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659 lines
30 KiB
Rust
659 lines
30 KiB
Rust
/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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//! CSS tables.
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//!
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//! This follows the "More Precise Definitions of Inline Layout and Table Layout" proposal written
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//! by L. David Baron (Mozilla) here:
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//!
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//! http://dbaron.org/css/intrinsic/
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//!
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//! Hereafter this document is referred to as INTRINSIC.
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#![deny(unsafe_code)]
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use block::{BlockFlow, BlockNonReplaced, FloatNonReplaced, ISizeAndMarginsComputer};
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use block::{MarginsMayCollapseFlag};
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use context::LayoutContext;
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use floats::FloatKind;
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use flow::{FlowClass, Flow, ImmutableFlowUtils};
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use flow::{IMPACTED_BY_LEFT_FLOATS, IMPACTED_BY_RIGHT_FLOATS};
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use fragment::{Fragment, FragmentBorderBoxIterator};
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use table::{ChildInlineSizeInfo, ColumnComputedInlineSize, ColumnIntrinsicInlineSize};
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use wrapper::ThreadSafeLayoutNode;
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use geom::{Point2D, Rect};
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use util::geometry::Au;
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use std::cmp::{max, min};
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use std::fmt;
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use std::ops::Add;
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use std::sync::Arc;
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use style::computed_values::table_layout;
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use style::properties::ComputedValues;
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use style::values::CSSFloat;
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use style::values::computed::LengthOrPercentageOrAuto;
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#[derive(Copy, RustcEncodable, Debug)]
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pub enum TableLayout {
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Fixed,
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Auto
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}
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/// A table wrapper flow based on a block formatting context.
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#[derive(RustcEncodable)]
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pub struct TableWrapperFlow {
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pub block_flow: BlockFlow,
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/// Intrinsic column inline sizes according to INTRINSIC § 4.1
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pub column_intrinsic_inline_sizes: Vec<ColumnIntrinsicInlineSize>,
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/// Table-layout property
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pub table_layout: TableLayout,
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}
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impl TableWrapperFlow {
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pub fn from_node_and_fragment(node: &ThreadSafeLayoutNode,
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fragment: Fragment)
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-> TableWrapperFlow {
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let mut block_flow = BlockFlow::from_node_and_fragment(node, fragment);
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let table_layout = if block_flow.fragment().style().get_table().table_layout ==
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table_layout::T::fixed {
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TableLayout::Fixed
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} else {
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TableLayout::Auto
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};
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TableWrapperFlow {
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block_flow: block_flow,
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column_intrinsic_inline_sizes: vec!(),
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table_layout: table_layout
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}
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}
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pub fn float_from_node_and_fragment(node: &ThreadSafeLayoutNode,
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fragment: Fragment,
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float_kind: FloatKind)
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-> TableWrapperFlow {
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let mut block_flow = BlockFlow::float_from_node_and_fragment(node, fragment, float_kind);
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let table_layout = if block_flow.fragment().style().get_table().table_layout ==
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table_layout::T::fixed {
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TableLayout::Fixed
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} else {
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TableLayout::Auto
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};
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TableWrapperFlow {
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block_flow: block_flow,
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column_intrinsic_inline_sizes: vec!(),
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table_layout: table_layout
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}
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}
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/// Calculates table column sizes for automatic layout per INTRINSIC § 4.3.
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fn calculate_table_column_sizes_for_automatic_layout(
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&mut self,
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intermediate_column_inline_sizes: &mut [IntermediateColumnInlineSize]) {
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// Find the padding and border of our first child, which is the table itself.
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//
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// This is a little weird because we're computing border/padding/margins for our child,
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// when normally the child computes it itself. But it has to be this way because the
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// padding will affect where we place the child. This is an odd artifact of the way that
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// tables are separated into table flows and table wrapper flows.
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let mut available_inline_size = self.block_flow.fragment.border_box.size.inline;
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let (mut table_border_padding, mut spacing) = (Au(0), Au(0));
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for kid in self.block_flow.base.child_iter() {
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if kid.is_table() {
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let kid_block = kid.as_block();
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let spacing_per_cell = kid_block.fragment
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.style()
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.get_inheritedtable()
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.border_spacing
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.horizontal;
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spacing = spacing_per_cell * (self.column_intrinsic_inline_sizes.len() as i32 + 1);
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available_inline_size = self.block_flow.fragment.border_box.size.inline;
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kid_block.fragment.compute_border_and_padding(available_inline_size);
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kid_block.fragment.compute_block_direction_margins(available_inline_size);
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kid_block.fragment.compute_inline_direction_margins(available_inline_size);
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table_border_padding = kid_block.fragment.border_padding.inline_start_end();
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break
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}
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}
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// FIXME(pcwalton, spec): INTRINSIC § 8 does not properly define how to compute this, but
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// says "the basic idea is the same as the shrink-to-fit width that CSS2.1 defines". So we
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// just use the shrink-to-fit inline size.
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let mut available_inline_size =
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match self.block_flow.fragment.style().content_inline_size() {
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LengthOrPercentageOrAuto::Auto => {
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self.block_flow.get_shrink_to_fit_inline_size(available_inline_size)
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}
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// FIXME(mttr): This fixes #4421 without breaking our current reftests, but I'm
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// not completely sure this is "correct".
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//
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// That said, `available_inline_size` is, as far as I can tell, equal to the
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// table's computed width property (W) and is used from this point forward in a way
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// that seems to correspond with CSS 2.1 § 17.5.2.2 under "Column and caption
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// widths influence the final table width as follows: …"
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_ => available_inline_size,
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};
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available_inline_size = available_inline_size - spacing;
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// Compute all the guesses for the column sizes, and sum them.
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let mut total_guess = AutoLayoutCandidateGuess::new();
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let guesses: Vec<AutoLayoutCandidateGuess> =
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self.column_intrinsic_inline_sizes.iter().map(|column_intrinsic_inline_size| {
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let guess = AutoLayoutCandidateGuess::from_column_intrinsic_inline_size(
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column_intrinsic_inline_size,
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available_inline_size);
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total_guess = &total_guess + &guess;
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guess
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}).collect();
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// Assign inline sizes.
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let selection = SelectedAutoLayoutCandidateGuess::select(&total_guess,
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available_inline_size);
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let mut total_used_inline_size = Au(0);
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for (intermediate_column_inline_size, guess) in
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intermediate_column_inline_sizes.iter_mut().zip(guesses.iter()) {
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intermediate_column_inline_size.size = guess.calculate(selection);
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intermediate_column_inline_size.percentage = 0.0;
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total_used_inline_size = total_used_inline_size + intermediate_column_inline_size.size
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}
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// Distribute excess inline-size if necessary per INTRINSIC § 4.4.
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//
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// FIXME(pcwalton, spec): How do I deal with fractional excess?
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let excess_inline_size = available_inline_size - total_used_inline_size;
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if excess_inline_size > Au(0) && selection ==
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SelectedAutoLayoutCandidateGuess::UsePreferredGuessAndDistributeExcessInlineSize {
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let mut info = ExcessInlineSizeDistributionInfo::new();
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for column_intrinsic_inline_size in self.column_intrinsic_inline_sizes.iter() {
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info.update(column_intrinsic_inline_size)
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}
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let mut total_distributed_excess_size = Au(0);
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for (intermediate_column_inline_size, column_intrinsic_inline_size) in
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intermediate_column_inline_sizes.iter_mut()
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.zip(self.column_intrinsic_inline_sizes
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.iter()) {
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info.distribute_excess_inline_size_to_column(intermediate_column_inline_size,
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column_intrinsic_inline_size,
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excess_inline_size,
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&mut total_distributed_excess_size)
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}
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total_used_inline_size = available_inline_size
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}
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self.block_flow.fragment.border_box.size.inline = total_used_inline_size +
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table_border_padding + spacing;
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self.block_flow.base.position.size.inline = total_used_inline_size +
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table_border_padding + spacing + self.block_flow.fragment.margin.inline_start_end();
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}
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fn compute_used_inline_size(&mut self,
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layout_context: &LayoutContext,
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parent_flow_inline_size: Au) {
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// Delegate to the appropriate inline size computer to find the constraint inputs.
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let input = if self.block_flow.base.flags.is_float() {
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FloatNonReplaced.compute_inline_size_constraint_inputs(&mut self.block_flow,
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parent_flow_inline_size,
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layout_context)
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} else {
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BlockNonReplaced.compute_inline_size_constraint_inputs(&mut self.block_flow,
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parent_flow_inline_size,
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layout_context)
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};
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// Delegate to the appropriate inline size computer to write the constraint solutions in.
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if self.block_flow.base.flags.is_float() {
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let solution = FloatNonReplaced.solve_inline_size_constraints(&mut self.block_flow,
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&input);
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FloatNonReplaced.set_inline_size_constraint_solutions(&mut self.block_flow, solution);
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FloatNonReplaced.set_flow_x_coord_if_necessary(&mut self.block_flow, solution);
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} else {
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let solution = BlockNonReplaced.solve_inline_size_constraints(&mut self.block_flow,
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&input);
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BlockNonReplaced.set_inline_size_constraint_solutions(&mut self.block_flow, solution);
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BlockNonReplaced.set_flow_x_coord_if_necessary(&mut self.block_flow, solution);
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}
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}
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}
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impl Flow for TableWrapperFlow {
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fn class(&self) -> FlowClass {
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FlowClass::TableWrapper
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}
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fn as_table_wrapper<'a>(&'a mut self) -> &'a mut TableWrapperFlow {
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self
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}
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fn as_immutable_table_wrapper<'a>(&'a self) -> &'a TableWrapperFlow {
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self
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}
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fn as_block<'a>(&'a mut self) -> &'a mut BlockFlow {
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&mut self.block_flow
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}
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fn bubble_inline_sizes(&mut self) {
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// Get the intrinsic column inline-sizes info from the table flow.
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for kid in self.block_flow.base.child_iter() {
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debug_assert!(kid.is_table_caption() || kid.is_table());
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if kid.is_table() {
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self.column_intrinsic_inline_sizes = kid.column_intrinsic_inline_sizes().clone()
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}
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}
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self.block_flow.bubble_inline_sizes();
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}
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fn assign_inline_sizes(&mut self, layout_context: &LayoutContext) {
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debug!("assign_inline_sizes({}): assigning inline_size for flow",
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if self.block_flow.base.flags.is_float() {
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"floated table_wrapper"
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} else {
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"table_wrapper"
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});
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let mut intermediate_column_inline_sizes = self.column_intrinsic_inline_sizes
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.iter()
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.map(|column_intrinsic_inline_size| {
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IntermediateColumnInlineSize {
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size: column_intrinsic_inline_size.minimum_length,
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percentage: column_intrinsic_inline_size.percentage,
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}
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}).collect::<Vec<_>>();
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// Table wrappers are essentially block formatting contexts and are therefore never
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// impacted by floats.
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self.block_flow.base.flags.remove(IMPACTED_BY_LEFT_FLOATS);
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self.block_flow.base.flags.remove(IMPACTED_BY_RIGHT_FLOATS);
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// Our inline-size was set to the inline-size of the containing block by the flow's parent.
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// Now compute the real value.
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let containing_block_inline_size = self.block_flow.base.block_container_inline_size;
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if self.block_flow.base.flags.is_float() {
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self.block_flow.float.as_mut().unwrap().containing_inline_size =
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containing_block_inline_size;
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}
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self.compute_used_inline_size(layout_context, containing_block_inline_size);
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match self.table_layout {
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TableLayout::Fixed => {}
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TableLayout::Auto => {
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self.calculate_table_column_sizes_for_automatic_layout(
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intermediate_column_inline_sizes.as_mut_slice())
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}
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}
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let inline_start_content_edge = self.block_flow.fragment.border_box.start.i;
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let content_inline_size = self.block_flow.fragment.border_box.size.inline;
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// FIXME (mbrubeck): Test mixed RTL/LTR table layout, make sure this is right.
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let inline_end_content_edge = self.block_flow.base.block_container_inline_size -
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self.block_flow.fragment.margin.inline_end -
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content_inline_size -
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inline_start_content_edge;
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// In case of fixed layout, column inline-sizes are calculated in table flow.
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let assigned_column_inline_sizes = match self.table_layout {
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TableLayout::Fixed => None,
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TableLayout::Auto => {
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Some(intermediate_column_inline_sizes.iter().map(|sizes| {
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ColumnComputedInlineSize {
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size: sizes.size,
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}
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}).collect::<Vec<_>>())
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}
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};
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match assigned_column_inline_sizes {
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None => {
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self.block_flow.propagate_assigned_inline_size_to_children(
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layout_context,
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inline_start_content_edge,
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inline_end_content_edge,
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content_inline_size,
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None)
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}
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Some(ref assigned_column_inline_sizes) => {
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let info = ChildInlineSizeInfo {
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column_computed_inline_sizes: assigned_column_inline_sizes.as_slice(),
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spacing: self.block_flow.fragment.style().get_inheritedtable().border_spacing,
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};
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self.block_flow
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.propagate_assigned_inline_size_to_children(layout_context,
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inline_start_content_edge,
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inline_end_content_edge,
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content_inline_size,
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Some(info));
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}
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}
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}
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fn assign_block_size<'a>(&mut self, ctx: &'a LayoutContext<'a>) {
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debug!("assign_block_size: assigning block_size for table_wrapper");
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self.block_flow.assign_block_size_block_base(ctx, MarginsMayCollapseFlag::MarginsMayNotCollapse);
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}
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fn compute_absolute_position(&mut self) {
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self.block_flow.compute_absolute_position()
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}
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fn place_float_if_applicable<'a>(&mut self, layout_context: &'a LayoutContext<'a>) {
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self.block_flow.place_float_if_applicable(layout_context)
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}
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fn assign_block_size_for_inorder_child_if_necessary<'a>(&mut self,
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layout_context: &'a LayoutContext<'a>,
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parent_thread_id: u8)
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-> bool {
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if self.block_flow.base.flags.is_float() {
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self.block_flow.place_float();
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return true
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}
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let impacted = self.block_flow.base.flags.impacted_by_floats();
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if impacted {
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self.block_flow.base.thread_id = parent_thread_id;
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self.assign_block_size(layout_context);
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}
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impacted
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}
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fn update_late_computed_inline_position_if_necessary(&mut self, inline_position: Au) {
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self.block_flow.update_late_computed_inline_position_if_necessary(inline_position)
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}
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fn update_late_computed_block_position_if_necessary(&mut self, block_position: Au) {
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self.block_flow.update_late_computed_block_position_if_necessary(block_position)
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}
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fn build_display_list(&mut self, layout_context: &LayoutContext) {
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self.block_flow.build_display_list(layout_context)
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}
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fn repair_style(&mut self, new_style: &Arc<ComputedValues>) {
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self.block_flow.repair_style(new_style)
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}
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fn compute_overflow(&self) -> Rect<Au> {
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self.block_flow.compute_overflow()
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}
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fn iterate_through_fragment_border_boxes(&self,
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iterator: &mut FragmentBorderBoxIterator,
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stacking_context_position: &Point2D<Au>) {
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self.block_flow.iterate_through_fragment_border_boxes(iterator, stacking_context_position)
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}
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fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
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self.block_flow.mutate_fragments(mutator)
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}
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}
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impl fmt::Debug for TableWrapperFlow {
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fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
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if self.block_flow.base.flags.is_float() {
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write!(f, "TableWrapperFlow(Float): {:?}", self.block_flow.fragment)
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} else {
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write!(f, "TableWrapperFlow: {:?}", self.block_flow.fragment)
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}
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}
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}
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/// The layout "guesses" defined in INTRINSIC § 4.3.
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struct AutoLayoutCandidateGuess {
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/// The column inline-size assignment where each column is assigned its intrinsic minimum
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/// inline-size.
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minimum_guess: Au,
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/// The column inline-size assignment where:
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/// * A column with an intrinsic percentage inline-size greater than 0% is assigned the
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/// larger of:
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/// - Its intrinsic percentage inline-size times the assignable inline-size;
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/// - Its intrinsic minimum inline-size;
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/// * Other columns receive their intrinsic minimum inline-size.
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minimum_percentage_guess: Au,
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/// The column inline-size assignment where:
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/// * Each column with an intrinsic percentage inline-size greater than 0% is assigned the
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/// larger of:
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/// - Its intrinsic percentage inline-size times the assignable inline-size;
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/// - Its intrinsic minimum inline-size;
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/// * Any other column that is constrained is assigned its intrinsic preferred inline-size;
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/// * Other columns are assigned their intrinsic minimum inline-size.
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minimum_specified_guess: Au,
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/// The column inline-size assignment where:
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/// * Each column with an intrinsic percentage inline-size greater than 0% is assigned the
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/// larger of:
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/// - Its intrinsic percentage inline-size times the assignable inline-size;
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/// - Its intrinsic minimum inline-size;
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/// * Other columns are assigned their intrinsic preferred inline-size.
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preferred_guess: Au,
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}
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impl AutoLayoutCandidateGuess {
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/// Creates a guess with all elements initialized to zero.
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fn new() -> AutoLayoutCandidateGuess {
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AutoLayoutCandidateGuess {
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minimum_guess: Au(0),
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minimum_percentage_guess: Au(0),
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minimum_specified_guess: Au(0),
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preferred_guess: Au(0),
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}
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}
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/// Fills in the inline-size guesses for this column per INTRINSIC § 4.3.
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fn from_column_intrinsic_inline_size(column_intrinsic_inline_size: &ColumnIntrinsicInlineSize,
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assignable_inline_size: Au)
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-> AutoLayoutCandidateGuess {
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let minimum_percentage_guess =
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max(assignable_inline_size.scale_by(column_intrinsic_inline_size.percentage),
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column_intrinsic_inline_size.minimum_length);
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AutoLayoutCandidateGuess {
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|
minimum_guess: column_intrinsic_inline_size.minimum_length,
|
|
minimum_percentage_guess: minimum_percentage_guess,
|
|
// FIXME(pcwalton): We need the notion of *constrainedness* per INTRINSIC § 4 to
|
|
// implement this one correctly.
|
|
minimum_specified_guess: if column_intrinsic_inline_size.percentage > 0.0 {
|
|
minimum_percentage_guess
|
|
} else if column_intrinsic_inline_size.constrained {
|
|
column_intrinsic_inline_size.preferred
|
|
} else {
|
|
column_intrinsic_inline_size.minimum_length
|
|
},
|
|
preferred_guess: if column_intrinsic_inline_size.percentage > 0.0 {
|
|
minimum_percentage_guess
|
|
} else {
|
|
column_intrinsic_inline_size.preferred
|
|
},
|
|
}
|
|
}
|
|
|
|
/// Calculates the inline-size, interpolating appropriately based on the value of `selection`.
|
|
///
|
|
/// This does *not* distribute excess inline-size. That must be done later if necessary.
|
|
fn calculate(&self, selection: SelectedAutoLayoutCandidateGuess) -> Au {
|
|
match selection {
|
|
SelectedAutoLayoutCandidateGuess::UseMinimumGuess => self.minimum_guess,
|
|
SelectedAutoLayoutCandidateGuess::
|
|
InterpolateBetweenMinimumGuessAndMinimumPercentageGuess(weight) => {
|
|
interp(self.minimum_guess, self.minimum_percentage_guess, weight)
|
|
}
|
|
SelectedAutoLayoutCandidateGuess::
|
|
InterpolateBetweenMinimumPercentageGuessAndMinimumSpecifiedGuess(weight) => {
|
|
interp(self.minimum_percentage_guess, self.minimum_specified_guess, weight)
|
|
}
|
|
SelectedAutoLayoutCandidateGuess::
|
|
InterpolateBetweenMinimumSpecifiedGuessAndPreferredGuess(weight) => {
|
|
interp(self.minimum_specified_guess, self.preferred_guess, weight)
|
|
}
|
|
SelectedAutoLayoutCandidateGuess::UsePreferredGuessAndDistributeExcessInlineSize => {
|
|
self.preferred_guess
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
impl<'a> Add for &'a AutoLayoutCandidateGuess {
|
|
type Output = AutoLayoutCandidateGuess;
|
|
#[inline]
|
|
fn add(self, other: &AutoLayoutCandidateGuess) -> AutoLayoutCandidateGuess {
|
|
AutoLayoutCandidateGuess {
|
|
minimum_guess: self.minimum_guess + other.minimum_guess,
|
|
minimum_percentage_guess:
|
|
self.minimum_percentage_guess + other.minimum_percentage_guess,
|
|
minimum_specified_guess: self.minimum_specified_guess + other.minimum_specified_guess,
|
|
preferred_guess: self.preferred_guess + other.preferred_guess,
|
|
}
|
|
}
|
|
}
|
|
|
|
/// The `CSSFloat` member specifies the weight of the smaller of the two guesses, on a scale from
|
|
/// 0.0 to 1.0.
|
|
#[derive(Copy, PartialEq, Debug)]
|
|
enum SelectedAutoLayoutCandidateGuess {
|
|
UseMinimumGuess,
|
|
InterpolateBetweenMinimumGuessAndMinimumPercentageGuess(CSSFloat),
|
|
InterpolateBetweenMinimumPercentageGuessAndMinimumSpecifiedGuess(CSSFloat),
|
|
InterpolateBetweenMinimumSpecifiedGuessAndPreferredGuess(CSSFloat),
|
|
UsePreferredGuessAndDistributeExcessInlineSize,
|
|
}
|
|
|
|
impl SelectedAutoLayoutCandidateGuess {
|
|
/// See INTRINSIC § 4.3.
|
|
///
|
|
/// FIXME(pcwalton, INTRINSIC spec): INTRINSIC doesn't specify whether these are exclusive or
|
|
/// inclusive ranges.
|
|
fn select(guess: &AutoLayoutCandidateGuess, assignable_inline_size: Au)
|
|
-> SelectedAutoLayoutCandidateGuess {
|
|
if assignable_inline_size < guess.minimum_guess {
|
|
SelectedAutoLayoutCandidateGuess::UseMinimumGuess
|
|
} else if assignable_inline_size < guess.minimum_percentage_guess {
|
|
let weight = weight(guess.minimum_guess,
|
|
assignable_inline_size,
|
|
guess.minimum_percentage_guess);
|
|
SelectedAutoLayoutCandidateGuess::InterpolateBetweenMinimumGuessAndMinimumPercentageGuess(weight)
|
|
} else if assignable_inline_size < guess.minimum_specified_guess {
|
|
let weight = weight(guess.minimum_percentage_guess,
|
|
assignable_inline_size,
|
|
guess.minimum_specified_guess);
|
|
SelectedAutoLayoutCandidateGuess::InterpolateBetweenMinimumPercentageGuessAndMinimumSpecifiedGuess(weight)
|
|
} else if assignable_inline_size < guess.preferred_guess {
|
|
let weight = weight(guess.minimum_specified_guess,
|
|
assignable_inline_size,
|
|
guess.preferred_guess);
|
|
SelectedAutoLayoutCandidateGuess::InterpolateBetweenMinimumSpecifiedGuessAndPreferredGuess(weight)
|
|
} else {
|
|
SelectedAutoLayoutCandidateGuess::UsePreferredGuessAndDistributeExcessInlineSize
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Computes the weight needed to linearly interpolate `middle` between two guesses `low` and
|
|
/// `high` as specified by INTRINSIC § 4.3.
|
|
fn weight(low: Au, middle: Au, high: Au) -> CSSFloat {
|
|
(middle - low).to_subpx() / (high - low).to_subpx()
|
|
}
|
|
|
|
/// Linearly interpolates between two guesses, as specified by INTRINSIC § 4.3.
|
|
fn interp(low: Au, high: Au, weight: CSSFloat) -> Au {
|
|
low + (high - low).scale_by(weight)
|
|
}
|
|
|
|
struct ExcessInlineSizeDistributionInfo {
|
|
preferred_inline_size_of_nonconstrained_columns_with_no_percentage: Au,
|
|
count_of_nonconstrained_columns_with_no_percentage: u32,
|
|
preferred_inline_size_of_constrained_columns_with_no_percentage: Au,
|
|
total_percentage: CSSFloat,
|
|
column_count: u32,
|
|
}
|
|
|
|
impl ExcessInlineSizeDistributionInfo {
|
|
fn new() -> ExcessInlineSizeDistributionInfo {
|
|
ExcessInlineSizeDistributionInfo {
|
|
preferred_inline_size_of_nonconstrained_columns_with_no_percentage: Au(0),
|
|
count_of_nonconstrained_columns_with_no_percentage: 0,
|
|
preferred_inline_size_of_constrained_columns_with_no_percentage: Au(0),
|
|
total_percentage: 0.0,
|
|
column_count: 0,
|
|
}
|
|
}
|
|
|
|
fn update(&mut self, column_intrinsic_inline_size: &ColumnIntrinsicInlineSize) {
|
|
if !column_intrinsic_inline_size.constrained &&
|
|
column_intrinsic_inline_size.percentage == 0.0 {
|
|
self.preferred_inline_size_of_nonconstrained_columns_with_no_percentage =
|
|
self.preferred_inline_size_of_nonconstrained_columns_with_no_percentage +
|
|
column_intrinsic_inline_size.preferred;
|
|
self.count_of_nonconstrained_columns_with_no_percentage += 1
|
|
}
|
|
if column_intrinsic_inline_size.constrained &&
|
|
column_intrinsic_inline_size.percentage == 0.0 {
|
|
self.preferred_inline_size_of_constrained_columns_with_no_percentage =
|
|
self.preferred_inline_size_of_constrained_columns_with_no_percentage +
|
|
column_intrinsic_inline_size.preferred
|
|
}
|
|
self.total_percentage += column_intrinsic_inline_size.percentage;
|
|
self.column_count += 1
|
|
}
|
|
|
|
/// Based on the information here, distributes excess inline-size to the given column per
|
|
/// INTRINSIC § 4.4.
|
|
///
|
|
/// `#[inline]` so the compiler will hoist out the branch, which is loop-invariant.
|
|
#[inline]
|
|
fn distribute_excess_inline_size_to_column(
|
|
&self,
|
|
intermediate_column_inline_size: &mut IntermediateColumnInlineSize,
|
|
column_intrinsic_inline_size: &ColumnIntrinsicInlineSize,
|
|
excess_inline_size: Au,
|
|
total_distributed_excess_size: &mut Au) {
|
|
let proportion =
|
|
if self.preferred_inline_size_of_nonconstrained_columns_with_no_percentage > Au(0) {
|
|
// FIXME(spec, pcwalton): Gecko and WebKit do *something* here when there are
|
|
// nonconstrained columns with no percentage *and* no preferred width. What do they
|
|
// do?
|
|
if !column_intrinsic_inline_size.constrained &&
|
|
column_intrinsic_inline_size.percentage == 0.0 {
|
|
column_intrinsic_inline_size.preferred.to_subpx() /
|
|
self.preferred_inline_size_of_nonconstrained_columns_with_no_percentage
|
|
.to_subpx()
|
|
} else {
|
|
0.0
|
|
}
|
|
} else if self.count_of_nonconstrained_columns_with_no_percentage > 0 {
|
|
1.0 / (self.count_of_nonconstrained_columns_with_no_percentage as CSSFloat)
|
|
} else if self.preferred_inline_size_of_constrained_columns_with_no_percentage >
|
|
Au(0) {
|
|
column_intrinsic_inline_size.preferred.to_subpx() /
|
|
self.preferred_inline_size_of_constrained_columns_with_no_percentage.to_subpx()
|
|
} else if self.total_percentage > 0.0 {
|
|
column_intrinsic_inline_size.percentage / self.total_percentage
|
|
} else {
|
|
1.0 / (self.column_count as CSSFloat)
|
|
};
|
|
|
|
// The `min` here has the effect of throwing away fractional excess at the end of the
|
|
// table.
|
|
let amount_to_distribute = min(excess_inline_size.scale_by(proportion),
|
|
excess_inline_size - *total_distributed_excess_size);
|
|
*total_distributed_excess_size = *total_distributed_excess_size + amount_to_distribute;
|
|
intermediate_column_inline_size.size = intermediate_column_inline_size.size +
|
|
amount_to_distribute
|
|
}
|
|
}
|
|
|
|
/// An intermediate column size assignment.
|
|
struct IntermediateColumnInlineSize {
|
|
size: Au,
|
|
percentage: f64,
|
|
}
|
|
|