ladybird/Userland/Libraries/LibWeb/Layout/InlineLevelIterator.h
Andreas Kling 1cea4e6407 LibWeb: Use cached UsedValues pointer in IFC and its helper classes
This avoids expensive LayoutState lookups when we already have the
pointer sitting around anyway.
2024-03-16 14:27:59 +01:00

106 lines
3.4 KiB
C++

/*
* Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Noncopyable.h>
#include <LibWeb/Layout/BlockContainer.h>
#include <LibWeb/Layout/InlineNode.h>
#include <LibWeb/Layout/LayoutState.h>
#include <LibWeb/Layout/TextNode.h>
namespace Web::Layout {
// This class iterates over all the inline-level objects within an inline formatting context.
// By repeatedly calling next() with the remaining available width on the current line,
// it returns an "Item" representing the next piece of inline-level content to be placed on the line.
class InlineLevelIterator {
AK_MAKE_NONCOPYABLE(InlineLevelIterator);
AK_MAKE_NONMOVABLE(InlineLevelIterator);
public:
struct Item {
enum class Type {
Text,
Element,
ForcedBreak,
AbsolutelyPositionedElement,
FloatingElement,
};
Type type {};
JS::GCPtr<Layout::Node const> node {};
Vector<Gfx::DrawGlyphOrEmoji> glyph_run {};
size_t offset_in_node { 0 };
size_t length_in_node { 0 };
CSSPixels width { 0.0f };
CSSPixels padding_start { 0.0f };
CSSPixels padding_end { 0.0f };
CSSPixels border_start { 0.0f };
CSSPixels border_end { 0.0f };
CSSPixels margin_start { 0.0f };
CSSPixels margin_end { 0.0f };
bool is_collapsible_whitespace { false };
CSSPixels border_box_width() const
{
return border_start + padding_start + width + padding_end + border_end;
}
};
InlineLevelIterator(Layout::InlineFormattingContext&, LayoutState&, Layout::BlockContainer const& containing_block, LayoutState::UsedValues const& containing_block_used_values, LayoutMode);
Optional<Item> next();
CSSPixels next_non_whitespace_sequence_width();
private:
Optional<Item> next_without_lookahead();
void skip_to_next();
void compute_next();
void enter_text_node(Layout::TextNode const&);
void enter_node_with_box_model_metrics(Layout::NodeWithStyleAndBoxModelMetrics const&);
void exit_node_with_box_model_metrics();
void add_extra_box_model_metrics_to_item(Item&, bool add_leading_metrics, bool add_trailing_metrics);
Layout::Node const* next_inline_node_in_pre_order(Layout::Node const& current, Layout::Node const* stay_within);
Layout::InlineFormattingContext& m_inline_formatting_context;
Layout::LayoutState& m_layout_state;
JS::NonnullGCPtr<BlockContainer const> m_containing_block;
LayoutState::UsedValues const& m_containing_block_used_values;
JS::GCPtr<Layout::Node const> m_current_node;
JS::GCPtr<Layout::Node const> m_next_node;
LayoutMode const m_layout_mode;
struct TextNodeContext {
bool do_collapse {};
bool do_wrap_lines {};
bool do_respect_linebreaks {};
bool is_first_chunk {};
bool is_last_chunk {};
TextNode::ChunkIterator chunk_iterator;
Optional<TextNode::Chunk> next_chunk {};
};
Optional<TextNodeContext> m_text_node_context;
struct ExtraBoxMetrics {
CSSPixels margin { 0 };
CSSPixels border { 0 };
CSSPixels padding { 0 };
};
Optional<ExtraBoxMetrics> m_extra_leading_metrics;
Optional<ExtraBoxMetrics> m_extra_trailing_metrics;
Vector<JS::NonnullGCPtr<NodeWithStyleAndBoxModelMetrics const>> m_box_model_node_stack;
Queue<InlineLevelIterator::Item> m_lookahead_items;
};
}