_change_value)) {
dbgln("Transition step 4.3");
// implementations must cancel the running transition and start a new transition whose:
existing_transition->cancel();
// AD-HOC: Remove the cancelled transition, otherwise it breaks the invariant that there is only one
// running or completed transition for a property at once.
element.remove_transition(property_id);
// - reversing-adjusted start value is the end value of the running transition,
auto reversing_adjusted_start_value = existing_transition->transition_end_value();
// - reversing shortening factor is the absolute value, clamped to the range [0, 1], of the sum of:
// 1. the output of the timing function of the old transition at the time of the style change event,
// times the reversing shortening factor of the old transition
auto term_1 = existing_transition->timing_function_output_at_time(style_change_event_time) * existing_transition->reversing_shortening_factor();
// 2. 1 minus the reversing shortening factor of the old transition.
auto term_2 = 1 - existing_transition->reversing_shortening_factor();
double reversing_shortening_factor = clamp(abs(term_1 + term_2), 0.0, 1.0);
// - start time is the time of the style change event plus:
// 1. if the matching transition delay is nonnegative, the matching transition delay, or
// 2. if the matching transition delay is negative, the product of the new transition’s reversing shortening factor and the matching transition delay,
auto start_time = style_change_event_time
+ (matching_transition_properties->delay >= 0
? (matching_transition_properties->delay)
: (reversing_shortening_factor * matching_transition_properties->delay));
// - end time is the start time plus the product of the matching transition duration and the new transition’s reversing shortening factor,
auto end_time = start_time + (matching_transition_properties->duration * reversing_shortening_factor);
// - start value is the current value of the property in the running transition,
auto start_value = current_value;
// - end value is the value of the property in the after-change style,
auto end_value = after_change_value;
start_a_transition(start_time, end_time, start_value, end_value, reversing_adjusted_start_value, reversing_shortening_factor);
}
// 4. Otherwise,
else {
dbgln("Transition step 4.4");
// implementations must cancel the running transition and start a new transition whose:
existing_transition->cancel();
// AD-HOC: Remove the cancelled transition, otherwise it breaks the invariant that there is only one
// running or completed transition for a property at once.
element.remove_transition(property_id);
// - start time is the time of the style change event plus the matching transition delay,
auto start_time = style_change_event_time + matching_transition_properties->delay;
// - end time is the start time plus the matching transition duration,
auto end_time = start_time + matching_transition_properties->duration;
// - start value is the current value of the property in the running transition,
auto start_value = current_value;
// - end value is the value of the property in the after-change style,
auto end_value = after_change_value;
// - reversing-adjusted start value is the same as the start value, and
auto reversing_adjusted_start_value = start_value;
// - reversing shortening factor is 1.
double reversing_shortening_factor = 1;
start_a_transition(start_time, end_time, start_value, end_value, reversing_adjusted_start_value, reversing_shortening_factor);
}
}
}
}
// https://www.w3.org/TR/css-cascade/#cascading
// https://drafts.csswg.org/css-cascade-5/#layering
void StyleComputer::compute_cascaded_values(StyleProperties& style, DOM::Element& element, Optional<CSS::Selector::PseudoElement::Type> pseudo_element, bool& did_match_any_pseudo_element_rules, ComputeStyleMode mode) const
@ -1440,7 +1633,9 @@ void StyleComputer::compute_cascaded_values(StyleProperties& style, DOM::Element
// Important user agent declarations
cascade_declarations(style, element, pseudo_element, matching_rule_set.user_agent_rules, CascadeOrigin::UserAgent, Important::Yes);
// FIXME: Transition declarations [css-transitions-1]
// Transition declarations [css-transitions-1]
// Note that we have to do these after finishing computing the style,
// so they're not done here, but as the final step in compute_style_impl()
}
DOM::Element const* element_to_inherit_style_from(DOM::Element const* element, Optional<CSS::Selector::PseudoElement::Type> pseudo_element)
@ -2197,6 +2392,10 @@ RefPtr<StyleProperties> StyleComputer::compute_style_impl(DOM::Element& element,
// 9. Transition declarations [css-transitions-1]
// Theoretically this should be part of the cascade, but it works with computed values, which we don't have until now.
compute_transitioned_properties(style, element, pseudo_element);
if (auto const* previous_style = element.computed_css_values()) {
start_needed_transitions(*previous_style, style, element, pseudo_element);
}
return style;
}

1
Userland/Libraries/LibWeb/CSS/StyleComputer.h
View file

@ -174,6 +174,7 @@ private:
void compute_font(StyleProperties&, DOM::Element const*, Optional<CSS::Selector::PseudoElement::Type>) const;
void compute_math_depth(StyleProperties&, DOM::Element const*, Optional<CSS::Selector::PseudoElement::Type>) const;
void compute_defaulted_values(StyleProperties&, DOM::Element const*, Optional<CSS::Selector::PseudoElement::Type>) const;
void start_needed_transitions(StyleProperties const& old_style, StyleProperties& new_style, DOM::Element&, Optional<Selector::PseudoElement::Type>) const;
void absolutize_values(StyleProperties&) const;
void resolve_effective_overflow_values(StyleProperties&) const;
void transform_box_type_if_needed(StyleProperties&, DOM::Element const&, Optional<CSS::Selector::PseudoElement::Type>) const;