mirror of
https://github.com/LadybirdBrowser/ladybird.git
synced 2025-10-23 00:19:18 +00:00
6452bfb612
This way we don't have to allocate separate vector with both scroll and sticky frame that is used for display list player (scroll and sticky frames share id pool), so player could access offset by frame id. No behavior change.
54 lines
1.5 KiB
C++
54 lines
1.5 KiB
C++
/*
|
|
* Copyright (c) 2024, Aliaksandr Kalenik <kalenik.aliaksandr@gmail.com>
|
|
*
|
|
* SPDX-License-Identifier: BSD-2-Clause
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include <LibWeb/Forward.h>
|
|
#include <LibWeb/PixelUnits.h>
|
|
|
|
namespace Web::Painting {
|
|
|
|
class ScrollFrame : public RefCounted<ScrollFrame> {
|
|
public:
|
|
ScrollFrame(PaintableBox const& paintable_box, size_t id, bool sticky, RefPtr<ScrollFrame const> parent);
|
|
|
|
PaintableBox const& paintable_box() const { return *m_paintable_box; }
|
|
|
|
size_t id() const { return m_id; }
|
|
|
|
bool is_sticky() const { return m_sticky; }
|
|
|
|
CSSPixelPoint cumulative_offset() const
|
|
{
|
|
if (!m_cached_cumulative_offset.has_value()) {
|
|
m_cached_cumulative_offset = m_own_offset;
|
|
if (m_parent) {
|
|
m_cached_cumulative_offset.value() += m_parent->cumulative_offset();
|
|
}
|
|
}
|
|
return m_cached_cumulative_offset.value();
|
|
}
|
|
|
|
CSSPixelPoint own_offset() const { return m_own_offset; }
|
|
void set_own_offset(CSSPixelPoint offset)
|
|
{
|
|
m_cached_cumulative_offset.clear();
|
|
m_own_offset = offset;
|
|
}
|
|
|
|
private:
|
|
WeakPtr<PaintableBox> m_paintable_box;
|
|
size_t m_id { 0 };
|
|
bool m_sticky { false };
|
|
RefPtr<ScrollFrame const> m_parent;
|
|
CSSPixelPoint m_own_offset;
|
|
|
|
// Caching here relies on the fact that offsets of all scroll frames are invalidated when any of them changes,
|
|
// so we don't need to worry about invalidating the cache when the parent's offset changes.
|
|
mutable Optional<CSSPixelPoint> m_cached_cumulative_offset;
|
|
};
|
|
|
|
}
|