diff options
| -rw-r--r-- | components/layout_2020/flow/mod.rs | 374 |
1 files changed, 226 insertions, 148 deletions
diff --git a/components/layout_2020/flow/mod.rs b/components/layout_2020/flow/mod.rs index e881ed61347..2d1da5a570b 100644 --- a/components/layout_2020/flow/mod.rs +++ b/components/layout_2020/flow/mod.rs @@ -488,13 +488,13 @@ impl BlockLevelBox { containing_block, style, |positioning_context| { - layout_in_flow_non_replaced_block_level( + layout_in_flow_non_replaced_block_level_same_formatting_context( layout_context, positioning_context, containing_block, *tag, style, - NonReplacedContents::SameFormattingContextBlock(contents), + contents, sequential_layout_state, collapsible_with_parent_start_margin, ) @@ -523,17 +523,14 @@ impl BlockLevelBox { containing_block, &non_replaced.style, |positioning_context| { - layout_in_flow_non_replaced_block_level( + layout_in_flow_non_replaced_block_level_independent_formatting_context( layout_context, positioning_context, containing_block, non_replaced.base_fragment_info, &non_replaced.style, - NonReplacedContents::EstablishesAnIndependentFormattingContext( - non_replaced, - ), + non_replaced, sequential_layout_state, - collapsible_with_parent_start_margin, ) }, )) @@ -581,93 +578,33 @@ impl BlockLevelBox { } } -enum NonReplacedContents<'a> { - SameFormattingContextBlock(&'a BlockContainer), - EstablishesAnIndependentFormattingContext(&'a NonReplacedFormattingContext), -} - -/// https://drafts.csswg.org/css2/visudet.html#blockwidth -/// https://drafts.csswg.org/css2/visudet.html#normal-block -fn layout_in_flow_non_replaced_block_level( +/// Lay out a normal flow non-replaced block that does not establish a new formatting +/// context. +/// +/// - https://drafts.csswg.org/css2/visudet.html#blockwidth +/// - https://drafts.csswg.org/css2/visudet.html#normal-block +fn layout_in_flow_non_replaced_block_level_same_formatting_context( layout_context: &LayoutContext, positioning_context: &mut PositioningContext, containing_block: &ContainingBlock, base_fragment_info: BaseFragmentInfo, style: &Arc<ComputedValues>, - block_level_kind: NonReplacedContents, + contents: &BlockContainer, mut sequential_layout_state: Option<&mut SequentialLayoutState>, collapsible_with_parent_start_margin: Option<CollapsibleWithParentStartMargin>, ) -> BoxFragment { - let pbm = style.padding_border_margin(containing_block); - let box_size = style.content_box_size(containing_block, &pbm); - let max_box_size = style.content_max_box_size(containing_block, &pbm); - let min_box_size = style - .content_min_box_size(containing_block, &pbm) - .auto_is(Length::zero); - - // https://drafts.csswg.org/css2/visudet.html#min-max-widths - let solve_inline_margins = |inline_size| { - solve_inline_margins_for_in_flow_block_level(containing_block, &pbm, inline_size) - }; - let (mut inline_size, mut inline_margins) = - if let Some(inline_size) = box_size.inline.non_auto() { - (inline_size, solve_inline_margins(inline_size)) - } else { - let margin_inline_start = pbm.margin.inline_start.auto_is(Length::zero); - let margin_inline_end = pbm.margin.inline_end.auto_is(Length::zero); - let inline_size = containing_block.inline_size - - pbm.padding_border_sums.inline - - margin_inline_start - - margin_inline_end; - (inline_size, (margin_inline_start, margin_inline_end)) - }; - if let Some(max_inline_size) = max_box_size.inline { - if inline_size > max_inline_size { - inline_size = max_inline_size; - inline_margins = solve_inline_margins(inline_size); - } - } - if inline_size < min_box_size.inline { - inline_size = min_box_size.inline; - inline_margins = solve_inline_margins(inline_size); - } - - let margin = Sides { - inline_start: inline_margins.0, - inline_end: inline_margins.1, - block_start: pbm.margin.block_start.auto_is(Length::zero), - block_end: pbm.margin.block_end.auto_is(Length::zero), - }; - - // https://drafts.csswg.org/css2/visudet.html#min-max-heights - let mut block_size = box_size.block; - if let LengthOrAuto::LengthPercentage(ref mut block_size) = block_size { - *block_size = block_size.clamp_between_extremums(min_box_size.block, max_box_size.block); - } - - let containing_block_for_children = ContainingBlock { - inline_size, - block_size, - style, - }; - - // https://drafts.csswg.org/css-writing-modes/#orthogonal-flows - assert_eq!( - containing_block.style.writing_mode, containing_block_for_children.style.writing_mode, - "Mixed writing modes are not supported yet" - ); - - let block_is_same_formatting_context = match block_level_kind { - NonReplacedContents::SameFormattingContextBlock(_) => true, - NonReplacedContents::EstablishesAnIndependentFormattingContext(_) => false, - }; + let ContainingBlockPaddingBorderAndMargin { + containing_block: containing_block_for_children, + pbm, + min_box_size, + max_box_size, + margin, + } = solve_containing_block_padding_border_and_margin_for_in_flow_box(containing_block, style); let computed_block_size = style.content_block_size(); - let start_margin_can_collapse_with_children = block_is_same_formatting_context && - pbm.padding.block_start == Length::zero() && - pbm.border.block_start == Length::zero(); - let end_margin_can_collapse_with_children = block_is_same_formatting_context && - pbm.padding.block_end == Length::zero() && + let start_margin_can_collapse_with_children = + pbm.padding.block_start == Length::zero() && pbm.border.block_start == Length::zero(); + let end_margin_can_collapse_with_children = pbm.padding.block_end == Length::zero() && pbm.border.block_end == Length::zero() && computed_block_size.is_auto(); @@ -694,12 +631,9 @@ fn layout_in_flow_non_replaced_block_level( when laying out sequentially", ).0 && style.get_box().clear == Clear::None; if !collapsible_with_parent_start_margin && start_margin_can_collapse_with_children { - if let NonReplacedContents::SameFormattingContextBlock( - BlockContainer::BlockLevelBoxes(child_boxes), - ) = block_level_kind - { + if let BlockContainer::BlockLevelBoxes(child_boxes) = contents { BlockLevelBox::find_block_margin_collapsing_with_parent_from_slice( - child_boxes, + &child_boxes, &mut block_start_margin, containing_block, ); @@ -737,7 +671,7 @@ fn layout_in_flow_non_replaced_block_level( block_start: sequential_layout_state.bfc_relative_block_position, block_start_margins_not_collapsed: sequential_layout_state.current_margin, inline_start, - inline_end: inline_start + inline_size, + inline_end: inline_start + containing_block_for_children.inline_size, }; parent_containing_block_position_info = Some( sequential_layout_state.replace_containing_block_position_info(new_cb_offsets), @@ -745,65 +679,47 @@ fn layout_in_flow_non_replaced_block_level( }, }; + let flow_layout = contents.layout( + layout_context, + positioning_context, + &containing_block_for_children, + sequential_layout_state.as_mut().map(|x| &mut **x), + CollapsibleWithParentStartMargin(start_margin_can_collapse_with_children), + ); + let mut content_block_size = flow_layout.content_block_size; + + // Update margins. let mut block_margins_collapsed_with_children = CollapsedBlockMargins::from_margin(&margin); + let mut collapsible_margins_in_children = flow_layout.collapsible_margins_in_children; + if start_margin_can_collapse_with_children { + block_margins_collapsed_with_children + .start + .adjoin_assign(&collapsible_margins_in_children.start); + if collapsible_margins_in_children.collapsed_through { + block_margins_collapsed_with_children + .start + .adjoin_assign(&std::mem::replace( + &mut collapsible_margins_in_children.end, + CollapsedMargin::zero(), + )); + } + } + if end_margin_can_collapse_with_children { + block_margins_collapsed_with_children + .end + .adjoin_assign(&collapsible_margins_in_children.end); + } else { + content_block_size += collapsible_margins_in_children.end.solve(); + } - let fragments; - let mut content_block_size; - match block_level_kind { - NonReplacedContents::SameFormattingContextBlock(contents) => { - let flow_layout = contents.layout( - layout_context, - positioning_context, - &containing_block_for_children, - sequential_layout_state.as_mut().map(|x| &mut **x), - CollapsibleWithParentStartMargin(start_margin_can_collapse_with_children), - ); + let computed_min_block_size = style.min_block_size(); + block_margins_collapsed_with_children.collapsed_through = collapsible_margins_in_children + .collapsed_through && + pbm.padding_border_sums.block == Length::zero() && + (computed_block_size.is_definitely_zero() || computed_block_size.is_auto()) && + (computed_min_block_size.is_definitely_zero() || computed_min_block_size.is_auto()); - fragments = flow_layout.fragments; - content_block_size = flow_layout.content_block_size; - - // Update margins. - let mut collapsible_margins_in_children = flow_layout.collapsible_margins_in_children; - if start_margin_can_collapse_with_children { - block_margins_collapsed_with_children - .start - .adjoin_assign(&collapsible_margins_in_children.start); - if collapsible_margins_in_children.collapsed_through { - block_margins_collapsed_with_children - .start - .adjoin_assign(&std::mem::replace( - &mut collapsible_margins_in_children.end, - CollapsedMargin::zero(), - )); - } - } - if end_margin_can_collapse_with_children { - block_margins_collapsed_with_children - .end - .adjoin_assign(&collapsible_margins_in_children.end); - } else { - content_block_size += collapsible_margins_in_children.end.solve(); - } - let computed_min_block_size = style.min_block_size(); - block_margins_collapsed_with_children.collapsed_through = - collapsible_margins_in_children.collapsed_through && - pbm.padding_border_sums.block == Length::zero() && - (computed_block_size.is_definitely_zero() || computed_block_size.is_auto()) && - (computed_min_block_size.is_definitely_zero() || - computed_min_block_size.is_auto()); - }, - NonReplacedContents::EstablishesAnIndependentFormattingContext(non_replaced) => { - let independent_layout = non_replaced.layout( - layout_context, - positioning_context, - &containing_block_for_children, - ); - fragments = independent_layout.fragments; - content_block_size = independent_layout.content_block_size; - }, - }; - - let block_size = block_size.auto_is(|| { + let block_size = containing_block_for_children.block_size.auto_is(|| { content_block_size.clamp_between_extremums(min_box_size.block, max_box_size.block) }); @@ -835,14 +751,92 @@ fn layout_in_flow_non_replaced_block_level( }, size: Vec2 { block: block_size, - inline: inline_size, + inline: containing_block_for_children.inline_size, }, }; BoxFragment::new( base_fragment_info, style.clone(), - fragments, + flow_layout.fragments, + content_rect, + pbm.padding, + pbm.border, + margin, + clearance, + block_margins_collapsed_with_children, + ) +} + +/// Lay out a normal flow non-replaced block that establishes and independent formatting +/// context in its containing formatting context. +/// +/// - https://drafts.csswg.org/css2/visudet.html#blockwidth +/// - https://drafts.csswg.org/css2/visudet.html#normal-block +fn layout_in_flow_non_replaced_block_level_independent_formatting_context( + layout_context: &LayoutContext, + positioning_context: &mut PositioningContext, + containing_block: &ContainingBlock, + base_fragment_info: BaseFragmentInfo, + style: &Arc<ComputedValues>, + independent_formatting_context: &NonReplacedFormattingContext, + mut sequential_layout_state: Option<&mut SequentialLayoutState>, +) -> BoxFragment { + let ContainingBlockPaddingBorderAndMargin { + containing_block: containing_block_for_children, + pbm, + min_box_size, + max_box_size, + margin, + } = solve_containing_block_padding_border_and_margin_for_in_flow_box(containing_block, style); + + let layout = independent_formatting_context.layout( + layout_context, + positioning_context, + &containing_block_for_children, + ); + + let content_block_size = layout.content_block_size; + let block_size = containing_block_for_children.block_size.auto_is(|| { + content_block_size.clamp_between_extremums(min_box_size.block, max_box_size.block) + }); + + let mut clearance = None; + if let Some(ref mut sequential_layout_state) = sequential_layout_state { + clearance = sequential_layout_state.calculate_clearance_and_adjoin_margin( + style, + &CollapsedMargin::new(margin.block_start), + ); + sequential_layout_state.collapse_margins(); + + // Account for padding and border. We also might have to readjust the + // `bfc_relative_block_position` if it was different from the content size (i.e. was + // non-`auto` and/or was affected by min/max block size). + sequential_layout_state.advance_block_position( + (block_size - content_block_size) + pbm.padding.block_sum() + pbm.border.block_sum(), + ); + + sequential_layout_state.adjoin_assign(&CollapsedMargin::new(margin.block_end)); + } + + let content_rect = Rect { + start_corner: Vec2 { + block: pbm.padding.block_start + + pbm.border.block_start + + clearance.unwrap_or_else(Length::zero), + inline: pbm.padding.inline_start + pbm.border.inline_start + margin.inline_start, + }, + size: Vec2 { + block: block_size, + inline: containing_block_for_children.inline_size, + }, + }; + + let block_margins_collapsed_with_children = CollapsedBlockMargins::from_margin(&margin); + BoxFragment::new( + base_fragment_info, + style.clone(), + layout.fragments, content_rect, pbm.padding, pbm.border, @@ -915,6 +909,90 @@ fn layout_in_flow_replaced_block_level<'a>( ) } +struct ContainingBlockPaddingBorderAndMargin<'a> { + containing_block: ContainingBlock<'a>, + pbm: PaddingBorderMargin, + min_box_size: Vec2<Length>, + max_box_size: Vec2<Option<Length>>, + margin: Sides<Length>, +} + +/// Given the style for in in flow box and its containing block, determine the containing +/// block for its children and the margin it should use. +fn solve_containing_block_padding_border_and_margin_for_in_flow_box<'a>( + containing_block: &ContainingBlock<'_>, + style: &'a Arc<ComputedValues>, +) -> ContainingBlockPaddingBorderAndMargin<'a> { + let pbm = style.padding_border_margin(containing_block); + let box_size = style.content_box_size(containing_block, &pbm); + let max_box_size = style.content_max_box_size(containing_block, &pbm); + let min_box_size = style + .content_min_box_size(containing_block, &pbm) + .auto_is(Length::zero); + + let (mut inline_size, mut inline_margins) = + if let Some(inline_size) = box_size.inline.non_auto() { + ( + inline_size, + solve_inline_margins_for_in_flow_block_level(containing_block, &pbm, inline_size), + ) + } else { + let margin_inline_start = pbm.margin.inline_start.auto_is(Length::zero); + let margin_inline_end = pbm.margin.inline_end.auto_is(Length::zero); + let inline_size = containing_block.inline_size - + pbm.padding_border_sums.inline - + margin_inline_start - + margin_inline_end; + (inline_size, (margin_inline_start, margin_inline_end)) + }; + + // https://drafts.csswg.org/css2/visudet.html#min-max-widths + if let Some(max_inline_size) = max_box_size.inline { + if inline_size > max_inline_size { + inline_size = max_inline_size; + inline_margins = + solve_inline_margins_for_in_flow_block_level(containing_block, &pbm, inline_size); + } + } + + if inline_size < min_box_size.inline { + inline_size = min_box_size.inline; + inline_margins = + solve_inline_margins_for_in_flow_block_level(containing_block, &pbm, inline_size); + } + + let margin = Sides { + inline_start: inline_margins.0, + inline_end: inline_margins.1, + block_start: pbm.margin.block_start.auto_is(Length::zero), + block_end: pbm.margin.block_end.auto_is(Length::zero), + }; + + // https://drafts.csswg.org/css2/visudet.html#min-max-heights + let mut block_size = box_size.block; + if let LengthOrAuto::LengthPercentage(ref mut block_size) = block_size { + *block_size = block_size.clamp_between_extremums(min_box_size.block, max_box_size.block); + } + + let containing_block_for_children = ContainingBlock { + inline_size, + block_size, + style, + }; + // https://drafts.csswg.org/css-writing-modes/#orthogonal-flows + assert_eq!( + containing_block.style.writing_mode, containing_block_for_children.style.writing_mode, + "Mixed writing modes are not supported yet" + ); + ContainingBlockPaddingBorderAndMargin { + containing_block: containing_block_for_children, + pbm, + min_box_size, + max_box_size, + margin, + } +} + fn solve_inline_margins_for_in_flow_block_level( containing_block: &ContainingBlock, pbm: &PaddingBorderMargin, |