| // Copyright 2016 The Chromium Authors.All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "third_party/blink/renderer/core/layout/ng/ng_length_utils.h" |
| |
| #include <algorithm> |
| #include "base/optional.h" |
| #include "third_party/blink/renderer/core/layout/layout_box.h" |
| #include "third_party/blink/renderer/core/layout/layout_table_cell.h" |
| #include "third_party/blink/renderer/core/layout/ng/ng_block_node.h" |
| #include "third_party/blink/renderer/core/layout/ng/ng_constraint_space.h" |
| #include "third_party/blink/renderer/core/layout/ng/ng_constraint_space_builder.h" |
| #include "third_party/blink/renderer/core/layout/ng/ng_space_utils.h" |
| #include "third_party/blink/renderer/core/style/computed_style.h" |
| #include "third_party/blink/renderer/platform/geometry/layout_unit.h" |
| #include "third_party/blink/renderer/platform/geometry/length.h" |
| #include "third_party/blink/renderer/platform/geometry/length_functions.h" |
| |
| namespace blink { |
| |
| namespace { |
| |
| enum class EBlockAlignment { kStart, kCenter, kEnd }; |
| |
| inline EBlockAlignment BlockAlignment(const ComputedStyle& style, |
| const ComputedStyle& container_style) { |
| bool start_auto = style.MarginStartUsing(container_style).IsAuto(); |
| bool end_auto = style.MarginEndUsing(container_style).IsAuto(); |
| if (start_auto || end_auto) { |
| if (start_auto) |
| return end_auto ? EBlockAlignment::kCenter : EBlockAlignment::kEnd; |
| return EBlockAlignment::kStart; |
| } |
| |
| // If none of the inline margins are auto, look for -webkit- text-align |
| // values (which are really about block alignment). These are typically |
| // mapped from the legacy "align" HTML attribute. |
| switch (container_style.GetTextAlign()) { |
| case ETextAlign::kWebkitLeft: |
| if (container_style.IsLeftToRightDirection()) |
| return EBlockAlignment::kStart; |
| return EBlockAlignment::kEnd; |
| case ETextAlign::kWebkitRight: |
| if (container_style.IsLeftToRightDirection()) |
| return EBlockAlignment::kEnd; |
| return EBlockAlignment::kStart; |
| case ETextAlign::kWebkitCenter: |
| return EBlockAlignment::kCenter; |
| default: |
| return EBlockAlignment::kStart; |
| } |
| } |
| |
| } // anonymous namespace |
| |
| bool NeedMinMaxSizeForContentContribution(WritingMode mode, |
| const ComputedStyle& style) { |
| // During the intrinsic sizes pass percentages/calc() are defined to behave |
| // like 'auto'. As a result we need to calculate the intrinsic sizes for any |
| // children with percentages. E.g. |
| // <div style="float:left;"> |
| // <div style="width:30%;">text text</div> |
| // </div> |
| if (mode == WritingMode::kHorizontalTb) { |
| return style.Width().IsIntrinsicOrAuto() || |
| style.Width().IsPercentOrCalc() || style.MinWidth().IsIntrinsic() || |
| style.MaxWidth().IsIntrinsic(); |
| } |
| return style.Height().IsIntrinsicOrAuto() || |
| style.Height().IsPercentOrCalc() || style.MinHeight().IsIntrinsic() || |
| style.MaxHeight().IsIntrinsic(); |
| } |
| |
| // Check if we shouldn't resolve a percentage/calc()/-webkit-fill-available |
| // if we are in the intrinsic sizes phase. |
| bool InlineLengthUnresolvable(const Length& length, LengthResolvePhase phase) { |
| if (phase == LengthResolvePhase::kIntrinsic && |
| (length.IsPercentOrCalc() || length.IsFillAvailable())) |
| return true; |
| |
| return false; |
| } |
| |
| // When the containing block size to resolve against is indefinite, we |
| // cannot resolve percentages / calc() / -webkit-fill-available. |
| bool BlockLengthUnresolvable( |
| const NGConstraintSpace& constraint_space, |
| const Length& length, |
| LengthResolvePhase phase, |
| const LayoutUnit* opt_percentage_resolution_block_size_for_min_max) { |
| if (length.IsPercentOrCalc()) { |
| if (phase == LengthResolvePhase::kIntrinsic) |
| return true; |
| |
| LayoutUnit percentage_resolution_block_size = |
| opt_percentage_resolution_block_size_for_min_max |
| ? *opt_percentage_resolution_block_size_for_min_max |
| : constraint_space.PercentageResolutionBlockSize(); |
| return percentage_resolution_block_size == kIndefiniteSize; |
| } |
| |
| if (length.IsFillAvailable()) { |
| return phase == LengthResolvePhase::kIntrinsic || |
| constraint_space.AvailableSize().block_size == kIndefiniteSize; |
| } |
| |
| return false; |
| } |
| |
| LayoutUnit ResolveInlineLengthInternal( |
| const NGConstraintSpace& constraint_space, |
| const ComputedStyle& style, |
| const NGBoxStrut& border_padding, |
| const base::Optional<MinMaxSize>& min_and_max, |
| const Length& length) { |
| DCHECK_GE(constraint_space.AvailableSize().inline_size, LayoutUnit()); |
| DCHECK_GE(constraint_space.PercentageResolutionInlineSize(), LayoutUnit()); |
| DCHECK_EQ(constraint_space.GetWritingMode(), style.GetWritingMode()); |
| |
| switch (length.GetType()) { |
| case Length::kAuto: |
| case Length::kFillAvailable: { |
| LayoutUnit content_size = constraint_space.AvailableSize().inline_size; |
| NGBoxStrut margins = ComputeMarginsForSelf(constraint_space, style); |
| return std::max(border_padding.InlineSum(), |
| content_size - margins.InlineSum()); |
| } |
| case Length::kPercent: |
| case Length::kFixed: |
| case Length::kCalculated: { |
| LayoutUnit percentage_resolution_size = |
| constraint_space.PercentageResolutionInlineSize(); |
| LayoutUnit value = |
| MinimumValueForLength(length, percentage_resolution_size); |
| if (style.BoxSizing() == EBoxSizing::kContentBox) { |
| value += border_padding.InlineSum(); |
| } else { |
| value = std::max(border_padding.InlineSum(), value); |
| } |
| return value; |
| } |
| case Length::kMinContent: |
| case Length::kMaxContent: |
| case Length::kFitContent: { |
| DCHECK(min_and_max.has_value()); |
| LayoutUnit available_size = constraint_space.AvailableSize().inline_size; |
| LayoutUnit value; |
| if (length.IsMinContent()) { |
| value = min_and_max->min_size; |
| } else if (length.IsMaxContent() || available_size == LayoutUnit::Max()) { |
| // If the available space is infinite, fit-content resolves to |
| // max-content. See css-sizing section 2.1. |
| value = min_and_max->max_size; |
| } else { |
| NGBoxStrut margins = ComputeMarginsForSelf(constraint_space, style); |
| LayoutUnit fill_available = |
| std::max(LayoutUnit(), available_size - margins.InlineSum()); |
| value = min_and_max->ShrinkToFit(fill_available); |
| } |
| return value; |
| } |
| case Length::kDeviceWidth: |
| case Length::kDeviceHeight: |
| case Length::kExtendToZoom: |
| NOTREACHED() << "These should only be used for viewport definitions"; |
| FALLTHROUGH; |
| case Length::kMaxSizeNone: |
| default: |
| NOTREACHED(); |
| return border_padding.InlineSum(); |
| } |
| } |
| |
| LayoutUnit ResolveBlockLengthInternal( |
| const NGConstraintSpace& constraint_space, |
| const ComputedStyle& style, |
| const NGBoxStrut& border_padding, |
| const Length& length, |
| LayoutUnit content_size, |
| LengthResolvePhase phase, |
| const LayoutUnit* opt_percentage_resolution_block_size_for_min_max) { |
| DCHECK_EQ(constraint_space.GetWritingMode(), style.GetWritingMode()); |
| |
| switch (length.GetType()) { |
| case Length::kFillAvailable: { |
| LayoutUnit content_size = constraint_space.AvailableSize().block_size; |
| NGBoxStrut margins = ComputeMarginsForSelf(constraint_space, style); |
| return std::max(border_padding.BlockSum(), |
| content_size - margins.BlockSum()); |
| } |
| case Length::kPercent: |
| case Length::kFixed: |
| case Length::kCalculated: { |
| LayoutUnit percentage_resolution_block_size = |
| opt_percentage_resolution_block_size_for_min_max |
| ? *opt_percentage_resolution_block_size_for_min_max |
| : constraint_space.PercentageResolutionBlockSize(); |
| LayoutUnit value = |
| MinimumValueForLength(length, percentage_resolution_block_size); |
| |
| // Percentage-sized children of table cells, in the table "layout" phase, |
| // pretend they have box-sizing: border-box. |
| // TODO(crbug.com/285744): FF/Edge don't do this. Determine if there |
| // would be compat issues for matching their behavior. |
| if (style.BoxSizing() == EBoxSizing::kBorderBox || |
| (length.IsPercentOrCalc() && |
| constraint_space.TableCellChildLayoutMode() == |
| NGTableCellChildLayoutMode::kLayout)) { |
| value = std::max(border_padding.BlockSum(), value); |
| } else { |
| value += border_padding.BlockSum(); |
| } |
| return value; |
| } |
| case Length::kAuto: |
| case Length::kMinContent: |
| case Length::kMaxContent: |
| case Length::kFitContent: |
| #if DCHECK_IS_ON() |
| // Due to how content_size is calculated, it should always include border |
| // and padding. We cannot check for this if we are block-fragmented, |
| // though, because then the block-start border/padding may be in a |
| // different fragmentainer than the block-end border/padding. |
| if (content_size != LayoutUnit(-1) && |
| !constraint_space.HasBlockFragmentation()) |
| DCHECK_GE(content_size, border_padding.BlockSum()); |
| #endif // DCHECK_IS_ON() |
| return content_size; |
| case Length::kDeviceWidth: |
| case Length::kDeviceHeight: |
| case Length::kExtendToZoom: |
| NOTREACHED() << "These should only be used for viewport definitions"; |
| FALLTHROUGH; |
| case Length::kMaxSizeNone: |
| default: |
| NOTREACHED(); |
| return border_padding.BlockSum(); |
| } |
| } |
| |
| MinMaxSize ComputeMinAndMaxContentContribution( |
| WritingMode parent_writing_mode, |
| const ComputedStyle& style, |
| const NGBoxStrut& border_padding, |
| const base::Optional<MinMaxSize>& min_and_max) { |
| WritingMode child_writing_mode = style.GetWritingMode(); |
| |
| // Synthesize a zero-sized constraint space for resolving sizes against. |
| NGConstraintSpace space = |
| NGConstraintSpaceBuilder(child_writing_mode, child_writing_mode, |
| /* is_new_fc */ false) |
| .ToConstraintSpace(); |
| |
| LayoutUnit content_size = |
| min_and_max ? min_and_max->max_size : kIndefiniteSize; |
| |
| MinMaxSize computed_sizes; |
| const Length& inline_size = parent_writing_mode == WritingMode::kHorizontalTb |
| ? style.Width() |
| : style.Height(); |
| if (inline_size.IsAuto() || inline_size.IsPercentOrCalc() || |
| inline_size.IsFillAvailable() || inline_size.IsFitContent()) { |
| CHECK(min_and_max.has_value()); |
| computed_sizes = *min_and_max; |
| } else { |
| if (IsParallelWritingMode(parent_writing_mode, child_writing_mode)) { |
| computed_sizes = ResolveMainInlineLength(space, style, border_padding, |
| min_and_max, inline_size); |
| } else { |
| computed_sizes = |
| ResolveMainBlockLength(space, style, border_padding, inline_size, |
| content_size, LengthResolvePhase::kIntrinsic); |
| } |
| } |
| |
| const Length& max_length = parent_writing_mode == WritingMode::kHorizontalTb |
| ? style.MaxWidth() |
| : style.MaxHeight(); |
| LayoutUnit max; |
| if (IsParallelWritingMode(parent_writing_mode, child_writing_mode)) { |
| max = ResolveMaxInlineLength(space, style, border_padding, min_and_max, |
| max_length, LengthResolvePhase::kIntrinsic); |
| } else { |
| max = ResolveMaxBlockLength(space, style, border_padding, max_length, |
| content_size, LengthResolvePhase::kIntrinsic); |
| } |
| computed_sizes.Constrain(max); |
| |
| const Length& min_length = parent_writing_mode == WritingMode::kHorizontalTb |
| ? style.MinWidth() |
| : style.MinHeight(); |
| LayoutUnit min; |
| if (IsParallelWritingMode(parent_writing_mode, child_writing_mode)) { |
| min = ResolveMinInlineLength(space, style, border_padding, min_and_max, |
| min_length, LengthResolvePhase::kIntrinsic); |
| } else { |
| min = ResolveMinBlockLength(space, style, border_padding, min_length, |
| content_size, LengthResolvePhase::kIntrinsic); |
| } |
| computed_sizes.Encompass(min); |
| |
| return computed_sizes; |
| } |
| |
| MinMaxSize ComputeMinAndMaxContentContribution( |
| const ComputedStyle& parent_style, |
| NGLayoutInputNode child, |
| const MinMaxSizeInput& input) { |
| const ComputedStyle& child_style = child.Style(); |
| WritingMode parent_writing_mode = parent_style.GetWritingMode(); |
| WritingMode child_writing_mode = child_style.GetWritingMode(); |
| LayoutBox* box = child.GetLayoutBox(); |
| |
| if (box->NeedsPreferredWidthsRecalculation()) { |
| // Some objects (when there's an intrinsic ratio) have their min/max inline |
| // size affected by the block size of their container. We don't really know |
| // whether the containing block of this child did change or is going to |
| // change size. However, this is our only opportunity to make sure that it |
| // gets its min/max widths calculated. |
| box->SetPreferredLogicalWidthsDirty(); |
| } |
| |
| if (IsParallelWritingMode(parent_writing_mode, child_writing_mode)) { |
| if (!box->PreferredLogicalWidthsDirty()) { |
| return {box->MinPreferredLogicalWidth(), box->MaxPreferredLogicalWidth()}; |
| } |
| // Tables are special; even if a width is specified, they may end up being |
| // sized different. So we just always let the table code handle this. |
| // Replaced elements may size themselves using aspect ratios and block |
| // sizes, so we pass that on as well. |
| if (box->IsTable() || box->IsTablePart() || box->IsLayoutReplaced()) { |
| bool needs_size_reset = false; |
| if (!box->HasOverrideContainingBlockContentLogicalHeight()) { |
| box->SetOverrideContainingBlockContentLogicalHeight( |
| input.percentage_resolution_block_size); |
| needs_size_reset = true; |
| } |
| MinMaxSize result{box->MinPreferredLogicalWidth(), |
| box->MaxPreferredLogicalWidth()}; |
| if (needs_size_reset) |
| box->ClearOverrideContainingBlockContentSize(); |
| return result; |
| } |
| } |
| |
| base::Optional<MinMaxSize> minmax; |
| if (NeedMinMaxSizeForContentContribution(parent_writing_mode, child_style)) { |
| // We need to set up a constraint space with correct fallback available |
| // inline size in case of orthogonal children. |
| NGConstraintSpace indefinite_constraint_space; |
| const NGConstraintSpace* child_constraint_space = nullptr; |
| if (!IsParallelWritingMode(parent_writing_mode, child_writing_mode)) { |
| indefinite_constraint_space = |
| CreateIndefiniteConstraintSpaceForChild(parent_style, child); |
| child_constraint_space = &indefinite_constraint_space; |
| } |
| minmax = child.ComputeMinMaxSize(parent_writing_mode, input, |
| child_constraint_space); |
| } |
| // Synthesize a zero-sized constraint space for determining the borders, and |
| // padding. |
| NGConstraintSpace space = |
| NGConstraintSpaceBuilder(child_writing_mode, child_writing_mode, |
| /* is_new_fc */ false) |
| .ToConstraintSpace(); |
| NGBoxStrut border_padding = |
| ComputeBorders(space, child) + ComputePadding(space, child_style); |
| |
| MinMaxSize sizes = ComputeMinAndMaxContentContribution( |
| parent_writing_mode, child_style, border_padding, minmax); |
| if (IsParallelWritingMode(parent_writing_mode, child_writing_mode)) |
| box->SetPreferredLogicalWidthsFromNG(sizes); |
| return sizes; |
| } |
| |
| MinMaxSize ComputeMinAndMaxContentSizeForOutOfFlow( |
| const NGConstraintSpace& constraint_space, |
| NGLayoutInputNode node, |
| const NGBoxStrut& border_padding, |
| const MinMaxSizeInput& input) { |
| LayoutBox* box = node.GetLayoutBox(); |
| // If we've already populated the legacy preferred logical widths cache for |
| // this node at the bottom of this function, use those cached results here. |
| // Or, if we're working on a table, use the legacy preferred widths code |
| // instead of ComputeMinAndMaxContentContribution below because |
| // ComputeMinAndMaxContentContribution assumes that if an element has a |
| // specified size, that's its final size, which tables don't follow. |
| if ((!box->PreferredLogicalWidthsDirty() && |
| !box->NeedsPreferredWidthsRecalculation()) || |
| box->IsTable()) { |
| return MinMaxSize{box->MinPreferredLogicalWidth(), |
| box->MaxPreferredLogicalWidth()}; |
| } |
| |
| // Compute the intrinsic sizes without regard to the specified sizes. |
| MinMaxSize result = node.ComputeMinMaxSize(node.Style().GetWritingMode(), |
| input, &constraint_space); |
| // Apply the specified min, main, max sizes. |
| MinMaxSize contribution = ComputeMinAndMaxContentContribution( |
| node.Style().GetWritingMode(), node.Style(), border_padding, result); |
| // Cache these computed values. |
| box->SetPreferredLogicalWidthsFromNG(contribution); |
| return result; |
| } |
| |
| LayoutUnit ComputeInlineSizeForFragment( |
| const NGConstraintSpace& space, |
| NGLayoutInputNode node, |
| const NGBoxStrut& border_padding, |
| const MinMaxSize* override_minmax_for_test) { |
| if (space.IsFixedInlineSize() || space.IsAnonymous()) |
| return space.AvailableSize().inline_size; |
| |
| const ComputedStyle& style = node.Style(); |
| Length logical_width = style.LogicalWidth(); |
| if (logical_width.IsAuto() && space.IsShrinkToFit()) |
| logical_width = Length::FitContent(); |
| |
| LayoutBox* box = node.GetLayoutBox(); |
| // If we have usable cached min/max intrinsic sizes, use those if we can. They |
| // will normally also be constrained to {min,max}-inline-size, but not if |
| // percentages are involved. In such cases we'll have to calculate and apply |
| // the constraints on our own. We also need to discard the cached values if |
| // the box has certain properties (e.g. percentage padding) that cause the |
| // cached values to be affected by extrinsic sizing. |
| if (!box->PreferredLogicalWidthsDirty() && !override_minmax_for_test && |
| !style.LogicalMinWidth().IsPercentOrCalc() && |
| !style.LogicalMaxWidth().IsPercentOrCalc() && |
| !box->NeedsPreferredWidthsRecalculation()) { |
| if (logical_width.IsFitContent()) { |
| // This is not as easy as {min, max}.ShrinkToFit() because we also need |
| // to subtract inline margins from the available size. The code in |
| // ResolveMainInlineLength knows how to handle that, just call that. |
| |
| MinMaxSize min_and_max = {box->MinPreferredLogicalWidth(), |
| box->MaxPreferredLogicalWidth()}; |
| return ResolveMainInlineLength(space, style, border_padding, min_and_max, |
| logical_width); |
| } |
| if (logical_width.IsMinContent()) |
| return box->MinPreferredLogicalWidth(); |
| if (logical_width.IsMaxContent()) |
| return box->MaxPreferredLogicalWidth(); |
| } |
| |
| base::Optional<MinMaxSize> min_and_max; |
| if (NeedMinMaxSize(space, style)) { |
| if (override_minmax_for_test) { |
| min_and_max = *override_minmax_for_test; |
| } else { |
| min_and_max = node.ComputeMinMaxSize( |
| space.GetWritingMode(), |
| MinMaxSizeInput(space.PercentageResolutionBlockSize()), &space); |
| // Cache these computed values |
| MinMaxSize contribution = ComputeMinAndMaxContentContribution( |
| style.GetWritingMode(), style, border_padding, min_and_max); |
| box->SetPreferredLogicalWidthsFromNG(contribution); |
| } |
| } |
| |
| LayoutUnit extent = ResolveMainInlineLength(space, style, border_padding, |
| min_and_max, logical_width); |
| |
| LayoutUnit max = ResolveMaxInlineLength(space, style, border_padding, |
| min_and_max, style.LogicalMaxWidth(), |
| LengthResolvePhase::kLayout); |
| LayoutUnit min = ResolveMinInlineLength(space, style, border_padding, |
| min_and_max, style.LogicalMinWidth(), |
| LengthResolvePhase::kLayout); |
| return ConstrainByMinMax(extent, min, max); |
| } |
| |
| namespace { |
| |
| // Computes the block-size for a fragment, ignoring the fixed block-size if set. |
| LayoutUnit ComputeBlockSizeForFragmentInternal( |
| const NGConstraintSpace& constraint_space, |
| const ComputedStyle& style, |
| const NGBoxStrut& border_padding, |
| LayoutUnit content_size, |
| const LayoutUnit* opt_percentage_resolution_block_size_for_min_max = |
| nullptr) { |
| LayoutUnit min = ResolveMinBlockLength( |
| constraint_space, style, border_padding, style.LogicalMinHeight(), |
| content_size, LengthResolvePhase::kLayout, |
| opt_percentage_resolution_block_size_for_min_max); |
| const Length& logical_height = style.LogicalHeight(); |
| // Scrollable percentage-sized children of table cells, in the table |
| // "measure" phase contribute nothing to the row height measurement. |
| // See: https://drafts.csswg.org/css-tables-3/#row-layout |
| // We only apply this rule if the block size of the containing table cell is |
| // considered to be restricted, though. Otherwise, especially if this is the |
| // only child of the cell, and that is the only cell in the row, we'd end up |
| // with zero block size. To match the legacy layout engine behavior in |
| // LayoutBox::ContainingBlockLogicalHeightForPercentageResolution(), we only |
| // check the block-size of the containing cell and its containing table. Other |
| // things to consider, would be checking the row and row-group, and also other |
| // properties, such as {min,max}-block-size. |
| if (logical_height.IsPercentOrCalc() && |
| constraint_space.TableCellChildLayoutMode() == |
| NGTableCellChildLayoutMode::kMeasureRestricted && |
| (style.OverflowY() == EOverflow::kAuto || |
| style.OverflowY() == EOverflow::kScroll)) |
| return min; |
| |
| LayoutUnit extent = ResolveMainBlockLength( |
| constraint_space, style, border_padding, logical_height, content_size, |
| LengthResolvePhase::kLayout, |
| opt_percentage_resolution_block_size_for_min_max); |
| if (extent == kIndefiniteSize) { |
| DCHECK_EQ(content_size, kIndefiniteSize); |
| return extent; |
| } |
| |
| LayoutUnit max = ResolveMaxBlockLength( |
| constraint_space, style, border_padding, style.LogicalMaxHeight(), |
| content_size, LengthResolvePhase::kLayout, |
| opt_percentage_resolution_block_size_for_min_max); |
| |
| return ConstrainByMinMax(extent, min, max); |
| } |
| |
| } // namespace |
| |
| LayoutUnit ComputeBlockSizeForFragment( |
| const NGConstraintSpace& constraint_space, |
| const ComputedStyle& style, |
| const NGBoxStrut& border_padding, |
| LayoutUnit content_size) { |
| // The final block-size of a table-cell is always its intrinsic size. |
| if (constraint_space.IsTableCell() && content_size != kIndefiniteSize) |
| return content_size; |
| |
| if (constraint_space.IsFixedBlockSize()) |
| return constraint_space.AvailableSize().block_size; |
| |
| if (constraint_space.IsAnonymous()) |
| return content_size; |
| |
| return ComputeBlockSizeForFragmentInternal(constraint_space, style, |
| border_padding, content_size); |
| } |
| |
| // Computes size for a replaced element. |
| LogicalSize ComputeReplacedSize( |
| const NGLayoutInputNode& node, |
| const NGConstraintSpace& space, |
| const base::Optional<MinMaxSize>& child_minmax) { |
| DCHECK(node.IsReplaced()); |
| const ComputedStyle& style = node.Style(); |
| |
| NGBoxStrut border_padding = |
| ComputeBorders(space, node) + ComputePadding(space, style); |
| LayoutUnit inline_min = ResolveMinInlineLength( |
| space, style, border_padding, child_minmax, style.LogicalMinWidth(), |
| LengthResolvePhase::kLayout); |
| LayoutUnit inline_max = ResolveMaxInlineLength( |
| space, style, border_padding, child_minmax, style.LogicalMaxWidth(), |
| LengthResolvePhase::kLayout); |
| LayoutUnit block_min = ResolveMinBlockLength( |
| space, style, border_padding, style.LogicalMinHeight(), |
| border_padding.BlockSum(), LengthResolvePhase::kLayout); |
| LayoutUnit block_max = ResolveMaxBlockLength( |
| space, style, border_padding, style.LogicalMaxHeight(), LayoutUnit::Max(), |
| LengthResolvePhase::kLayout); |
| |
| const Length& inline_length = style.LogicalWidth(); |
| const Length& block_length = style.LogicalHeight(); |
| base::Optional<LayoutUnit> replaced_inline; |
| if (!inline_length.IsAuto()) { |
| replaced_inline = ResolveMainInlineLength(space, style, border_padding, |
| child_minmax, inline_length); |
| replaced_inline = |
| ConstrainByMinMax(*replaced_inline, inline_min, inline_max); |
| } |
| base::Optional<LayoutUnit> replaced_block; |
| if (!block_length.IsAuto()) { |
| replaced_block = ResolveMainBlockLength( |
| space, style, border_padding, block_length, |
| space.AvailableSize().block_size, LengthResolvePhase::kLayout); |
| replaced_block = ConstrainByMinMax(*replaced_block, block_min, block_max); |
| } |
| if (replaced_inline && replaced_block) |
| return LogicalSize(*replaced_inline, *replaced_block); |
| |
| base::Optional<LayoutUnit> intrinsic_inline; |
| base::Optional<LayoutUnit> intrinsic_block; |
| LogicalSize aspect_ratio; |
| |
| node.IntrinsicSize(&intrinsic_inline, &intrinsic_block, &aspect_ratio); |
| // Computing intrinsic size is complicated by the fact that |
| // intrinsic_inline, intrinsic_block, and aspect_ratio can all |
| // be empty independent of each other. |
| // https://www.w3.org/TR/CSS22/visudet.html#inline-replaced-width |
| if (intrinsic_inline) |
| intrinsic_inline = *intrinsic_inline + border_padding.InlineSum(); |
| else if (aspect_ratio.IsEmpty()) |
| intrinsic_inline = LayoutUnit(300) + border_padding.InlineSum(); |
| if (intrinsic_block) |
| intrinsic_block = *intrinsic_block + border_padding.BlockSum(); |
| else if (aspect_ratio.IsEmpty()) |
| intrinsic_block = LayoutUnit(150) + border_padding.BlockSum(); |
| if (!intrinsic_inline) { |
| if (intrinsic_block) { |
| intrinsic_inline = ((*intrinsic_block - border_padding.BlockSum()) * |
| aspect_ratio.inline_size / aspect_ratio.block_size) + |
| border_padding.InlineSum(); |
| } else { |
| intrinsic_inline = space.AvailableSize().inline_size; |
| } |
| } |
| if (!intrinsic_block) { |
| intrinsic_block = ((*intrinsic_inline - border_padding.InlineSum()) * |
| aspect_ratio.block_size / aspect_ratio.inline_size) + |
| border_padding.BlockSum(); |
| } |
| // At this point, both intrinsic_inline and intrinsic_block have value. |
| // If we only know one length, the other length gets computed wrt one we know. |
| auto ComputeBlockFromInline = [&replaced_inline, &aspect_ratio, |
| &border_padding](LayoutUnit default_block) { |
| DCHECK(default_block >= border_padding.BlockSum()); |
| if (aspect_ratio.IsEmpty()) |
| return default_block; |
| return ((*replaced_inline - border_padding.InlineSum()) * |
| aspect_ratio.block_size / aspect_ratio.inline_size) + |
| border_padding.BlockSum(); |
| }; |
| |
| auto ComputeInlineFromBlock = [&replaced_block, &aspect_ratio, |
| &border_padding](LayoutUnit default_inline) { |
| DCHECK(default_inline >= border_padding.InlineSum()); |
| if (aspect_ratio.IsEmpty()) |
| return default_inline; |
| return ((*replaced_block - border_padding.BlockSum()) * |
| aspect_ratio.inline_size / aspect_ratio.block_size) + |
| border_padding.InlineSum(); |
| }; |
| if (replaced_inline) { |
| DCHECK(!replaced_block); |
| replaced_block = ComputeBlockFromInline(*intrinsic_block); |
| replaced_block = ConstrainByMinMax(*replaced_block, block_min, block_max); |
| } else if (replaced_block) { |
| DCHECK(!replaced_inline); |
| replaced_inline = ComputeInlineFromBlock(*intrinsic_inline); |
| replaced_inline = |
| ConstrainByMinMax(*replaced_inline, inline_min, inline_max); |
| } else { |
| // If both lengths are unknown, they get defined by intrinsic values. |
| DCHECK(!replaced_inline); |
| DCHECK(!replaced_block); |
| replaced_inline = *intrinsic_inline; |
| replaced_block = *intrinsic_block; |
| // If lengths are constrained, keep aspect ratio. |
| // The side that shrank the most defines the other side. |
| LayoutUnit constrained_inline = |
| ConstrainByMinMax(*replaced_inline, inline_min, inline_max); |
| LayoutUnit constrained_block = |
| ConstrainByMinMax(*replaced_block, block_min, block_max); |
| if (constrained_inline != replaced_inline || |
| constrained_block != replaced_block) { |
| LayoutUnit inline_ratio = |
| (*replaced_inline - border_padding.InlineSum()) == LayoutUnit() |
| ? LayoutUnit::Max() |
| : (constrained_inline - border_padding.InlineSum()) / |
| (*replaced_inline - border_padding.InlineSum()); |
| LayoutUnit block_ratio = |
| (*replaced_block - border_padding.BlockSum()) == LayoutUnit() |
| ? LayoutUnit::Max() |
| : (constrained_block - border_padding.BlockSum()) / |
| (*replaced_block - border_padding.BlockSum()); |
| |
| // The following implements spec table from section 10.4 at |
| // https://www.w3.org/TR/CSS22/visudet.html#min-max-widths |
| // Translating specs to code: |
| // inline_ratio < 1 => w > max_width |
| // inline_ratio > 1 => w < min_width |
| // block_ratio < 1 => h > max_height |
| // block_ratio > 1 => h < min_height |
| LayoutUnit one_unit(1); |
| if (inline_ratio != one_unit || block_ratio != one_unit) { |
| if ((inline_ratio < one_unit && block_ratio > one_unit) || |
| (inline_ratio > one_unit && block_ratio < one_unit)) { |
| // Constraints caused us to grow in one dimension and shrink in the |
| // other. Use both constrained sizes. |
| replaced_inline = constrained_inline; |
| replaced_block = constrained_block; |
| } else if (block_ratio == one_unit || |
| (inline_ratio < one_unit && inline_ratio <= block_ratio) || |
| (inline_ratio > one_unit && inline_ratio >= block_ratio)) { |
| // The inline size got constrained more extremely than the block size. |
| // Use constrained inline size, re-calculate block size from aspect |
| // ratio. |
| replaced_inline = constrained_inline; |
| replaced_block = ComputeBlockFromInline(constrained_block); |
| } else { |
| // The block size got constrained more extremely than the inline size. |
| // Use constrained block size, re-calculate inline size from aspect |
| // ratio. |
| replaced_block = constrained_block; |
| replaced_inline = ComputeInlineFromBlock(constrained_inline); |
| } |
| } |
| } |
| } |
| return LogicalSize(*replaced_inline, *replaced_block); |
| } |
| |
| int ResolveUsedColumnCount(int computed_count, |
| LayoutUnit computed_size, |
| LayoutUnit used_gap, |
| LayoutUnit available_size) { |
| if (computed_size == kIndefiniteSize) { |
| DCHECK(computed_count); |
| return computed_count; |
| } |
| DCHECK_GT(computed_size, LayoutUnit()); |
| int count_from_width = |
| ((available_size + used_gap) / (computed_size + used_gap)).ToInt(); |
| count_from_width = std::max(1, count_from_width); |
| if (!computed_count) |
| return count_from_width; |
| return std::max(1, std::min(computed_count, count_from_width)); |
| } |
| |
| int ResolveUsedColumnCount(LayoutUnit available_size, |
| const ComputedStyle& style) { |
| LayoutUnit computed_column_inline_size = |
| style.HasAutoColumnWidth() |
| ? kIndefiniteSize |
| : std::max(LayoutUnit(1), LayoutUnit(style.ColumnWidth())); |
| LayoutUnit gap = ResolveUsedColumnGap(available_size, style); |
| int computed_count = style.ColumnCount(); |
| return ResolveUsedColumnCount(computed_count, computed_column_inline_size, |
| gap, available_size); |
| } |
| |
| LayoutUnit ResolveUsedColumnInlineSize(int computed_count, |
| LayoutUnit computed_size, |
| LayoutUnit used_gap, |
| LayoutUnit available_size) { |
| int used_count = ResolveUsedColumnCount(computed_count, computed_size, |
| used_gap, available_size); |
| return std::max(((available_size + used_gap) / used_count) - used_gap, |
| LayoutUnit()); |
| } |
| |
| LayoutUnit ResolveUsedColumnInlineSize(LayoutUnit available_size, |
| const ComputedStyle& style) { |
| // Should only attempt to resolve this if columns != auto. |
| DCHECK(!style.HasAutoColumnCount() || !style.HasAutoColumnWidth()); |
| |
| LayoutUnit computed_size = |
| style.HasAutoColumnWidth() |
| ? kIndefiniteSize |
| : std::max(LayoutUnit(1), LayoutUnit(style.ColumnWidth())); |
| int computed_count = style.HasAutoColumnCount() ? 0 : style.ColumnCount(); |
| LayoutUnit used_gap = ResolveUsedColumnGap(available_size, style); |
| return ResolveUsedColumnInlineSize(computed_count, computed_size, used_gap, |
| available_size); |
| } |
| |
| LayoutUnit ResolveUsedColumnGap(LayoutUnit available_size, |
| const ComputedStyle& style) { |
| if (style.ColumnGap().IsNormal()) |
| return LayoutUnit(style.GetFontDescription().ComputedPixelSize()); |
| return ValueForLength(style.ColumnGap().GetLength(), available_size); |
| } |
| |
| NGPhysicalBoxStrut ComputePhysicalMargins( |
| const ComputedStyle& style, |
| LayoutUnit percentage_resolution_size) { |
| if (!style.MayHaveMargin()) |
| return NGPhysicalBoxStrut(); |
| |
| return { |
| MinimumValueForLength(style.MarginTop(), percentage_resolution_size), |
| MinimumValueForLength(style.MarginRight(), percentage_resolution_size), |
| MinimumValueForLength(style.MarginBottom(), percentage_resolution_size), |
| MinimumValueForLength(style.MarginLeft(), percentage_resolution_size)}; |
| } |
| |
| NGBoxStrut ComputeMarginsFor(const NGConstraintSpace& constraint_space, |
| const ComputedStyle& style, |
| const NGConstraintSpace& compute_for) { |
| if (!style.MayHaveMargin() || constraint_space.IsAnonymous()) |
| return NGBoxStrut(); |
| LayoutUnit percentage_resolution_size = |
| constraint_space.PercentageResolutionInlineSizeForParentWritingMode(); |
| return ComputePhysicalMargins(style, percentage_resolution_size) |
| .ConvertToLogical(compute_for.GetWritingMode(), compute_for.Direction()); |
| } |
| |
| NGBoxStrut ComputeMinMaxMargins(const ComputedStyle& parent_style, |
| NGLayoutInputNode child) { |
| // An inline child just produces line-boxes which don't have any margins. |
| if (child.IsInline() || !child.Style().MayHaveMargin()) |
| return NGBoxStrut(); |
| |
| const Length& inline_start_margin_length = |
| child.Style().MarginStartUsing(parent_style); |
| const Length& inline_end_margin_length = |
| child.Style().MarginEndUsing(parent_style); |
| |
| // TODO(ikilpatrick): We may want to re-visit calculated margins at some |
| // point. Currently "margin-left: calc(10px + 50%)" will resolve to 0px, but |
| // 10px would be more correct, (as percentages resolve to zero). |
| NGBoxStrut margins; |
| if (inline_start_margin_length.IsFixed()) |
| margins.inline_start = LayoutUnit(inline_start_margin_length.Value()); |
| if (inline_end_margin_length.IsFixed()) |
| margins.inline_end = LayoutUnit(inline_end_margin_length.Value()); |
| |
| return margins; |
| } |
| |
| namespace { |
| |
| NGBoxStrut ComputeBordersInternal(const ComputedStyle& style) { |
| NGBoxStrut borders; |
| borders.inline_start = LayoutUnit(style.BorderStartWidth()); |
| borders.inline_end = LayoutUnit(style.BorderEndWidth()); |
| borders.block_start = LayoutUnit(style.BorderBeforeWidth()); |
| borders.block_end = LayoutUnit(style.BorderAfterWidth()); |
| return borders; |
| } |
| |
| } // namespace |
| |
| NGBoxStrut ComputeBorders(const NGConstraintSpace& constraint_space, |
| const NGLayoutInputNode node) { |
| // If we are producing an anonymous fragment (e.g. a column), it has no |
| // borders, padding or scrollbars. Using the ones from the container can only |
| // cause trouble. |
| if (constraint_space.IsAnonymous()) |
| return NGBoxStrut(); |
| |
| // If we are a table cell we just access the values set by the parent table |
| // layout as border may be collapsed etc. |
| if (constraint_space.IsTableCell()) |
| return constraint_space.TableCellBorders(); |
| |
| return ComputeBordersInternal(node.Style()); |
| } |
| |
| NGBoxStrut ComputeBordersForInline(const ComputedStyle& style) { |
| return ComputeBordersInternal(style); |
| } |
| |
| NGBoxStrut ComputeBordersForTest(const ComputedStyle& style) { |
| return ComputeBordersInternal(style); |
| } |
| |
| NGBoxStrut ComputeIntrinsicPadding(const NGConstraintSpace& constraint_space, |
| const ComputedStyle& style, |
| const NGBoxStrut& scrollbar) { |
| DCHECK(constraint_space.IsTableCell()); |
| DCHECK(!scrollbar.block_start); |
| |
| // During the "layout" table phase, adjust the given intrinsic-padding to |
| // accommodate the scrollbar. |
| NGBoxStrut intrinsic_padding = constraint_space.TableCellIntrinsicPadding(); |
| if (constraint_space.IsFixedBlockSize()) { |
| if (style.VerticalAlign() == EVerticalAlign::kMiddle) { |
| intrinsic_padding.block_start -= scrollbar.block_end / 2; |
| intrinsic_padding.block_end -= scrollbar.block_end / 2; |
| } else { |
| intrinsic_padding.block_end -= scrollbar.block_end; |
| } |
| } |
| |
| return intrinsic_padding; |
| } |
| |
| NGBoxStrut ComputePadding(const NGConstraintSpace& constraint_space, |
| const ComputedStyle& style) { |
| // If we are producing an anonymous fragment (e.g. a column) we shouldn't |
| // have any padding. |
| if (!style.MayHavePadding() || constraint_space.IsAnonymous()) |
| return NGBoxStrut(); |
| |
| LayoutUnit percentage_resolution_size = |
| constraint_space.PercentageResolutionInlineSizeForParentWritingMode(); |
| NGBoxStrut padding = { |
| MinimumValueForLength(style.PaddingStart(), percentage_resolution_size), |
| MinimumValueForLength(style.PaddingEnd(), percentage_resolution_size), |
| MinimumValueForLength(style.PaddingBefore(), percentage_resolution_size), |
| MinimumValueForLength(style.PaddingAfter(), percentage_resolution_size)}; |
| |
| if (style.Display() == EDisplay::kTableCell) { |
| // Compatibility hack to mach legacy layout. Legacy layout floors padding on |
| // the block sides, but not on the inline sides. o.O |
| padding.block_start = LayoutUnit(padding.block_start.Floor()); |
| padding.block_end = LayoutUnit(padding.block_end.Floor()); |
| } |
| |
| return padding; |
| } |
| |
| NGBoxStrut ComputeScrollbars(const NGConstraintSpace& constraint_space, |
| const NGLayoutInputNode node) { |
| const ComputedStyle& style = node.Style(); |
| if (constraint_space.IsAnonymous() || style.IsOverflowVisible()) |
| return NGBoxStrut(); |
| NGPhysicalBoxStrut sizes; |
| const LayoutBox* layout_box = node.GetLayoutBox(); |
| LayoutUnit horizontal = LayoutUnit(layout_box->HorizontalScrollbarHeight()); |
| sizes.bottom = horizontal; |
| LayoutUnit vertical = LayoutUnit(layout_box->VerticalScrollbarWidth()); |
| if (layout_box->ShouldPlaceBlockDirectionScrollbarOnLogicalLeft()) |
| sizes.left = vertical; |
| else |
| sizes.right = vertical; |
| return sizes.ConvertToLogical(style.GetWritingMode(), style.Direction()); |
| } |
| |
| bool NeedsInlineSizeToResolveLineLeft(const ComputedStyle& style, |
| const ComputedStyle& container_style) { |
| // In RTL, there's no block alignment where we can guarantee that line-left |
| // doesn't depend on the inline size of a fragment. |
| if (IsRtl(container_style.Direction())) |
| return true; |
| |
| return BlockAlignment(style, container_style) != EBlockAlignment::kStart; |
| } |
| |
| void ResolveInlineMargins(const ComputedStyle& style, |
| const ComputedStyle& container_style, |
| LayoutUnit available_inline_size, |
| LayoutUnit inline_size, |
| NGBoxStrut* margins) { |
| DCHECK(margins) << "Margins cannot be NULL here"; |
| const LayoutUnit used_space = inline_size + margins->InlineSum(); |
| const LayoutUnit available_space = available_inline_size - used_space; |
| if (available_space > LayoutUnit()) { |
| EBlockAlignment alignment = BlockAlignment(style, container_style); |
| if (alignment == EBlockAlignment::kCenter) |
| margins->inline_start += available_space / 2; |
| else if (alignment == EBlockAlignment::kEnd) |
| margins->inline_start += available_space; |
| } |
| margins->inline_end = |
| available_inline_size - inline_size - margins->inline_start; |
| } |
| |
| LayoutUnit LineOffsetForTextAlign(ETextAlign text_align, |
| TextDirection direction, |
| LayoutUnit space_left) { |
| bool is_ltr = IsLtr(direction); |
| if (text_align == ETextAlign::kStart || text_align == ETextAlign::kJustify) |
| text_align = is_ltr ? ETextAlign::kLeft : ETextAlign::kRight; |
| else if (text_align == ETextAlign::kEnd) |
| text_align = is_ltr ? ETextAlign::kRight : ETextAlign::kLeft; |
| |
| switch (text_align) { |
| case ETextAlign::kLeft: |
| case ETextAlign::kWebkitLeft: { |
| // The direction of the block should determine what happens with wide |
| // lines. In particular with RTL blocks, wide lines should still spill |
| // out to the left. |
| if (is_ltr) |
| return LayoutUnit(); |
| return space_left.ClampPositiveToZero(); |
| } |
| case ETextAlign::kRight: |
| case ETextAlign::kWebkitRight: { |
| // In RTL, trailing spaces appear on the left of the line. |
| if (UNLIKELY(!is_ltr)) |
| return space_left; |
| // Wide lines spill out of the block based off direction. |
| // So even if text-align is right, if direction is LTR, wide lines |
| // should overflow out of the right side of the block. |
| if (space_left > LayoutUnit()) |
| return space_left; |
| return LayoutUnit(); |
| } |
| case ETextAlign::kCenter: |
| case ETextAlign::kWebkitCenter: { |
| if (is_ltr) |
| return (space_left / 2).ClampNegativeToZero(); |
| // In RTL, trailing spaces appear on the left of the line. |
| if (space_left > LayoutUnit()) |
| return (space_left / 2).ClampNegativeToZero(); |
| // In RTL, wide lines should spill out to the left, same as kRight. |
| return space_left; |
| } |
| default: |
| NOTREACHED(); |
| return LayoutUnit(); |
| } |
| } |
| |
| namespace { |
| |
| // Calculates default content size for html and body elements in quirks mode. |
| // Returns |kIndefiniteSize| in all other cases. |
| LayoutUnit CalculateDefaultBlockSize( |
| const NGConstraintSpace& space, |
| const NGBlockNode& node, |
| const NGBoxStrut& border_scrollbar_padding) { |
| // In quirks mode, html and body elements will completely fill the ICB, block |
| // percentages should resolve against this size. |
| if (node.IsQuirkyAndFillsViewport()) { |
| LayoutUnit block_size = space.AvailableSize().block_size; |
| block_size -= ComputeMarginsForSelf(space, node.Style()).BlockSum(); |
| return std::max(block_size.ClampNegativeToZero(), |
| border_scrollbar_padding.BlockSum()); |
| } |
| return kIndefiniteSize; |
| } |
| |
| // Clamp the inline size of the scrollbar, unless it's larger than the inline |
| // size of the content box, in which case we'll return that instead. Scrollbar |
| // handling is quite bad in such situations, and this method here is just to |
| // make sure that left-hand scrollbars don't mess up scrollWidth. For the full |
| // story, visit http://crbug.com/724255. |
| bool ClampScrollbarToContentBox(NGBoxStrut* scrollbars, |
| LayoutUnit content_box_inline_size) { |
| DCHECK(scrollbars->InlineSum()); |
| if (scrollbars->InlineSum() <= content_box_inline_size) |
| return false; |
| if (scrollbars->inline_end) { |
| DCHECK(!scrollbars->inline_start); |
| scrollbars->inline_end = content_box_inline_size; |
| } else { |
| DCHECK(scrollbars->inline_start); |
| scrollbars->inline_start = content_box_inline_size; |
| } |
| return true; |
| } |
| |
| } // namespace |
| |
| NGFragmentGeometry CalculateInitialFragmentGeometry( |
| const NGConstraintSpace& constraint_space, |
| const NGBlockNode& node) { |
| const ComputedStyle& style = node.Style(); |
| |
| NGBoxStrut border = ComputeBorders(constraint_space, node); |
| NGBoxStrut padding = ComputePadding(constraint_space, style); |
| NGBoxStrut scrollbar = ComputeScrollbars(constraint_space, node); |
| NGBoxStrut border_padding = border + padding; |
| NGBoxStrut border_scrollbar_padding = border_padding + scrollbar; |
| |
| // If we have a percentage size, we need to set the |
| // HasPercentHeightDescendants flag correctly so that flexbox knows it may |
| // need to redo layout and can also do some performance optimizations. |
| if (style.LogicalHeight().IsPercentOrCalc() || |
| style.LogicalMinHeight().IsPercentOrCalc() || |
| style.LogicalMaxHeight().IsPercentOrCalc() || |
| (node.IsFlexItem() && style.FlexBasis().IsPercentOrCalc())) { |
| // This call has the side-effect of setting HasPercentHeightDescendants |
| // correctly. |
| node.GetLayoutBox()->ComputePercentageLogicalHeight(Length::Percent(0)); |
| } |
| |
| LayoutUnit default_block_size = CalculateDefaultBlockSize( |
| constraint_space, node, border_scrollbar_padding); |
| LogicalSize border_box_size( |
| ComputeInlineSizeForFragment(constraint_space, node, border_padding), |
| ComputeBlockSizeForFragment(constraint_space, style, border_padding, |
| default_block_size)); |
| |
| if (UNLIKELY(border_box_size.inline_size < |
| border_scrollbar_padding.InlineSum() && |
| scrollbar.InlineSum() && !constraint_space.IsAnonymous())) { |
| ClampScrollbarToContentBox( |
| &scrollbar, border_box_size.inline_size - border_padding.InlineSum()); |
| } |
| |
| return {border_box_size, border, scrollbar, padding}; |
| } |
| |
| NGFragmentGeometry CalculateInitialMinMaxFragmentGeometry( |
| const NGConstraintSpace& constraint_space, |
| const NGBlockNode& node) { |
| NGBoxStrut border = ComputeBorders(constraint_space, node); |
| NGBoxStrut padding = ComputePadding(constraint_space, node.Style()); |
| NGBoxStrut scrollbar = ComputeScrollbars(constraint_space, node); |
| |
| return {/* border_box_size */ LogicalSize(), border, scrollbar, padding}; |
| } |
| |
| LogicalSize ShrinkAvailableSize(LogicalSize size, const NGBoxStrut& inset) { |
| DCHECK_NE(size.inline_size, kIndefiniteSize); |
| size.inline_size -= inset.InlineSum(); |
| size.inline_size = std::max(size.inline_size, LayoutUnit()); |
| |
| if (size.block_size != kIndefiniteSize) { |
| size.block_size -= inset.BlockSum(); |
| size.block_size = std::max(size.block_size, LayoutUnit()); |
| } |
| |
| return size; |
| } |
| |
| namespace { |
| |
| // Implements the common part of the child percentage size calculation. Deals |
| // with how percentages are propagated from parent to child in quirks mode. |
| LogicalSize AdjustChildPercentageSizeForQuirksAndFlex( |
| const NGConstraintSpace& space, |
| const NGBlockNode node, |
| LogicalSize child_percentage_size, |
| LayoutUnit parent_percentage_block_size) { |
| // Flex items may have a fixed block-size, but children shouldn't resolve |
| // their percentages against this. |
| if (space.IsFixedBlockSize() && space.IsFixedBlockSizeIndefinite()) { |
| DCHECK(node.IsFlexItem()); |
| child_percentage_size.block_size = kIndefiniteSize; |
| return child_percentage_size; |
| } |
| |
| // In quirks mode the percentage resolution height is passed from parent to |
| // child. |
| // https://quirks.spec.whatwg.org/#the-percentage-height-calculation-quirk |
| if (child_percentage_size.block_size == kIndefiniteSize && |
| node.UseParentPercentageResolutionBlockSizeForChildren()) |
| child_percentage_size.block_size = parent_percentage_block_size; |
| |
| return child_percentage_size; |
| } |
| |
| } // namespace |
| |
| LogicalSize CalculateChildPercentageSize( |
| const NGConstraintSpace& space, |
| const NGBlockNode node, |
| const LogicalSize& child_available_size) { |
| // Anonymous block or spaces should pass the percent size straight through. |
| if (space.IsAnonymous() || node.IsAnonymousBlock()) |
| return space.PercentageResolutionSize(); |
| |
| LogicalSize child_percentage_size = child_available_size; |
| |
| bool is_table_cell_in_measure_phase = |
| space.IsTableCell() && !space.IsFixedBlockSize(); |
| |
| // Table cells which are measuring their content, force their children to |
| // have an indefinite percentage resolution size. |
| if (is_table_cell_in_measure_phase) { |
| child_percentage_size.block_size = kIndefiniteSize; |
| return child_percentage_size; |
| } |
| |
| // Table cell children don't apply the "percentage-quirk". I.e. if their |
| // percentage resolution block-size is indefinite, they don't pass through |
| // their parent's percentage resolution block-size. |
| if (space.TableCellChildLayoutMode() != |
| NGTableCellChildLayoutMode::kNotTableCellChild) |
| return child_percentage_size; |
| |
| return AdjustChildPercentageSizeForQuirksAndFlex( |
| space, node, child_percentage_size, |
| space.PercentageResolutionBlockSize()); |
| } |
| |
| LogicalSize CalculateReplacedChildPercentageSize( |
| const NGConstraintSpace& space, |
| const NGBlockNode node, |
| LogicalSize border_box_size, |
| const NGBoxStrut& border_scrollbar_padding, |
| const NGBoxStrut& border_padding) { |
| // Anonymous block or spaces should pass the percent size straight through. |
| if (space.IsAnonymous() || node.IsAnonymousBlock()) |
| return space.ReplacedPercentageResolutionSize(); |
| |
| bool has_resolvable_block_size = !node.Style().LogicalHeight().IsAuto() || |
| !node.Style().LogicalMinHeight().IsAuto(); |
| |
| bool is_table_cell_in_layout_phase = |
| space.IsTableCell() && space.IsFixedBlockSize(); |
| |
| // Table cells in the "layout" phase have a fixed block-size. However |
| // replaced children should resolve their percentages against the size given |
| // in the "measure" phase. |
| // |
| // To handle this we recalculate the border-box block-size, ignoring the |
| // fixed size constraint. |
| if (is_table_cell_in_layout_phase && has_resolvable_block_size) { |
| border_box_size.block_size = |
| ComputeBlockSizeForFragmentInternal(space, node.Style(), border_padding, |
| /* content_size */ kIndefiniteSize); |
| } |
| |
| LogicalSize child_percentage_size = |
| ShrinkAvailableSize(border_box_size, border_scrollbar_padding); |
| |
| return AdjustChildPercentageSizeForQuirksAndFlex( |
| space, node, child_percentage_size, |
| space.ReplacedPercentageResolutionBlockSize()); |
| } |
| |
| LayoutUnit CalculateChildPercentageBlockSizeForMinMax( |
| const NGConstraintSpace& space, |
| const NGBlockNode node, |
| const NGBoxStrut& border_padding, |
| LayoutUnit parent_percentage_block_size) { |
| // Anonymous block or spaces should pass the percent size straight through. |
| if (space.IsAnonymous() || node.IsAnonymousBlock()) |
| return parent_percentage_block_size; |
| |
| LayoutUnit block_size = ComputeBlockSizeForFragmentInternal( |
| space, node.Style(), border_padding, |
| CalculateDefaultBlockSize(space, node, border_padding), |
| &parent_percentage_block_size); |
| |
| LayoutUnit child_percentage_block_size = |
| block_size == kIndefiniteSize |
| ? kIndefiniteSize |
| : (block_size - border_padding.BlockSum()).ClampNegativeToZero(); |
| |
| // For OOF-positioned nodes, use the parent (containing-block) size. |
| if (child_percentage_block_size == kIndefiniteSize && |
| (node.UseParentPercentageResolutionBlockSizeForChildren() || |
| node.IsOutOfFlowPositioned())) |
| child_percentage_block_size = parent_percentage_block_size; |
| |
| return child_percentage_block_size; |
| } |
| |
| LayoutUnit ClampIntrinsicBlockSize(const NGBlockNode& node, |
| const NGBoxStrut& border_scrollbar_padding, |
| LayoutUnit current_intrinsic_block_size) { |
| // With contain: size, we ignore intrinsic sizing. If the block-size was |
| // specified as auto, its content-box size will become 0. |
| if (node.ShouldApplySizeContainment()) |
| return border_scrollbar_padding.BlockSum(); |
| |
| // If display locking induces size containment, then we replace its content |
| // size with the locked content size. |
| if (node.DisplayLockInducesSizeContainment()) { |
| return node.GetDisplayLockContext().GetLockedContentLogicalHeight() + |
| border_scrollbar_padding.BlockSum(); |
| } |
| |
| return current_intrinsic_block_size; |
| } |
| |
| base::Optional<MinMaxSize> CalculateMinMaxSizesIgnoringChildren( |
| const NGBlockNode& node, |
| const NGBoxStrut& border_scrollbar_padding, |
| NGMinMaxSizeType type) { |
| MinMaxSize sizes; |
| if (type == NGMinMaxSizeType::kBorderBoxSize) |
| sizes += border_scrollbar_padding.InlineSum(); |
| |
| // Size contained elements don't consider children for intrinsic sizing. |
| if (node.ShouldApplySizeContainment()) |
| return sizes; |
| |
| // Display locked elements override the content size, without considering |
| // children. Note that contain: size (above) takes precedence over display |
| // locking. |
| if (node.DisplayLockInducesSizeContainment()) { |
| sizes += node.GetDisplayLockContext().GetLockedContentLogicalWidth(); |
| return sizes; |
| } |
| |
| // If we don't have children, we can also determine the size immediately. |
| if (!node.FirstChild()) |
| return sizes; |
| |
| return base::nullopt; |
| } |
| |
| } // namespace blink |
