ladybird/Libraries/LibWeb/Layout/Box.cpp
Aliaksandr Kalenik 7cae4fadbc LibWeb: Cache "has size containment" flag in Layout::Box
Allows us to avoid DOM node lookup whenever we need to query natural
size of a box during layout.

Makes 3-4% of `Box::preferred_aspect_ratio()` go away from profiles on
www.nyan.cat
2025-03-26 17:52:02 +00:00

96 lines
2.8 KiB
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <andreas@ladybird.org>
* Copyright (c) 2021-2022, Sam Atkins <atkinssj@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibWeb/DOM/Document.h>
#include <LibWeb/HTML/HTMLHtmlElement.h>
#include <LibWeb/Layout/BlockContainer.h>
#include <LibWeb/Layout/Box.h>
#include <LibWeb/Layout/FormattingContext.h>
#include <LibWeb/Painting/PaintableBox.h>
namespace Web::Layout {
Box::Box(DOM::Document& document, DOM::Node* node, GC::Ref<CSS::ComputedProperties> style)
: NodeWithStyleAndBoxModelMetrics(document, node, move(style))
{
}
Box::Box(DOM::Document& document, DOM::Node* node, NonnullOwnPtr<CSS::ComputedValues> computed_values)
: NodeWithStyleAndBoxModelMetrics(document, node, move(computed_values))
{
}
Box::~Box()
{
}
Optional<CSSPixels> Box::natural_width() const
{
// https://drafts.csswg.org/css-contain-2/#containment-size
// Replaced elements must be treated as having a natural width and height of 0 and no natural aspect
// ratio.
if (m_has_size_containment)
return 0;
return m_natural_width;
}
Optional<CSSPixels> Box::natural_height() const
{
// https://drafts.csswg.org/css-contain-2/#containment-size
// Replaced elements must be treated as having a natural width and height of 0 and no natural aspect
// ratio.
if (m_has_size_containment)
return 0;
return m_natural_height;
}
Optional<CSSPixelFraction> Box::natural_aspect_ratio() const
{
// https://drafts.csswg.org/css-contain-2/#containment-size
// Replaced elements must be treated as having a natural width and height of 0 and no natural aspect
// ratio.
if (m_has_size_containment)
return {};
return m_natural_aspect_ratio;
}
void Box::visit_edges(Cell::Visitor& visitor)
{
Base::visit_edges(visitor);
visitor.visit(m_contained_abspos_children);
}
GC::Ptr<Painting::Paintable> Box::create_paintable() const
{
return Painting::PaintableBox::create(*this);
}
Painting::PaintableBox* Box::paintable_box()
{
return static_cast<Painting::PaintableBox*>(Node::first_paintable());
}
Painting::PaintableBox const* Box::paintable_box() const
{
return static_cast<Painting::PaintableBox const*>(Node::first_paintable());
}
Optional<CSSPixelFraction> Box::preferred_aspect_ratio() const
{
auto computed_aspect_ratio = computed_values().aspect_ratio();
if (computed_aspect_ratio.use_natural_aspect_ratio_if_available && natural_aspect_ratio().has_value())
return natural_aspect_ratio();
if (!computed_aspect_ratio.preferred_ratio.has_value())
return {};
auto ratio = computed_aspect_ratio.preferred_ratio.release_value();
if (ratio.is_degenerate())
return {};
return CSSPixelFraction(ratio.numerator(), ratio.denominator());
}
}