4f08fcde29
At one point in the past, we had some functions that were called across different formatting context types, which necessitated making them static and taking the LayoutState as a parameter. In all cases, those functions were used to do incorrect hacks, all of which we've replaced with more correct solutions. :^)
1169 lines
58 KiB
C++
1169 lines
58 KiB
C++
/*
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* Copyright (c) 2020-2022, Andreas Kling <kling@serenityos.org>
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*
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* SPDX-License-Identifier: BSD-2-Clause
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*/
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#include <AK/TemporaryChange.h>
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#include <LibWeb/CSS/Length.h>
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#include <LibWeb/DOM/Node.h>
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#include <LibWeb/Dump.h>
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#include <LibWeb/HTML/BrowsingContext.h>
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#include <LibWeb/Layout/BlockContainer.h>
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#include <LibWeb/Layout/BlockFormattingContext.h>
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#include <LibWeb/Layout/Box.h>
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#include <LibWeb/Layout/InlineFormattingContext.h>
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#include <LibWeb/Layout/LineBuilder.h>
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#include <LibWeb/Layout/ListItemBox.h>
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#include <LibWeb/Layout/ListItemMarkerBox.h>
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#include <LibWeb/Layout/ReplacedBox.h>
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#include <LibWeb/Layout/SVGSVGBox.h>
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#include <LibWeb/Layout/TableWrapper.h>
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#include <LibWeb/Layout/Viewport.h>
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namespace Web::Layout {
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BlockFormattingContext::BlockFormattingContext(LayoutState& state, BlockContainer const& root, FormattingContext* parent)
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: FormattingContext(Type::Block, state, root, parent)
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{
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}
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BlockFormattingContext::~BlockFormattingContext()
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{
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if (!m_was_notified_after_parent_dimensioned_my_root_box) {
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// HACK: The parent formatting context never notified us after assigning dimensions to our root box.
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// Pretend that it did anyway, to make sure absolutely positioned children get laid out.
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// FIXME: Get rid of this hack once parent contexts behave properly.
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parent_context_did_dimension_child_root_box();
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}
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}
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CSSPixels BlockFormattingContext::automatic_content_width() const
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{
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return greatest_child_width(root());
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}
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CSSPixels BlockFormattingContext::automatic_content_height() const
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{
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return compute_auto_height_for_block_formatting_context_root(root());
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}
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static bool margins_collapse_through(Box const& box, LayoutState& state)
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{
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// FIXME: A box's own margins collapse if the 'min-height' property is zero, and it has neither top or bottom borders
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// nor top or bottom padding, and it has a 'height' of either 0 or 'auto', and it does not contain a line box, and
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// all of its in-flow children's margins (if any) collapse.
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// https://www.w3.org/TR/CSS22/box.html#collapsing-margins
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return state.get(box).border_box_height() == 0;
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}
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void BlockFormattingContext::run(Box const&, LayoutMode layout_mode, AvailableSpace const& available_space)
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{
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if (is<Viewport>(root())) {
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layout_viewport(layout_mode, available_space);
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return;
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}
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if (root().children_are_inline())
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layout_inline_children(root(), layout_mode, available_space);
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else
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layout_block_level_children(root(), layout_mode, available_space);
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// Assign collapsed margin left after children layout of formatting context to the last child box
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if (m_margin_state.current_collapsed_margin() != 0) {
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for (auto* child_box = root().last_child_of_type<Box>(); child_box; child_box = child_box->previous_sibling_of_type<Box>()) {
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if (child_box->is_absolutely_positioned() || child_box->is_floating())
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continue;
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if (margins_collapse_through(*child_box, m_state))
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continue;
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m_state.get_mutable(*child_box).margin_bottom = m_margin_state.current_collapsed_margin().value();
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break;
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}
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}
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}
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void BlockFormattingContext::parent_context_did_dimension_child_root_box()
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{
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m_was_notified_after_parent_dimensioned_my_root_box = true;
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// Left-side floats: offset_from_edge is from left edge (0) to left content edge of floating_box.
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for (auto& floating_box : m_left_floats.all_boxes) {
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auto& box_state = m_state.get_mutable(floating_box->box);
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box_state.set_content_x(floating_box->offset_from_edge.value());
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}
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// Right-side floats: offset_from_edge is from right edge (float_containing_block_width) to the left content edge of floating_box.
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for (auto& floating_box : m_right_floats.all_boxes) {
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auto float_containing_block_width = containing_block_width_for(floating_box->box);
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auto& box_state = m_state.get_mutable(floating_box->box);
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box_state.set_content_x((float_containing_block_width - floating_box->offset_from_edge).value());
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}
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// We can also layout absolutely positioned boxes within this BFC.
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for (auto& box : m_absolutely_positioned_boxes) {
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auto& cb_state = m_state.get(*box->containing_block());
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auto available_width = AvailableSize::make_definite(cb_state.content_width() + cb_state.padding_left + cb_state.padding_right);
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auto available_height = AvailableSize::make_definite(cb_state.content_height() + cb_state.padding_top + cb_state.padding_bottom);
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layout_absolutely_positioned_element(box, AvailableSpace(available_width, available_height));
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}
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}
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void BlockFormattingContext::compute_width(Box const& box, AvailableSpace const& available_space, LayoutMode)
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{
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if (box.is_absolutely_positioned()) {
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compute_width_for_absolutely_positioned_element(box, available_space);
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return;
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}
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auto remaining_available_space = available_space;
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if (available_space.width.is_definite() && creates_block_formatting_context(box)) {
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// 9.5 Floats
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// The border box of a table, a block-level replaced element, or an element in the normal flow that establishes a
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// new block formatting context (such as an element with 'overflow' other than 'visible') must not overlap the margin
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// box of any floats in the same block formatting context as the element itself. If necessary, implementations should
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// clear the said element by placing it below any preceding floats, but may place it adjacent to such floats if there is
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// sufficient space. They may even make the border box of said element narrower than defined by section 10.3.3.
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// CSS2 does not define when a UA may put said element next to the float or by how much said element may
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// become narrower.
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auto intrusion = intrusion_by_floats_into_box(box, 0);
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auto remaining_width = available_space.width.to_px() - intrusion.left - intrusion.right;
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remaining_available_space.width = AvailableSize::make_definite(remaining_width);
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}
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if (is<ReplacedBox>(box)) {
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// FIXME: This should not be done *by* ReplacedBox
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auto& replaced = verify_cast<ReplacedBox>(box);
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// FIXME: This const_cast is gross.
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const_cast<ReplacedBox&>(replaced).prepare_for_replaced_layout();
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compute_width_for_block_level_replaced_element_in_normal_flow(replaced, remaining_available_space);
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if (box.is_floating()) {
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// 10.3.6 Floating, replaced elements:
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// https://www.w3.org/TR/CSS22/visudet.html#float-replaced-width
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return;
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}
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}
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if (box.is_floating()) {
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// 10.3.5 Floating, non-replaced elements:
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// https://www.w3.org/TR/CSS22/visudet.html#float-width
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compute_width_for_floating_box(box, available_space);
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return;
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}
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auto const& computed_values = box.computed_values();
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auto width_of_containing_block = remaining_available_space.width.to_px();
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auto width_of_containing_block_as_length_for_resolve = remaining_available_space.width.is_definite() ? CSS::Length::make_px(width_of_containing_block) : CSS::Length::make_px(0);
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auto zero_value = CSS::Length::make_px(0);
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auto margin_left = CSS::Length::make_auto();
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auto margin_right = CSS::Length::make_auto();
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auto const padding_left = computed_values.padding().left().to_px(box, width_of_containing_block);
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auto const padding_right = computed_values.padding().right().to_px(box, width_of_containing_block);
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auto& box_state = m_state.get_mutable(box);
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box_state.border_left = computed_values.border_left().width;
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box_state.border_right = computed_values.border_right().width;
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box_state.padding_left = padding_left;
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box_state.padding_right = padding_right;
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// NOTE: If we are calculating the min-content or max-content width of this box,
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// and the width should be treated as auto, then we can simply return here,
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// as the preferred width and min/max constraints are irrelevant for intrinsic sizing.
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if (box_state.width_constraint != SizeConstraint::None)
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return;
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auto try_compute_width = [&](auto const& a_width) {
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CSS::Length width = a_width;
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margin_left = computed_values.margin().left().resolved(box, width_of_containing_block_as_length_for_resolve);
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margin_right = computed_values.margin().right().resolved(box, width_of_containing_block_as_length_for_resolve);
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CSSPixels total_px = computed_values.border_left().width + computed_values.border_right().width;
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for (auto& value : { margin_left, CSS::Length::make_px(padding_left), width, CSS::Length::make_px(padding_right), margin_right }) {
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total_px += value.to_px(box);
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}
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if (!box.is_inline()) {
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// 10.3.3 Block-level, non-replaced elements in normal flow
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// If 'width' is not 'auto' and 'border-left-width' + 'padding-left' + 'width' + 'padding-right' + 'border-right-width' (plus any of 'margin-left' or 'margin-right' that are not 'auto') is larger than the width of the containing block, then any 'auto' values for 'margin-left' or 'margin-right' are, for the following rules, treated as zero.
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if (!width.is_auto() && total_px > width_of_containing_block) {
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if (margin_left.is_auto())
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margin_left = zero_value;
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if (margin_right.is_auto())
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margin_right = zero_value;
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}
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// 10.3.3 cont'd.
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auto underflow_px = width_of_containing_block - total_px;
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if (available_space.width.is_intrinsic_sizing_constraint())
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underflow_px = 0;
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if (width.is_auto()) {
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if (margin_left.is_auto())
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margin_left = zero_value;
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if (margin_right.is_auto())
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margin_right = zero_value;
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if (available_space.width.is_definite()) {
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if (underflow_px >= 0) {
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width = CSS::Length::make_px(underflow_px);
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} else {
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width = zero_value;
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margin_right = CSS::Length::make_px(margin_right.to_px(box) + underflow_px.value());
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}
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}
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} else {
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if (!margin_left.is_auto() && !margin_right.is_auto()) {
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margin_right = CSS::Length::make_px(margin_right.to_px(box) + underflow_px.value());
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} else if (!margin_left.is_auto() && margin_right.is_auto()) {
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margin_right = CSS::Length::make_px(underflow_px);
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} else if (margin_left.is_auto() && !margin_right.is_auto()) {
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margin_left = CSS::Length::make_px(underflow_px);
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} else { // margin_left.is_auto() && margin_right.is_auto()
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auto half_of_the_underflow = CSS::Length::make_px(underflow_px / 2);
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margin_left = half_of_the_underflow;
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margin_right = half_of_the_underflow;
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}
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}
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}
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return width;
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};
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auto input_width = [&] {
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if (is<ReplacedBox>(box)) {
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// NOTE: Replaced elements had their width calculated independently above.
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// We use that width as the input here to ensure that margins get resolved.
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return CSS::Length::make_px(box_state.content_width());
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}
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if (is<TableWrapper>(box))
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return CSS::Length::make_px(compute_table_box_width_inside_table_wrapper(box, remaining_available_space));
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if (should_treat_width_as_auto(box, remaining_available_space))
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return CSS::Length::make_auto();
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return calculate_inner_width(box, remaining_available_space.width, computed_values.width());
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}();
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// 1. The tentative used width is calculated (without 'min-width' and 'max-width')
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auto used_width = try_compute_width(input_width);
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// 2. The tentative used width is greater than 'max-width', the rules above are applied again,
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// but this time using the computed value of 'max-width' as the computed value for 'width'.
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if (!computed_values.max_width().is_none()) {
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auto max_width = calculate_inner_width(box, remaining_available_space.width, computed_values.max_width());
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auto used_width_px = used_width.is_auto() ? remaining_available_space.width.to_px() : used_width.to_px(box);
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if (used_width_px > max_width.to_px(box)) {
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used_width = try_compute_width(max_width);
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}
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}
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// 3. If the resulting width is smaller than 'min-width', the rules above are applied again,
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// but this time using the value of 'min-width' as the computed value for 'width'.
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if (!computed_values.min_width().is_auto()) {
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auto min_width = calculate_inner_width(box, remaining_available_space.width, computed_values.min_width());
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auto used_width_px = used_width.is_auto() ? remaining_available_space.width.to_px() : used_width.to_px(box);
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if (used_width_px < min_width.to_px(box)) {
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used_width = try_compute_width(min_width);
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}
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}
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if (!is<ReplacedBox>(box) && !used_width.is_auto())
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box_state.set_content_width(used_width.to_px(box));
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box_state.margin_left = margin_left.to_px(box);
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box_state.margin_right = margin_right.to_px(box);
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}
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void BlockFormattingContext::compute_width_for_floating_box(Box const& box, AvailableSpace const& available_space)
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{
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// 10.3.5 Floating, non-replaced elements
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auto& computed_values = box.computed_values();
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auto zero_value = CSS::Length::make_px(0);
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auto width_of_containing_block = available_space.width.to_px();
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auto width_of_containing_block_as_length_for_resolve = CSS::Length::make_px(width_of_containing_block);
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if (!available_space.width.is_definite())
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width_of_containing_block_as_length_for_resolve = CSS::Length::make_px(0);
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auto margin_left = computed_values.margin().left().resolved(box, width_of_containing_block_as_length_for_resolve);
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auto margin_right = computed_values.margin().right().resolved(box, width_of_containing_block_as_length_for_resolve);
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auto const padding_left = computed_values.padding().left().to_px(box, width_of_containing_block);
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auto const padding_right = computed_values.padding().right().to_px(box, width_of_containing_block);
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// If 'margin-left', or 'margin-right' are computed as 'auto', their used value is '0'.
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if (margin_left.is_auto())
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margin_left = zero_value;
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if (margin_right.is_auto())
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margin_right = zero_value;
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auto compute_width = [&](auto width) {
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// If 'width' is computed as 'auto', the used value is the "shrink-to-fit" width.
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if (width.is_auto()) {
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// Find the available width: in this case, this is the width of the containing
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// block minus the used values of 'margin-left', 'border-left-width', 'padding-left',
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// 'padding-right', 'border-right-width', 'margin-right', and the widths of any relevant scroll bars.
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auto available_width = width_of_containing_block
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- margin_left.to_px(box) - computed_values.border_left().width - padding_left
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- padding_right - computed_values.border_right().width - margin_right.to_px(box);
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auto result = calculate_shrink_to_fit_widths(box);
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// Then the shrink-to-fit width is: min(max(preferred minimum width, available width), preferred width).
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width = CSS::Length::make_px(min(max(result.preferred_minimum_width, available_width), result.preferred_width));
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}
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return width;
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};
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auto input_width = [&] {
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if (should_treat_width_as_auto(box, available_space))
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return CSS::Length::make_auto();
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return calculate_inner_width(box, available_space.width, computed_values.width());
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}();
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// 1. The tentative used width is calculated (without 'min-width' and 'max-width')
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auto width = compute_width(input_width);
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// 2. The tentative used width is greater than 'max-width', the rules above are applied again,
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// but this time using the computed value of 'max-width' as the computed value for 'width'.
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if (!computed_values.max_width().is_none()) {
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auto max_width = calculate_inner_width(box, available_space.width, computed_values.max_width());
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if (width.to_px(box) > max_width.to_px(box))
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width = compute_width(max_width);
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}
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// 3. If the resulting width is smaller than 'min-width', the rules above are applied again,
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// but this time using the value of 'min-width' as the computed value for 'width'.
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if (!computed_values.min_width().is_auto()) {
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auto min_width = calculate_inner_width(box, available_space.width, computed_values.min_width());
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if (width.to_px(box) < min_width.to_px(box))
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width = compute_width(min_width);
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}
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auto& box_state = m_state.get_mutable(box);
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box_state.set_content_width(width.to_px(box));
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box_state.margin_left = margin_left.to_px(box);
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box_state.margin_right = margin_right.to_px(box);
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box_state.border_left = computed_values.border_left().width;
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box_state.border_right = computed_values.border_right().width;
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box_state.padding_left = padding_left;
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box_state.padding_right = padding_right;
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}
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void BlockFormattingContext::compute_width_for_block_level_replaced_element_in_normal_flow(ReplacedBox const& box, AvailableSpace const& available_space)
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{
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// 10.3.6 Floating, replaced elements
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auto& computed_values = box.computed_values();
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auto zero_value = CSS::Length::make_px(0);
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auto width_of_containing_block = available_space.width.to_px();
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auto width_of_containing_block_as_length_for_resolve = CSS::Length::make_px(width_of_containing_block);
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if (!available_space.width.is_definite())
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width_of_containing_block_as_length_for_resolve = CSS::Length::make_px(0);
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// 10.3.4 Block-level, replaced elements in normal flow
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// The used value of 'width' is determined as for inline replaced elements. Then the rules for
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// non-replaced block-level elements are applied to determine the margins.
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auto margin_left = computed_values.margin().left().resolved(box, width_of_containing_block_as_length_for_resolve);
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auto margin_right = computed_values.margin().right().resolved(box, width_of_containing_block_as_length_for_resolve);
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auto const padding_left = computed_values.padding().left().to_px(box, width_of_containing_block);
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auto const padding_right = computed_values.padding().right().to_px(box, width_of_containing_block);
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// If 'margin-left', or 'margin-right' are computed as 'auto', their used value is '0'.
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if (margin_left.is_auto())
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margin_left = zero_value;
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if (margin_right.is_auto())
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margin_right = zero_value;
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auto& box_state = m_state.get_mutable(box);
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box_state.set_content_width(compute_width_for_replaced_element(box, available_space));
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box_state.margin_left = margin_left.to_px(box);
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box_state.margin_right = margin_right.to_px(box);
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box_state.border_left = computed_values.border_left().width;
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box_state.border_right = computed_values.border_right().width;
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box_state.padding_left = padding_left;
|
||
box_state.padding_right = padding_right;
|
||
}
|
||
|
||
CSSPixels BlockFormattingContext::compute_table_box_width_inside_table_wrapper(Box const& box, AvailableSpace const& available_space)
|
||
{
|
||
// 17.5.2
|
||
// Table wrapper width should be equal to width of table box it contains
|
||
|
||
auto const& computed_values = box.computed_values();
|
||
|
||
auto width_of_containing_block = available_space.width.to_px();
|
||
auto width_of_containing_block_as_length_for_resolve = available_space.width.is_definite() ? CSS::Length::make_px(width_of_containing_block) : CSS::Length::make_px(0);
|
||
|
||
auto zero_value = CSS::Length::make_px(0);
|
||
|
||
auto margin_left = computed_values.margin().left().resolved(box, width_of_containing_block_as_length_for_resolve);
|
||
auto margin_right = computed_values.margin().right().resolved(box, width_of_containing_block_as_length_for_resolve);
|
||
|
||
// If 'margin-left', or 'margin-right' are computed as 'auto', their used value is '0'.
|
||
if (margin_left.is_auto())
|
||
margin_left = zero_value;
|
||
if (margin_right.is_auto())
|
||
margin_right = zero_value;
|
||
|
||
// table-wrapper can't have borders or paddings but it might have margin taken from table-root.
|
||
auto available_width = width_of_containing_block - margin_left.to_px(box) - margin_right.to_px(box);
|
||
|
||
LayoutState throwaway_state(&m_state);
|
||
throwaway_state.get_mutable(box).set_content_width(available_width);
|
||
auto context = create_independent_formatting_context_if_needed(throwaway_state, box);
|
||
VERIFY(context);
|
||
context->run(box, LayoutMode::IntrinsicSizing, m_state.get(box).available_inner_space_or_constraints_from(available_space));
|
||
|
||
Optional<Box const&> table_box;
|
||
box.for_each_in_subtree_of_type<Box>([&](Box const& child_box) {
|
||
if (child_box.display().is_table_inside()) {
|
||
table_box = child_box;
|
||
return IterationDecision::Break;
|
||
}
|
||
return IterationDecision::Continue;
|
||
});
|
||
VERIFY(table_box.has_value());
|
||
|
||
auto table_used_width = throwaway_state.get(*table_box).content_width();
|
||
return table_used_width > available_width ? available_width : table_used_width;
|
||
}
|
||
|
||
void BlockFormattingContext::compute_height(Box const& box, AvailableSpace const& available_space)
|
||
{
|
||
auto const& computed_values = box.computed_values();
|
||
auto containing_block_height = CSS::Length::make_px(available_space.height.to_px());
|
||
|
||
// Then work out what the height is, based on box type and CSS properties.
|
||
CSSPixels height = 0;
|
||
if (is<ReplacedBox>(box)) {
|
||
height = compute_height_for_replaced_element(verify_cast<ReplacedBox>(box), available_space);
|
||
} else {
|
||
if (should_treat_height_as_auto(box, available_space)) {
|
||
height = compute_auto_height_for_block_level_element(box, m_state.get(box).available_inner_space_or_constraints_from(available_space));
|
||
} else {
|
||
height = calculate_inner_height(box, available_space.height, computed_values.height()).to_px(box);
|
||
}
|
||
}
|
||
|
||
if (!computed_values.max_height().is_none()) {
|
||
auto max_height = calculate_inner_height(box, available_space.height, computed_values.max_height());
|
||
if (!max_height.is_auto())
|
||
height = min(height, max_height.to_px(box));
|
||
}
|
||
if (!computed_values.min_height().is_auto()) {
|
||
height = max(height, calculate_inner_height(box, available_space.height, computed_values.min_height()).to_px(box));
|
||
}
|
||
|
||
if (box.document().in_quirks_mode()
|
||
&& box.dom_node()
|
||
&& box.dom_node()->is_html_html_element()
|
||
&& box.computed_values().height().is_auto()) {
|
||
// 3.6. The html element fills the viewport quirk
|
||
// https://quirks.spec.whatwg.org/#the-html-element-fills-the-viewport-quirk
|
||
// FIXME: Handle vertical writing mode.
|
||
|
||
auto& box_state = m_state.get_mutable(box);
|
||
|
||
// 1. Let margins be sum of the used values of the margin-left and margin-right properties of element
|
||
// if element has a vertical writing mode, otherwise let margins be the sum of the used values of
|
||
// the margin-top and margin-bottom properties of element.
|
||
auto margins = box_state.margin_top + box_state.margin_bottom;
|
||
|
||
// 2. Let size be the size of the initial containing block in the block flow direction minus margins.
|
||
auto size = box_state.content_height() - margins;
|
||
|
||
// 3. Return the bigger value of size and the normal border box size the element would have
|
||
// according to the CSS specification.
|
||
height = max(size, height);
|
||
}
|
||
|
||
m_state.get_mutable(box).set_content_height(height);
|
||
}
|
||
|
||
void BlockFormattingContext::layout_inline_children(BlockContainer const& block_container, LayoutMode layout_mode, AvailableSpace const& available_space)
|
||
{
|
||
VERIFY(block_container.children_are_inline());
|
||
|
||
auto& block_container_state = m_state.get_mutable(block_container);
|
||
|
||
InlineFormattingContext context(m_state, block_container, *this);
|
||
context.run(
|
||
block_container,
|
||
layout_mode,
|
||
available_space);
|
||
|
||
if (!block_container_state.has_definite_width())
|
||
block_container_state.set_content_width(context.automatic_content_width());
|
||
if (!block_container_state.has_definite_height())
|
||
block_container_state.set_content_height(context.automatic_content_height());
|
||
}
|
||
|
||
CSSPixels BlockFormattingContext::compute_auto_height_for_block_level_element(Box const& box, AvailableSpace const& available_space)
|
||
{
|
||
if (creates_block_formatting_context(box)) {
|
||
return compute_auto_height_for_block_formatting_context_root(box);
|
||
}
|
||
|
||
auto const& box_state = m_state.get(box);
|
||
|
||
auto display = box.display();
|
||
if (display.is_flex_inside()) {
|
||
// https://drafts.csswg.org/css-flexbox-1/#algo-main-container
|
||
// NOTE: The automatic block size of a block-level flex container is its max-content size.
|
||
return calculate_max_content_height(box, available_space.width);
|
||
}
|
||
if (display.is_grid_inside()) {
|
||
// https://www.w3.org/TR/css-grid-2/#intrinsic-sizes
|
||
// In both inline and block formatting contexts, the grid container’s auto block size is its
|
||
// max-content size.
|
||
return calculate_max_content_height(box, available_space.width);
|
||
}
|
||
if (display.is_table_inside()) {
|
||
return calculate_max_content_height(box, available_space.width);
|
||
}
|
||
|
||
// https://www.w3.org/TR/CSS22/visudet.html#normal-block
|
||
// 10.6.3 Block-level non-replaced elements in normal flow when 'overflow' computes to 'visible'
|
||
|
||
// The element's height is the distance from its top content edge to the first applicable of the following:
|
||
|
||
// 1. the bottom edge of the last line box, if the box establishes a inline formatting context with one or more lines
|
||
if (box.children_are_inline() && !box_state.line_boxes.is_empty())
|
||
return box_state.line_boxes.last().bottom().value();
|
||
|
||
// 2. the bottom edge of the bottom (possibly collapsed) margin of its last in-flow child, if the child's bottom margin does not collapse with the element's bottom margin
|
||
// 3. the bottom border edge of the last in-flow child whose top margin doesn't collapse with the element's bottom margin
|
||
if (!box.children_are_inline()) {
|
||
for (auto* child_box = box.last_child_of_type<Box>(); child_box; child_box = child_box->previous_sibling_of_type<Box>()) {
|
||
if (child_box->is_absolutely_positioned() || child_box->is_floating())
|
||
continue;
|
||
|
||
// FIXME: This is hack. If the last child is a list-item marker box, we ignore it for purposes of height calculation.
|
||
// Perhaps markers should not be considered in-flow(?) Perhaps they should always be the first child of the list-item
|
||
// box instead of the last child.
|
||
if (child_box->is_list_item_marker_box())
|
||
continue;
|
||
|
||
auto const& child_box_state = m_state.get(*child_box);
|
||
|
||
// Ignore anonymous block containers with no lines. These don't count as in-flow block boxes.
|
||
if (!child_box->is_table_wrapper() && child_box->is_anonymous() && child_box->is_block_container() && child_box_state.line_boxes.is_empty())
|
||
continue;
|
||
|
||
auto margin_bottom = m_margin_state.current_collapsed_margin();
|
||
if (box_state.padding_bottom == 0 && box_state.border_bottom == 0) {
|
||
m_margin_state.box_last_in_flow_child_margin_bottom_collapsed = true;
|
||
margin_bottom = 0;
|
||
}
|
||
|
||
return max(0.0f, (child_box_state.offset.y() + child_box_state.content_height() + child_box_state.border_box_bottom() + margin_bottom).value());
|
||
}
|
||
}
|
||
|
||
// 4. zero, otherwise
|
||
return 0;
|
||
}
|
||
|
||
void BlockFormattingContext::layout_block_level_box(Box const& box, BlockContainer const& block_container, LayoutMode layout_mode, CSSPixels& bottom_of_lowest_margin_box, AvailableSpace const& available_space)
|
||
{
|
||
auto& box_state = m_state.get_mutable(box);
|
||
|
||
if (box.is_absolutely_positioned()) {
|
||
m_absolutely_positioned_boxes.append(box);
|
||
return;
|
||
}
|
||
|
||
// NOTE: ListItemMarkerBoxes are placed by their corresponding ListItemBox.
|
||
if (is<ListItemMarkerBox>(box))
|
||
return;
|
||
|
||
resolve_vertical_box_model_metrics(box);
|
||
|
||
if (box.is_floating()) {
|
||
auto const y = m_y_offset_of_current_block_container.value();
|
||
auto margin_top = !m_margin_state.has_block_container_waiting_for_final_y_position() ? m_margin_state.current_collapsed_margin() : 0;
|
||
layout_floating_box(box, block_container, layout_mode, available_space, margin_top + y);
|
||
bottom_of_lowest_margin_box = max(bottom_of_lowest_margin_box, box_state.offset.y() + box_state.content_height() + box_state.margin_box_bottom());
|
||
return;
|
||
}
|
||
|
||
m_margin_state.add_margin(box_state.margin_top);
|
||
auto introduce_clearance = clear_floating_boxes(box);
|
||
if (introduce_clearance == DidIntroduceClearance::Yes)
|
||
m_margin_state.reset();
|
||
|
||
auto const y = m_y_offset_of_current_block_container.value();
|
||
|
||
if (box_state.has_definite_height()) {
|
||
compute_height(box, available_space);
|
||
}
|
||
|
||
auto independent_formatting_context = create_independent_formatting_context_if_needed(m_state, box);
|
||
|
||
m_margin_state.update_block_waiting_for_final_y_position();
|
||
CSSPixels margin_top = m_margin_state.current_collapsed_margin();
|
||
|
||
if (m_margin_state.has_block_container_waiting_for_final_y_position()) {
|
||
// If first child margin top will collapse with margin-top of containing block then margin-top of child is 0
|
||
margin_top = 0;
|
||
}
|
||
|
||
if (independent_formatting_context) {
|
||
// Margins of elements that establish new formatting contexts do not collapse with their in-flow children
|
||
m_margin_state.reset();
|
||
}
|
||
|
||
place_block_level_element_in_normal_flow_vertically(box, y + margin_top);
|
||
|
||
compute_width(box, available_space, layout_mode);
|
||
|
||
place_block_level_element_in_normal_flow_horizontally(box, available_space);
|
||
|
||
if (box.is_replaced_box())
|
||
compute_height(box, available_space);
|
||
|
||
if (independent_formatting_context) {
|
||
// This box establishes a new formatting context. Pass control to it.
|
||
independent_formatting_context->run(box, layout_mode, box_state.available_inner_space_or_constraints_from(available_space));
|
||
} else {
|
||
// This box participates in the current block container's flow.
|
||
if (box.children_are_inline()) {
|
||
layout_inline_children(verify_cast<BlockContainer>(box), layout_mode, box_state.available_inner_space_or_constraints_from(available_space));
|
||
} else {
|
||
if (box_state.border_top > 0 || box_state.padding_top > 0) {
|
||
// margin-top of block container can't collapse with it's children if it has non zero border or padding
|
||
m_margin_state.reset();
|
||
} else if (!m_margin_state.has_block_container_waiting_for_final_y_position()) {
|
||
// margin-top of block container can be updated during children layout hence it's final y position yet to be determined
|
||
m_margin_state.register_block_container_y_position_update_callback([&](CSSPixels margin_top) {
|
||
if (introduce_clearance == DidIntroduceClearance::No) {
|
||
place_block_level_element_in_normal_flow_vertically(box, margin_top + y);
|
||
}
|
||
});
|
||
}
|
||
|
||
layout_block_level_children(verify_cast<BlockContainer>(box), layout_mode, box_state.available_inner_space_or_constraints_from(available_space));
|
||
}
|
||
}
|
||
|
||
compute_height(box, available_space);
|
||
|
||
if (independent_formatting_context || !margins_collapse_through(box, m_state)) {
|
||
if (!m_margin_state.box_last_in_flow_child_margin_bottom_collapsed) {
|
||
m_margin_state.reset();
|
||
}
|
||
m_y_offset_of_current_block_container = box_state.offset.y() + box_state.content_height() + box_state.border_box_bottom();
|
||
}
|
||
m_margin_state.box_last_in_flow_child_margin_bottom_collapsed = false;
|
||
|
||
m_margin_state.add_margin(box_state.margin_bottom);
|
||
m_margin_state.update_block_waiting_for_final_y_position();
|
||
|
||
compute_inset(box);
|
||
|
||
if (is<ListItemBox>(box)) {
|
||
layout_list_item_marker(static_cast<ListItemBox const&>(box));
|
||
}
|
||
|
||
bottom_of_lowest_margin_box = max(bottom_of_lowest_margin_box, box_state.offset.y() + box_state.content_height() + box_state.margin_box_bottom());
|
||
|
||
if (independent_formatting_context)
|
||
independent_formatting_context->parent_context_did_dimension_child_root_box();
|
||
}
|
||
|
||
void BlockFormattingContext::layout_block_level_children(BlockContainer const& block_container, LayoutMode layout_mode, AvailableSpace const& available_space)
|
||
{
|
||
VERIFY(!block_container.children_are_inline());
|
||
|
||
CSSPixels bottom_of_lowest_margin_box = 0;
|
||
|
||
TemporaryChange<Optional<CSSPixels>> change { m_y_offset_of_current_block_container, CSSPixels(0) };
|
||
block_container.for_each_child_of_type<Box>([&](Box& box) {
|
||
layout_block_level_box(box, block_container, layout_mode, bottom_of_lowest_margin_box, available_space);
|
||
return IterationDecision::Continue;
|
||
});
|
||
|
||
m_margin_state.block_container_y_position_update_callback = {};
|
||
|
||
if (layout_mode == LayoutMode::IntrinsicSizing) {
|
||
auto& block_container_state = m_state.get_mutable(block_container);
|
||
if (!block_container_state.has_definite_width())
|
||
block_container_state.set_content_width(greatest_child_width(block_container));
|
||
if (!block_container_state.has_definite_height())
|
||
block_container_state.set_content_height(bottom_of_lowest_margin_box);
|
||
}
|
||
}
|
||
|
||
void BlockFormattingContext::resolve_vertical_box_model_metrics(Box const& box)
|
||
{
|
||
auto& box_state = m_state.get_mutable(box);
|
||
auto const& computed_values = box.computed_values();
|
||
auto width_of_containing_block = containing_block_width_for(box);
|
||
|
||
box_state.margin_top = computed_values.margin().top().to_px(box, width_of_containing_block);
|
||
box_state.margin_bottom = computed_values.margin().bottom().to_px(box, width_of_containing_block);
|
||
box_state.border_top = computed_values.border_top().width;
|
||
box_state.border_bottom = computed_values.border_bottom().width;
|
||
box_state.padding_top = computed_values.padding().top().to_px(box, width_of_containing_block);
|
||
box_state.padding_bottom = computed_values.padding().bottom().to_px(box, width_of_containing_block);
|
||
}
|
||
|
||
CSSPixels BlockFormattingContext::BlockMarginState::current_collapsed_margin() const
|
||
{
|
||
CSSPixels smallest_margin = 0;
|
||
CSSPixels largest_margin = 0;
|
||
size_t negative_margin_count = 0;
|
||
for (auto margin : current_collapsible_margins) {
|
||
if (margin < 0)
|
||
++negative_margin_count;
|
||
largest_margin = max(largest_margin, margin);
|
||
smallest_margin = min(smallest_margin, margin);
|
||
}
|
||
|
||
CSSPixels collapsed_margin = 0;
|
||
if (negative_margin_count == current_collapsible_margins.size()) {
|
||
// When all margins are negative, the size of the collapsed margin is the smallest (most negative) margin.
|
||
collapsed_margin = smallest_margin;
|
||
} else if (negative_margin_count > 0) {
|
||
// When negative margins are involved, the size of the collapsed margin is the sum of the largest positive margin and the smallest (most negative) negative margin.
|
||
collapsed_margin = largest_margin + smallest_margin;
|
||
} else {
|
||
// Otherwise, collapse all the adjacent margins by using only the largest one.
|
||
collapsed_margin = largest_margin;
|
||
}
|
||
|
||
return collapsed_margin;
|
||
}
|
||
|
||
BlockFormattingContext::DidIntroduceClearance BlockFormattingContext::clear_floating_boxes(Box const& child_box)
|
||
{
|
||
auto const& computed_values = child_box.computed_values();
|
||
auto result = DidIntroduceClearance::No;
|
||
|
||
auto clear_floating_boxes = [&](FloatSideData& float_side) {
|
||
if (!float_side.current_boxes.is_empty()) {
|
||
// NOTE: Floating boxes are globally relevant within this BFC, *but* their offset coordinates
|
||
// are relative to their containing block.
|
||
// This means that we have to first convert to a root-space Y coordinate before clearing,
|
||
// and then convert back to a local Y coordinate when assigning the cleared offset to
|
||
// the `child_box` layout state.
|
||
|
||
// First, find the lowest margin box edge on this float side and calculate the Y offset just below it.
|
||
CSSPixels clearance_y_in_root = 0;
|
||
for (auto const& floating_box : float_side.current_boxes) {
|
||
auto floating_box_rect_in_root = margin_box_rect_in_ancestor_coordinate_space(floating_box.box, root(), m_state);
|
||
clearance_y_in_root = max(clearance_y_in_root, floating_box_rect_in_root.bottom());
|
||
}
|
||
|
||
// Then, convert the clearance Y to a coordinate relative to the containing block of `child_box`.
|
||
CSSPixels clearance_y_in_containing_block = clearance_y_in_root;
|
||
for (auto* containing_block = child_box.containing_block(); containing_block && containing_block != &root(); containing_block = containing_block->containing_block())
|
||
clearance_y_in_containing_block -= m_state.get(*containing_block).offset.y();
|
||
|
||
if (clearance_y_in_containing_block > m_y_offset_of_current_block_container.value()) {
|
||
result = DidIntroduceClearance::Yes;
|
||
m_y_offset_of_current_block_container = clearance_y_in_containing_block;
|
||
}
|
||
|
||
float_side.clear();
|
||
}
|
||
};
|
||
|
||
// Flex-items don't float and also don't clear.
|
||
if ((computed_values.clear() == CSS::Clear::Left || computed_values.clear() == CSS::Clear::Both) && !child_box.is_flex_item())
|
||
clear_floating_boxes(m_left_floats);
|
||
if ((computed_values.clear() == CSS::Clear::Right || computed_values.clear() == CSS::Clear::Both) && !child_box.is_flex_item())
|
||
clear_floating_boxes(m_right_floats);
|
||
|
||
return result;
|
||
}
|
||
|
||
void BlockFormattingContext::place_block_level_element_in_normal_flow_vertically(Box const& child_box, CSSPixels y)
|
||
{
|
||
auto& box_state = m_state.get_mutable(child_box);
|
||
y += box_state.border_box_top();
|
||
box_state.set_content_offset(CSSPixelPoint { box_state.offset.x(), y.value() });
|
||
}
|
||
|
||
void BlockFormattingContext::place_block_level_element_in_normal_flow_horizontally(Box const& child_box, AvailableSpace const& available_space)
|
||
{
|
||
auto& box_state = m_state.get_mutable(child_box);
|
||
|
||
CSSPixels x = 0;
|
||
CSSPixels available_width_within_containing_block = available_space.width.to_px();
|
||
|
||
if ((!m_left_floats.current_boxes.is_empty() || !m_right_floats.current_boxes.is_empty())
|
||
&& creates_block_formatting_context(child_box)) {
|
||
auto box_in_root_rect = content_box_rect_in_ancestor_coordinate_space(child_box, root(), m_state);
|
||
auto space = space_used_by_floats(box_in_root_rect.y());
|
||
available_width_within_containing_block -= space.left + space.right;
|
||
x += space.left;
|
||
}
|
||
|
||
if (child_box.containing_block()->computed_values().text_align() == CSS::TextAlign::LibwebCenter) {
|
||
x += (available_width_within_containing_block / 2) - box_state.content_width() / 2;
|
||
} else {
|
||
x += box_state.margin_box_left();
|
||
}
|
||
|
||
box_state.set_content_offset({ x.value(), box_state.offset.y() });
|
||
}
|
||
|
||
static void measure_scrollable_overflow(LayoutState const& state, Box const& box, CSSPixels& bottom_edge, CSSPixels& right_edge)
|
||
{
|
||
auto const& child_state = state.get(box);
|
||
auto child_rect = absolute_content_rect(box, state);
|
||
child_rect.inflate(child_state.border_box_top(), child_state.border_box_right(), child_state.border_box_bottom(), child_state.border_box_left());
|
||
|
||
bottom_edge = max(bottom_edge, child_rect.bottom() - 1);
|
||
right_edge = max(right_edge, child_rect.right() - 1);
|
||
|
||
if (box.computed_values().overflow_x() == CSS::Overflow::Hidden && box.computed_values().overflow_y() == CSS::Overflow::Hidden)
|
||
return;
|
||
|
||
if (box.children_are_inline()) {
|
||
if (!child_state.line_boxes.is_empty()) {
|
||
bottom_edge = max(bottom_edge, child_rect.y() + child_state.line_boxes.last().bottom());
|
||
for (auto& line_box : child_state.line_boxes) {
|
||
if (line_box.fragments().is_empty())
|
||
continue;
|
||
right_edge = max(right_edge, child_rect.x() + line_box.fragments().last().width());
|
||
}
|
||
}
|
||
} else {
|
||
box.for_each_child_of_type<Box>([&](Box const& child) {
|
||
measure_scrollable_overflow(state, child, bottom_edge, right_edge);
|
||
return IterationDecision::Continue;
|
||
});
|
||
}
|
||
}
|
||
|
||
void BlockFormattingContext::layout_viewport(LayoutMode layout_mode, AvailableSpace const& available_space)
|
||
{
|
||
auto viewport_rect = root().browsing_context().viewport_rect();
|
||
|
||
auto& viewport = verify_cast<Layout::Viewport>(root());
|
||
auto& viewport_state = m_state.get_mutable(viewport);
|
||
|
||
// NOTE: If we are laying out a standalone SVG document, we give it some special treatment:
|
||
// The root <svg> container gets the same size as the viewport,
|
||
// and we call directly into the SVG layout code from here.
|
||
if (root().first_child() && root().first_child()->is_svg_svg_box()) {
|
||
auto const& svg_root = verify_cast<SVGSVGBox>(*root().first_child());
|
||
auto svg_formatting_context = create_independent_formatting_context_if_needed(m_state, svg_root);
|
||
svg_formatting_context->run(svg_root, layout_mode, available_space);
|
||
} else {
|
||
if (root().children_are_inline())
|
||
layout_inline_children(root(), layout_mode, available_space);
|
||
else
|
||
layout_block_level_children(root(), layout_mode, available_space);
|
||
}
|
||
|
||
CSSPixels bottom_edge = 0;
|
||
CSSPixels right_edge = 0;
|
||
measure_scrollable_overflow(m_state, viewport, bottom_edge, right_edge);
|
||
|
||
if (bottom_edge >= viewport_rect.height() || right_edge >= viewport_rect.width()) {
|
||
// FIXME: Move overflow data to LayoutState!
|
||
auto& overflow_data = viewport_state.ensure_overflow_data();
|
||
overflow_data.scrollable_overflow_rect = viewport_rect;
|
||
// NOTE: The edges are *within* the rectangle, so we add 1 to get the width and height.
|
||
overflow_data.scrollable_overflow_rect.set_size(right_edge + 1, bottom_edge + 1);
|
||
}
|
||
}
|
||
|
||
void BlockFormattingContext::layout_floating_box(Box const& box, BlockContainer const&, LayoutMode layout_mode, AvailableSpace const& available_space, CSSPixels y, LineBuilder* line_builder)
|
||
{
|
||
VERIFY(box.is_floating());
|
||
|
||
auto& box_state = m_state.get_mutable(box);
|
||
CSSPixels width_of_containing_block = available_space.width.to_px();
|
||
|
||
resolve_vertical_box_model_metrics(box);
|
||
|
||
compute_width(box, available_space, layout_mode);
|
||
auto independent_formatting_context = layout_inside(box, layout_mode, box_state.available_inner_space_or_constraints_from(available_space));
|
||
compute_height(box, available_space);
|
||
|
||
// First we place the box normally (to get the right y coordinate.)
|
||
// If we have a LineBuilder, we're in the middle of inline layout, otherwise this is block layout.
|
||
if (line_builder) {
|
||
auto y = line_builder->y_for_float_to_be_inserted_here(box);
|
||
box_state.set_content_y(y + box_state.margin_box_top());
|
||
} else {
|
||
place_block_level_element_in_normal_flow_vertically(box, y + box_state.margin_top);
|
||
place_block_level_element_in_normal_flow_horizontally(box, available_space);
|
||
}
|
||
|
||
// Then we float it to the left or right.
|
||
auto float_box = [&](FloatSide side, FloatSideData& side_data, FloatSideData& other_side_data) {
|
||
CSSPixels offset_from_edge = 0;
|
||
auto float_to_edge = [&] {
|
||
if (side == FloatSide::Left)
|
||
offset_from_edge = box_state.margin_box_left();
|
||
else
|
||
offset_from_edge = box_state.content_width() + box_state.margin_box_right();
|
||
};
|
||
|
||
auto box_in_root_rect = content_box_rect_in_ancestor_coordinate_space(box, root(), m_state);
|
||
CSSPixels y_in_root = box_in_root_rect.y();
|
||
CSSPixels y = box_state.offset.y();
|
||
|
||
if (side_data.current_boxes.is_empty()) {
|
||
// This is the first floating box on this side. Go all the way to the edge.
|
||
float_to_edge();
|
||
side_data.y_offset = 0;
|
||
} else {
|
||
|
||
// NOTE: If we're in inline layout, the LineBuilder has already provided the right Y offset.
|
||
// In block layout, we adjust by the side's current Y offset here.
|
||
if (!line_builder)
|
||
y_in_root += side_data.y_offset;
|
||
|
||
bool did_touch_preceding_float = false;
|
||
bool did_place_next_to_preceding_float = false;
|
||
|
||
// Walk all currently tracked floats on the side we're floating towards.
|
||
// We're looking for the innermost preceding float that intersects vertically with `box`.
|
||
for (auto& preceding_float : side_data.current_boxes.in_reverse()) {
|
||
auto const preceding_float_rect = margin_box_rect_in_ancestor_coordinate_space(preceding_float.box, root(), m_state);
|
||
if (!preceding_float_rect.contains_vertically(y_in_root))
|
||
continue;
|
||
// We found a preceding float that intersects vertically with the current float.
|
||
// Now we need to find out if there's enough inline-axis space to stack them next to each other.
|
||
auto const& preceding_float_state = m_state.get(preceding_float.box);
|
||
CSSPixels tentative_offset_from_edge = 0;
|
||
bool fits_next_to_preceding_float = false;
|
||
if (side == FloatSide::Left) {
|
||
tentative_offset_from_edge = preceding_float.offset_from_edge + preceding_float_state.content_width() + preceding_float_state.margin_box_right() + box_state.margin_box_left();
|
||
fits_next_to_preceding_float = (tentative_offset_from_edge + box_state.content_width() + box_state.margin_box_right()) <= width_of_containing_block;
|
||
} else {
|
||
tentative_offset_from_edge = preceding_float.offset_from_edge + preceding_float_state.margin_box_left() + box_state.margin_box_right() + box_state.content_width();
|
||
fits_next_to_preceding_float = tentative_offset_from_edge >= 0;
|
||
}
|
||
did_touch_preceding_float = true;
|
||
if (!fits_next_to_preceding_float)
|
||
break;
|
||
offset_from_edge = tentative_offset_from_edge;
|
||
did_place_next_to_preceding_float = true;
|
||
break;
|
||
}
|
||
|
||
if (!did_touch_preceding_float || !did_place_next_to_preceding_float) {
|
||
// One of two things happened:
|
||
// - This box does not touch another floating box.
|
||
// - We ran out of horizontal space on this "float line", and need to break.
|
||
// Either way, we float this box all the way to the edge.
|
||
float_to_edge();
|
||
CSSPixels lowest_margin_edge = 0;
|
||
for (auto const& box : side_data.current_boxes) {
|
||
auto const& box_state = m_state.get(box.box);
|
||
lowest_margin_edge = max(lowest_margin_edge, box_state.margin_box_height());
|
||
}
|
||
|
||
side_data.y_offset += lowest_margin_edge;
|
||
|
||
// Also, forget all previous boxes floated to this side while since they're no longer relevant.
|
||
side_data.clear();
|
||
}
|
||
}
|
||
|
||
// NOTE: If we're in inline layout, the LineBuilder has already provided the right Y offset.
|
||
// In block layout, we adjust by the side's current Y offset here.
|
||
// FIXME: It's annoying that we have different behavior for inline vs block here.
|
||
// Find a way to unify the behavior so we don't need to branch here.
|
||
|
||
if (!line_builder)
|
||
y += side_data.y_offset;
|
||
|
||
side_data.all_boxes.append(adopt_own(*new FloatingBox {
|
||
.box = box,
|
||
.offset_from_edge = offset_from_edge,
|
||
.top_margin_edge = y - box_state.margin_box_top(),
|
||
.bottom_margin_edge = y + box_state.content_height() + box_state.margin_box_bottom(),
|
||
}));
|
||
side_data.current_boxes.append(*side_data.all_boxes.last());
|
||
|
||
if (side == FloatSide::Left) {
|
||
side_data.current_width = offset_from_edge + box_state.content_width() + box_state.margin_box_right();
|
||
} else {
|
||
side_data.current_width = offset_from_edge + box_state.margin_box_left();
|
||
}
|
||
side_data.max_width = max(side_data.current_width, side_data.max_width);
|
||
|
||
// NOTE: We don't set the X position here, that happens later, once we know the root block width.
|
||
// See parent_context_did_dimension_child_root_box() for that logic.
|
||
box_state.set_content_y(y.value());
|
||
|
||
// If the new box was inserted below the bottom of the opposite side,
|
||
// we reset the other side back to its edge.
|
||
if (y > other_side_data.y_offset)
|
||
other_side_data.clear();
|
||
};
|
||
|
||
// Next, float to the left and/or right
|
||
if (box.computed_values().float_() == CSS::Float::Left) {
|
||
float_box(FloatSide::Left, m_left_floats, m_right_floats);
|
||
} else if (box.computed_values().float_() == CSS::Float::Right) {
|
||
float_box(FloatSide::Right, m_right_floats, m_left_floats);
|
||
}
|
||
|
||
m_state.get_mutable(root()).add_floating_descendant(box);
|
||
|
||
if (line_builder)
|
||
line_builder->recalculate_available_space();
|
||
|
||
if (independent_formatting_context)
|
||
independent_formatting_context->parent_context_did_dimension_child_root_box();
|
||
}
|
||
|
||
void BlockFormattingContext::layout_list_item_marker(ListItemBox const& list_item_box)
|
||
{
|
||
if (!list_item_box.marker())
|
||
return;
|
||
|
||
auto& marker = *list_item_box.marker();
|
||
auto& marker_state = m_state.get_mutable(marker);
|
||
auto& list_item_state = m_state.get_mutable(list_item_box);
|
||
|
||
CSSPixels image_width = 0;
|
||
CSSPixels image_height = 0;
|
||
if (auto const* list_style_image = marker.list_style_image()) {
|
||
image_width = list_style_image->natural_width().value_or(0);
|
||
image_height = list_style_image->natural_height().value_or(0);
|
||
}
|
||
|
||
CSSPixels default_marker_width = max(4, marker.font().pixel_size_rounded_up() - 4);
|
||
|
||
if (marker.text().is_empty()) {
|
||
marker_state.set_content_width((image_width + default_marker_width).value());
|
||
} else {
|
||
auto text_width = marker.font().width(marker.text());
|
||
marker_state.set_content_width((image_width + text_width).value());
|
||
}
|
||
|
||
marker_state.set_content_height(max(image_height, marker.font().pixel_size_rounded_up() + 1).value());
|
||
|
||
marker_state.set_content_offset({ -(marker_state.content_width() + default_marker_width),
|
||
max(CSSPixels(0), (CSSPixels(marker.line_height()) - marker_state.content_height()) / 2) });
|
||
|
||
if (marker_state.content_height() > list_item_state.content_height())
|
||
list_item_state.set_content_height(marker_state.content_height());
|
||
}
|
||
|
||
BlockFormattingContext::SpaceUsedByFloats BlockFormattingContext::space_used_by_floats(CSSPixels y) const
|
||
{
|
||
SpaceUsedByFloats space_used_by_floats;
|
||
|
||
for (auto const& floating_box_ptr : m_left_floats.all_boxes.in_reverse()) {
|
||
auto const& floating_box = *floating_box_ptr;
|
||
auto const& floating_box_state = m_state.get(floating_box.box);
|
||
// NOTE: The floating box is *not* in the final horizontal position yet, but the size and vertical position is valid.
|
||
auto rect = margin_box_rect_in_ancestor_coordinate_space(floating_box.box, root(), m_state);
|
||
if (rect.contains_vertically(y.value())) {
|
||
CSSPixels offset_from_containing_block_chain_margins_between_here_and_root = 0;
|
||
for (auto const* containing_block = floating_box.box->containing_block(); containing_block && containing_block != &root(); containing_block = containing_block->containing_block()) {
|
||
auto const& containing_block_state = m_state.get(*containing_block);
|
||
offset_from_containing_block_chain_margins_between_here_and_root += containing_block_state.margin_box_left();
|
||
}
|
||
space_used_by_floats.left = offset_from_containing_block_chain_margins_between_here_and_root
|
||
+ floating_box.offset_from_edge
|
||
+ floating_box_state.content_width()
|
||
+ floating_box_state.margin_box_right();
|
||
break;
|
||
}
|
||
}
|
||
|
||
for (auto const& floating_box_ptr : m_right_floats.all_boxes.in_reverse()) {
|
||
auto const& floating_box = *floating_box_ptr;
|
||
auto const& floating_box_state = m_state.get(floating_box.box);
|
||
// NOTE: The floating box is *not* in the final horizontal position yet, but the size and vertical position is valid.
|
||
auto rect = margin_box_rect_in_ancestor_coordinate_space(floating_box.box, root(), m_state);
|
||
if (rect.contains_vertically(y.value())) {
|
||
CSSPixels offset_from_containing_block_chain_margins_between_here_and_root = 0;
|
||
for (auto const* containing_block = floating_box.box->containing_block(); containing_block && containing_block != &root(); containing_block = containing_block->containing_block()) {
|
||
auto const& containing_block_state = m_state.get(*containing_block);
|
||
offset_from_containing_block_chain_margins_between_here_and_root += containing_block_state.margin_box_right();
|
||
}
|
||
space_used_by_floats.right = offset_from_containing_block_chain_margins_between_here_and_root
|
||
+ floating_box.offset_from_edge
|
||
+ floating_box_state.margin_box_left();
|
||
break;
|
||
}
|
||
}
|
||
|
||
return space_used_by_floats;
|
||
}
|
||
|
||
FormattingContext::SpaceUsedByFloats BlockFormattingContext::intrusion_by_floats_into_box(Box const& box, CSSPixels y_in_box) const
|
||
{
|
||
// NOTE: Floats are relative to the BFC root box, not necessarily the containing block of this IFC.
|
||
auto box_in_root_rect = content_box_rect_in_ancestor_coordinate_space(box, root(), m_state);
|
||
CSSPixels y_in_root = box_in_root_rect.y() + y_in_box;
|
||
auto space_used_by_floats_in_root = space_used_by_floats(y_in_root);
|
||
|
||
auto left_intrusion = max(CSSPixels(0), space_used_by_floats_in_root.left - box_in_root_rect.x());
|
||
|
||
CSSPixels offset_from_containing_block_chain_margins_between_here_and_root = 0;
|
||
for (auto const* containing_block = static_cast<Box const*>(&box); containing_block && containing_block != &root(); containing_block = containing_block->containing_block()) {
|
||
auto const& containing_block_state = m_state.get(*containing_block);
|
||
offset_from_containing_block_chain_margins_between_here_and_root = max(offset_from_containing_block_chain_margins_between_here_and_root, containing_block_state.margin_box_right());
|
||
}
|
||
auto right_intrusion = max(CSSPixels(0), space_used_by_floats_in_root.right - offset_from_containing_block_chain_margins_between_here_and_root);
|
||
|
||
return { left_intrusion, right_intrusion };
|
||
}
|
||
|
||
CSSPixels BlockFormattingContext::greatest_child_width(Box const& box) const
|
||
{
|
||
// Similar to FormattingContext::greatest_child_width()
|
||
// but this one takes floats into account!
|
||
CSSPixels max_width = m_left_floats.max_width + m_right_floats.max_width;
|
||
if (box.children_are_inline()) {
|
||
for (auto const& line_box : m_state.get(verify_cast<BlockContainer>(box)).line_boxes) {
|
||
CSSPixels width_here = line_box.width();
|
||
CSSPixels extra_width_from_left_floats = 0;
|
||
for (auto& left_float : m_left_floats.all_boxes) {
|
||
// NOTE: Floats directly affect the automatic size of their containing block, but only indirectly anything above in the tree.
|
||
if (left_float->box->containing_block() != &box)
|
||
continue;
|
||
if (line_box.baseline() >= left_float->top_margin_edge.value() || line_box.baseline() <= left_float->bottom_margin_edge.value()) {
|
||
auto const& left_float_state = m_state.get(left_float->box);
|
||
extra_width_from_left_floats = max(extra_width_from_left_floats, left_float->offset_from_edge + left_float_state.content_width() + left_float_state.margin_box_right());
|
||
}
|
||
}
|
||
CSSPixels extra_width_from_right_floats = 0;
|
||
for (auto& right_float : m_right_floats.all_boxes) {
|
||
// NOTE: Floats directly affect the automatic size of their containing block, but only indirectly anything above in the tree.
|
||
if (right_float->box->containing_block() != &box)
|
||
continue;
|
||
if (line_box.baseline() >= right_float->top_margin_edge.value() || line_box.baseline() <= right_float->bottom_margin_edge.value()) {
|
||
auto const& right_float_state = m_state.get(right_float->box);
|
||
extra_width_from_right_floats = max(extra_width_from_right_floats, right_float->offset_from_edge + right_float_state.margin_box_left());
|
||
}
|
||
}
|
||
width_here += extra_width_from_left_floats + extra_width_from_right_floats;
|
||
max_width = max(max_width, width_here);
|
||
}
|
||
} else {
|
||
box.for_each_child_of_type<Box>([&](Box const& child) {
|
||
if (!child.is_absolutely_positioned())
|
||
max_width = max(max_width, m_state.get(child).margin_box_width());
|
||
});
|
||
}
|
||
return max_width;
|
||
}
|
||
|
||
void BlockFormattingContext::determine_width_of_child(Box const&, AvailableSpace const&)
|
||
{
|
||
// NOTE: We don't do anything here, since we'll have already determined the width of the child
|
||
// before recursing into nested layout within the child.
|
||
}
|
||
|
||
void BlockFormattingContext::determine_height_of_child(Box const& box, AvailableSpace const& available_space)
|
||
{
|
||
compute_height(box, available_space);
|
||
}
|
||
|
||
}
|