ladybird/Userland/Libraries/LibWeb/Layout/BlockFormattingContext.h
Andreas Kling c1f0d21bbe LibWeb: Rename the LayoutMode enum values and explain them
The old mode names, while mechanically accurate, didn't really reflect
their relationship to the CSS specifications.

This patch renames them as follows:

    Default => Normal
    AllPossibleLineBreaks => MinContent
    OnlyRequiredLineBreaks => MaxContent

There's also now an explainer comment with the LayoutMode enum about the
specific implications of layout in each mode.
2022-03-19 15:46:15 +01:00

115 lines
3.6 KiB
C++

/*
* Copyright (c) 2020-2022, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Vector.h>
#include <LibWeb/Forward.h>
#include <LibWeb/Layout/BlockContainer.h>
#include <LibWeb/Layout/FormattingContext.h>
namespace Web::Layout {
// https://www.w3.org/TR/css-display/#block-formatting-context
class BlockFormattingContext : public FormattingContext {
public:
explicit BlockFormattingContext(FormattingState&, BlockContainer const&, FormattingContext* parent);
~BlockFormattingContext();
virtual void run(Box const&, LayoutMode) override;
bool is_initial() const;
auto const& left_side_floats() const { return m_left_floats; }
auto const& right_side_floats() const { return m_right_floats; }
static float compute_theoretical_height(FormattingState const&, Box const&);
void compute_width(Box const&, LayoutMode = LayoutMode::Normal);
// https://www.w3.org/TR/css-display/#block-formatting-context-root
BlockContainer const& root() const { return static_cast<BlockContainer const&>(context_box()); }
virtual void parent_context_did_dimension_child_root_box() override;
static void compute_height(Box const&, FormattingState&);
void add_absolutely_positioned_box(Box const& box) { m_absolutely_positioned_boxes.append(box); }
SpaceUsedByFloats space_used_by_floats(float y) const;
virtual float greatest_child_width(Box const&) override;
private:
virtual bool is_block_formatting_context() const final { return true; }
void compute_width_for_floating_box(Box const&, LayoutMode);
void compute_width_for_block_level_replaced_element_in_normal_flow(ReplacedBox const&);
void layout_initial_containing_block(LayoutMode);
void layout_block_level_children(BlockContainer const&, LayoutMode);
void layout_inline_children(BlockContainer const&, LayoutMode);
void compute_vertical_box_model_metrics(Box const& box, BlockContainer const& containing_block);
void place_block_level_element_in_normal_flow_horizontally(Box const& child_box, BlockContainer const&);
void place_block_level_element_in_normal_flow_vertically(Box const& child_box, BlockContainer const&);
void layout_floating_box(Box const& child, BlockContainer const& containing_block, LayoutMode);
void layout_list_item_marker(ListItemBox const&);
enum class FloatSide {
Left,
Right,
};
struct FloatingBox {
Box const& box;
// Offset from left/right edge to the left content edge of `box`.
float offset_from_edge { 0 };
// Top margin edge of `box`.
float top_margin_edge { 0 };
// Bottom margin edge of `box`.
float bottom_margin_edge { 0 };
};
struct FloatSideData {
// Floating boxes currently accumulating on this side.
Vector<FloatingBox&> current_boxes;
// Combined width of boxes currently accumulating on this side.
// This is the innermost margin of the innermost floating box.
float current_width { 0 };
// Highest value of `m_current_width` we've seen.
float max_width { 0 };
// All floating boxes encountered thus far within this BFC.
Vector<NonnullOwnPtr<FloatingBox>> all_boxes;
// Current Y offset from BFC root top.
float y_offset { 0 };
void clear()
{
current_boxes.clear();
current_width = 0;
}
};
FloatSideData m_left_floats;
FloatSideData m_right_floats;
Vector<Box const&> m_absolutely_positioned_boxes;
bool m_was_notified_after_parent_dimensioned_my_root_box { false };
};
}