mirror of
https://github.com/servo/servo.git
synced 2025-08-07 06:25:32 +01:00
Simon Sapin
Anthony Ramine
parent
be0e84b30f
commit
86904757e6
12 changed files with 2728 additions and 0 deletions
625
components/layout_2020/flow/construct.rs
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625
components/layout_2020/flow/construct.rs
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@ -0,0 +1,625 @@
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use super::*;
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impl BlockFormattingContext {
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pub fn construct<'a>(
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context: &'a Context<'a>,
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style: &'a Arc<ComputedValues>,
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contents: NonReplacedContents,
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) -> Self {
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let (contents, contains_floats) = BlockContainer::construct(context, style, contents);
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Self {
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contents,
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contains_floats: contains_floats == ContainsFloats::Yes,
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}
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}
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}
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enum IntermediateBlockLevelBox {
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SameFormattingContextBlock {
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style: Arc<ComputedValues>,
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contents: IntermediateBlockContainer,
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},
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Independent {
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style: Arc<ComputedValues>,
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display_inside: DisplayInside,
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contents: Contents,
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},
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OutOfFlowAbsolutelyPositionedBox {
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style: Arc<ComputedValues>,
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display_inside: DisplayInside,
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contents: Contents,
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},
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OutOfFlowFloatBox {
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style: Arc<ComputedValues>,
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display_inside: DisplayInside,
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contents: Contents,
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},
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}
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/// A block container that may still have to be constructed.
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///
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/// Represents either the inline formatting context of an anonymous block
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/// box or the yet-to-be-computed block container generated from the children
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/// of a given element.
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///
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/// Deferring allows using rayon’s `into_par_iter`.
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enum IntermediateBlockContainer {
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InlineFormattingContext(InlineFormattingContext),
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Deferred { contents: NonReplacedContents },
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}
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/// A builder for a block container.
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///
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/// This builder starts from the first child of a given DOM node
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/// and does a preorder traversal of all of its inclusive siblings.
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struct BlockContainerBuilder<'a> {
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context: &'a Context<'a>,
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block_container_style: &'a Arc<ComputedValues>,
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/// The list of block-level boxes of the final block container.
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///
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/// Contains all the complete block level boxes we found traversing the tree
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/// so far, if this is empty at the end of the traversal and the ongoing
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/// inline formatting context is not empty, the block container establishes
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/// an inline formatting context (see end of `build`).
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///
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/// DOM nodes which represent block-level boxes are immediately pushed
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/// to this list with their style without ever being traversed at this
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/// point, instead we just move to their next sibling. If the DOM node
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/// doesn't have a next sibling, we either reached the end of the container
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/// root or there are ongoing inline-level boxes
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/// (see `handle_block_level_element`).
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block_level_boxes: Vec<(IntermediateBlockLevelBox, BoxSlot<'a>)>,
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/// The ongoing inline formatting context of the builder.
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///
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/// Contains all the complete inline level boxes we found traversing the
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/// tree so far. If a block-level box is found during traversal,
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/// this inline formatting context is pushed as a block level box to
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/// the list of block-level boxes of the builder
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/// (see `end_ongoing_inline_formatting_context`).
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ongoing_inline_formatting_context: InlineFormattingContext,
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/// The ongoing stack of inline boxes stack of the builder.
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///
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/// Contains all the currently ongoing inline boxes we entered so far.
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/// The traversal is at all times as deep in the tree as this stack is,
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/// which is why the code doesn't need to keep track of the actual
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/// container root (see `handle_inline_level_element`).
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///
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/// Whenever the end of a DOM element that represents an inline box is
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/// reached, the inline box at the top of this stack is complete and ready
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/// to be pushed to the children of the next last ongoing inline box
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/// the ongoing inline formatting context if the stack is now empty,
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/// which means we reached the end of a child of the actual
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/// container root (see `move_to_next_sibling`).
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ongoing_inline_boxes_stack: Vec<InlineBox>,
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/// The style of the anonymous block boxes pushed to the list of block-level
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/// boxes, if any (see `end_ongoing_inline_formatting_context`).
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anonymous_style: Option<Arc<ComputedValues>>,
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/// Whether the resulting block container contains any float box.
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contains_floats: ContainsFloats,
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}
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impl BlockContainer {
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pub fn construct<'a>(
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context: &'a Context<'a>,
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block_container_style: &'a Arc<ComputedValues>,
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contents: NonReplacedContents,
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) -> (BlockContainer, ContainsFloats) {
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let mut builder = BlockContainerBuilder {
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context,
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block_container_style,
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block_level_boxes: Default::default(),
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ongoing_inline_formatting_context: Default::default(),
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ongoing_inline_boxes_stack: Default::default(),
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anonymous_style: Default::default(),
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contains_floats: Default::default(),
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};
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contents.traverse(block_container_style, context, &mut builder);
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debug_assert!(builder.ongoing_inline_boxes_stack.is_empty());
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if !builder
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.ongoing_inline_formatting_context
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.inline_level_boxes
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.is_empty()
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{
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if builder.block_level_boxes.is_empty() {
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let container = BlockContainer::InlineFormattingContext(
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builder.ongoing_inline_formatting_context,
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);
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return (container, builder.contains_floats);
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}
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builder.end_ongoing_inline_formatting_context();
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}
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let mut contains_floats = builder.contains_floats;
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let container = BlockContainer::BlockLevelBoxes(
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builder
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.block_level_boxes
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.into_par_iter()
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.mapfold_reduce_into(
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&mut contains_floats,
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|contains_floats, (intermediate, box_slot)| {
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let (block_level_box, box_contains_floats) = intermediate.finish(context);
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*contains_floats |= box_contains_floats;
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box_slot.set(LayoutBox::BlockLevel(block_level_box.clone()));
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block_level_box
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},
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|left, right| *left |= right,
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)
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.collect(),
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);
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(container, contains_floats)
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}
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}
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impl<'a> TraversalHandler<'a> for BlockContainerBuilder<'a> {
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fn handle_element(
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&mut self,
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style: &Arc<ComputedValues>,
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display: DisplayGeneratingBox,
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contents: Contents,
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box_slot: BoxSlot<'a>,
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) {
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match display {
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DisplayGeneratingBox::OutsideInside { outside, inside } => match outside {
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DisplayOutside::Inline => box_slot.set(LayoutBox::InlineLevel(
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self.handle_inline_level_element(style, inside, contents),
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)),
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DisplayOutside::Block => {
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// Floats and abspos cause blockification, so they only happen in this case.
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// https://drafts.csswg.org/css2/visuren.html#dis-pos-flo
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if style.box_.position.is_absolutely_positioned() {
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self.handle_absolutely_positioned_element(
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style.clone(),
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inside,
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contents,
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box_slot,
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)
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} else if style.box_.float.is_floating() {
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self.handle_float_element(style.clone(), inside, contents, box_slot)
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} else {
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self.handle_block_level_element(style.clone(), inside, contents, box_slot)
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}
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}
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},
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}
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}
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fn handle_text(&mut self, input: &str, parent_style: &Arc<ComputedValues>) {
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let (leading_whitespace, mut input) = self.handle_leading_whitespace(input);
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if leading_whitespace || !input.is_empty() {
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// This text node should be pushed either to the next ongoing
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// inline level box with the parent style of that inline level box
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// that will be ended, or directly to the ongoing inline formatting
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// context with the parent style of that builder.
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let inlines = self.current_inline_level_boxes();
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fn last_text(inlines: &mut [Arc<InlineLevelBox>]) -> Option<&mut String> {
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let last = inlines.last_mut()?;
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if let InlineLevelBox::TextRun(_) = &**last {
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// We never clone text run boxes, so the refcount is 1 and unwrap succeeds:
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let last = Arc::get_mut(last).unwrap();
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if let InlineLevelBox::TextRun(TextRun { text, .. }) = last {
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Some(text)
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} else {
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unreachable!()
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}
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} else {
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None
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}
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}
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let mut new_text_run_contents;
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let output;
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if let Some(text) = last_text(inlines) {
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// Append to the existing text run
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new_text_run_contents = None;
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output = text;
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} else {
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new_text_run_contents = Some(String::new());
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output = new_text_run_contents.as_mut().unwrap();
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}
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if leading_whitespace {
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output.push(' ')
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}
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loop {
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if let Some(i) = input.bytes().position(|b| b.is_ascii_whitespace()) {
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let (non_whitespace, rest) = input.split_at(i);
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output.push_str(non_whitespace);
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output.push(' ');
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if let Some(i) = rest.bytes().position(|b| !b.is_ascii_whitespace()) {
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input = &rest[i..];
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} else {
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break;
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}
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} else {
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output.push_str(input);
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break;
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}
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}
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if let Some(text) = new_text_run_contents {
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let parent_style = parent_style.clone();
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inlines.push(Arc::new(InlineLevelBox::TextRun(TextRun {
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parent_style,
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text,
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})))
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}
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}
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}
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}
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impl<'a> BlockContainerBuilder<'a> {
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/// Returns:
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///
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/// * Whether this text run has preserved (non-collapsible) leading whitespace
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/// * The contents starting at the first non-whitespace character (or the empty string)
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fn handle_leading_whitespace<'text>(&mut self, text: &'text str) -> (bool, &'text str) {
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// FIXME: this is only an approximation of
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// https://drafts.csswg.org/css2/text.html#white-space-model
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if !text.starts_with(|c: char| c.is_ascii_whitespace()) {
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return (false, text);
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}
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let mut inline_level_boxes = self.current_inline_level_boxes().iter().rev();
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let mut stack = Vec::new();
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let preserved = loop {
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match inline_level_boxes.next().map(|b| &**b) {
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Some(InlineLevelBox::TextRun(r)) => break !r.text.ends_with(' '),
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Some(InlineLevelBox::Atomic { .. }) => break false,
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Some(InlineLevelBox::OutOfFlowAbsolutelyPositionedBox(_))
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| Some(InlineLevelBox::OutOfFlowFloatBox(_)) => {}
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Some(InlineLevelBox::InlineBox(b)) => {
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stack.push(inline_level_boxes);
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inline_level_boxes = b.children.iter().rev()
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}
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None => {
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if let Some(iter) = stack.pop() {
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inline_level_boxes = iter
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} else {
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break false; // Paragraph start
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}
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}
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}
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};
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let text = text.trim_start_matches(|c: char| c.is_ascii_whitespace());
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(preserved, text)
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}
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fn handle_inline_level_element(
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&mut self,
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style: &Arc<ComputedValues>,
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display_inside: DisplayInside,
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contents: Contents,
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) -> Arc<InlineLevelBox> {
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let box_ = match contents.try_into() {
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Err(replaced) => Arc::new(InlineLevelBox::Atomic {
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style: style.clone(),
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contents: replaced,
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}),
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Ok(non_replaced) => match display_inside {
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DisplayInside::Flow => {
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// Whatever happened before, we just found an inline level element, so
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// all we need to do is to remember this ongoing inline level box.
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self.ongoing_inline_boxes_stack.push(InlineBox {
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style: style.clone(),
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first_fragment: true,
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last_fragment: false,
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children: vec![],
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});
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NonReplacedContents::traverse(non_replaced, &style, self.context, self);
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let mut inline_box = self
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.ongoing_inline_boxes_stack
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.pop()
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.expect("no ongoing inline level box found");
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inline_box.last_fragment = true;
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Arc::new(InlineLevelBox::InlineBox(inline_box))
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}
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DisplayInside::FlowRoot => {
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// a.k.a. `inline-block`
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unimplemented!()
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}
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},
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};
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self.current_inline_level_boxes().push(box_.clone());
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box_
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}
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fn handle_block_level_element(
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&mut self,
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style: Arc<ComputedValues>,
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display_inside: DisplayInside,
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contents: Contents,
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box_slot: BoxSlot<'a>,
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) {
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// We just found a block level element, all ongoing inline level boxes
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// need to be split around it. We iterate on the fragmented inline
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// level box stack to take their contents and set their first_fragment
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// field to false, for the fragmented inline level boxes that will
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// come after the block level element.
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let mut fragmented_inline_boxes =
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self.ongoing_inline_boxes_stack
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.iter_mut()
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.rev()
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.map(|ongoing| {
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let fragmented = InlineBox {
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style: ongoing.style.clone(),
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first_fragment: ongoing.first_fragment,
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// The fragmented boxes before the block level element
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// are obviously not the last fragment.
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last_fragment: false,
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children: take(&mut ongoing.children),
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};
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ongoing.first_fragment = false;
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fragmented
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});
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if let Some(last) = fragmented_inline_boxes.next() {
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// There were indeed some ongoing inline level boxes before
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// the block, we accumulate them as a single inline level box
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// to be pushed to the ongoing inline formatting context.
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let mut fragmented_inline = InlineLevelBox::InlineBox(last);
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for mut fragmented_parent_inline_box in fragmented_inline_boxes {
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fragmented_parent_inline_box
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.children
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.push(Arc::new(fragmented_inline));
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fragmented_inline = InlineLevelBox::InlineBox(fragmented_parent_inline_box);
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}
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self.ongoing_inline_formatting_context
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.inline_level_boxes
|
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.push(Arc::new(fragmented_inline));
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}
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// We found a block level element, so the ongoing inline formatting
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// context needs to be ended.
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self.end_ongoing_inline_formatting_context();
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let intermediate_box = match contents.try_into() {
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Ok(contents) => match display_inside {
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DisplayInside::Flow => IntermediateBlockLevelBox::SameFormattingContextBlock {
|
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style,
|
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contents: IntermediateBlockContainer::Deferred { contents },
|
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},
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_ => IntermediateBlockLevelBox::Independent {
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style,
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display_inside,
|
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contents: contents.into(),
|
||||
},
|
||||
},
|
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Err(contents) => {
|
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let contents = Contents::Replaced(contents);
|
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IntermediateBlockLevelBox::Independent {
|
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style,
|
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display_inside,
|
||||
contents,
|
||||
}
|
||||
}
|
||||
};
|
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self.block_level_boxes.push((intermediate_box, box_slot))
|
||||
}
|
||||
|
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fn handle_absolutely_positioned_element(
|
||||
&mut self,
|
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style: Arc<ComputedValues>,
|
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display_inside: DisplayInside,
|
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contents: Contents,
|
||||
box_slot: BoxSlot<'a>,
|
||||
) {
|
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if !self.has_ongoing_inline_formatting_context() {
|
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let box_ = IntermediateBlockLevelBox::OutOfFlowAbsolutelyPositionedBox {
|
||||
style,
|
||||
contents,
|
||||
display_inside,
|
||||
};
|
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self.block_level_boxes.push((box_, box_slot))
|
||||
} else {
|
||||
let box_ = Arc::new(InlineLevelBox::OutOfFlowAbsolutelyPositionedBox(
|
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AbsolutelyPositionedBox {
|
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contents: IndependentFormattingContext::construct(
|
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self.context,
|
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&style,
|
||||
display_inside,
|
||||
contents,
|
||||
),
|
||||
style,
|
||||
},
|
||||
));
|
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self.current_inline_level_boxes().push(box_.clone());
|
||||
box_slot.set(LayoutBox::InlineLevel(box_))
|
||||
}
|
||||
}
|
||||
|
||||
fn handle_float_element(
|
||||
&mut self,
|
||||
style: Arc<ComputedValues>,
|
||||
display_inside: DisplayInside,
|
||||
contents: Contents,
|
||||
box_slot: BoxSlot<'a>,
|
||||
) {
|
||||
self.contains_floats = ContainsFloats::Yes;
|
||||
|
||||
if !self.has_ongoing_inline_formatting_context() {
|
||||
let box_ = IntermediateBlockLevelBox::OutOfFlowFloatBox {
|
||||
style,
|
||||
contents,
|
||||
display_inside,
|
||||
};
|
||||
self.block_level_boxes.push((box_, box_slot));
|
||||
} else {
|
||||
let box_ = Arc::new(InlineLevelBox::OutOfFlowFloatBox(FloatBox {
|
||||
contents: IndependentFormattingContext::construct(
|
||||
self.context,
|
||||
&style,
|
||||
display_inside,
|
||||
contents,
|
||||
),
|
||||
style,
|
||||
}));
|
||||
self.current_inline_level_boxes().push(box_.clone());
|
||||
box_slot.set(LayoutBox::InlineLevel(box_))
|
||||
}
|
||||
}
|
||||
|
||||
fn end_ongoing_inline_formatting_context(&mut self) {
|
||||
assert!(
|
||||
self.ongoing_inline_boxes_stack.is_empty(),
|
||||
"there should be no ongoing inline level boxes",
|
||||
);
|
||||
|
||||
if self
|
||||
.ongoing_inline_formatting_context
|
||||
.inline_level_boxes
|
||||
.is_empty()
|
||||
{
|
||||
// There should never be an empty inline formatting context.
|
||||
return;
|
||||
}
|
||||
|
||||
let block_container_style = self.block_container_style;
|
||||
let anonymous_style = self.anonymous_style.get_or_insert_with(|| {
|
||||
// If parent_style is None, the parent is the document node,
|
||||
// in which case anonymous inline boxes should inherit their
|
||||
// styles from initial values.
|
||||
ComputedValues::anonymous_inheriting_from(Some(block_container_style))
|
||||
});
|
||||
|
||||
let box_ = IntermediateBlockLevelBox::SameFormattingContextBlock {
|
||||
style: anonymous_style.clone(),
|
||||
contents: IntermediateBlockContainer::InlineFormattingContext(take(
|
||||
&mut self.ongoing_inline_formatting_context,
|
||||
)),
|
||||
};
|
||||
self.block_level_boxes.push((box_, BoxSlot::dummy()))
|
||||
}
|
||||
|
||||
fn current_inline_level_boxes(&mut self) -> &mut Vec<Arc<InlineLevelBox>> {
|
||||
match self.ongoing_inline_boxes_stack.last_mut() {
|
||||
Some(last) => &mut last.children,
|
||||
None => &mut self.ongoing_inline_formatting_context.inline_level_boxes,
|
||||
}
|
||||
}
|
||||
|
||||
fn has_ongoing_inline_formatting_context(&self) -> bool {
|
||||
!self
|
||||
.ongoing_inline_formatting_context
|
||||
.inline_level_boxes
|
||||
.is_empty()
|
||||
|| !self.ongoing_inline_boxes_stack.is_empty()
|
||||
}
|
||||
}
|
||||
|
||||
impl IntermediateBlockLevelBox {
|
||||
fn finish(self, context: &Context) -> (Arc<BlockLevelBox>, ContainsFloats) {
|
||||
match self {
|
||||
IntermediateBlockLevelBox::SameFormattingContextBlock { style, contents } => {
|
||||
let (contents, contains_floats) = contents.finish(context, &style);
|
||||
let block_level_box =
|
||||
Arc::new(BlockLevelBox::SameFormattingContextBlock { contents, style });
|
||||
(block_level_box, contains_floats)
|
||||
}
|
||||
IntermediateBlockLevelBox::Independent {
|
||||
style,
|
||||
display_inside,
|
||||
contents,
|
||||
} => {
|
||||
let contents = IndependentFormattingContext::construct(
|
||||
context,
|
||||
&style,
|
||||
display_inside,
|
||||
contents,
|
||||
);
|
||||
(
|
||||
Arc::new(BlockLevelBox::Independent { style, contents }),
|
||||
ContainsFloats::No,
|
||||
)
|
||||
}
|
||||
IntermediateBlockLevelBox::OutOfFlowAbsolutelyPositionedBox {
|
||||
style,
|
||||
display_inside,
|
||||
contents,
|
||||
} => {
|
||||
let block_level_box = Arc::new(BlockLevelBox::OutOfFlowAbsolutelyPositionedBox(
|
||||
AbsolutelyPositionedBox {
|
||||
contents: IndependentFormattingContext::construct(
|
||||
context,
|
||||
&style,
|
||||
display_inside,
|
||||
contents,
|
||||
),
|
||||
style: style,
|
||||
},
|
||||
));
|
||||
(block_level_box, ContainsFloats::No)
|
||||
}
|
||||
IntermediateBlockLevelBox::OutOfFlowFloatBox {
|
||||
style,
|
||||
display_inside,
|
||||
contents,
|
||||
} => {
|
||||
let contents = IndependentFormattingContext::construct(
|
||||
context,
|
||||
&style,
|
||||
display_inside,
|
||||
contents,
|
||||
);
|
||||
let block_level_box = Arc::new(BlockLevelBox::OutOfFlowFloatBox(FloatBox {
|
||||
contents,
|
||||
style,
|
||||
}));
|
||||
(block_level_box, ContainsFloats::Yes)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl IntermediateBlockContainer {
|
||||
fn finish(
|
||||
self,
|
||||
context: &Context,
|
||||
style: &Arc<ComputedValues>,
|
||||
) -> (BlockContainer, ContainsFloats) {
|
||||
match self {
|
||||
IntermediateBlockContainer::Deferred { contents } => {
|
||||
BlockContainer::construct(context, style, contents)
|
||||
}
|
||||
IntermediateBlockContainer::InlineFormattingContext(ifc) => {
|
||||
// If that inline formatting context contained any float, those
|
||||
// were already taken into account during the first phase of
|
||||
// box construction.
|
||||
(
|
||||
BlockContainer::InlineFormattingContext(ifc),
|
||||
ContainsFloats::No,
|
||||
)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
|
||||
pub(in crate::layout) enum ContainsFloats {
|
||||
No,
|
||||
Yes,
|
||||
}
|
||||
|
||||
impl std::ops::BitOrAssign for ContainsFloats {
|
||||
fn bitor_assign(&mut self, other: Self) {
|
||||
if other == ContainsFloats::Yes {
|
||||
*self = ContainsFloats::Yes;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl Default for ContainsFloats {
|
||||
fn default() -> Self {
|
||||
ContainsFloats::No
|
||||
}
|
||||
}
|
||||
18
components/layout_2020/flow/float.rs
Normal file
18
components/layout_2020/flow/float.rs
Normal file
|
|
@ -0,0 +1,18 @@
|
|||
use super::*;
|
||||
|
||||
#[derive(Debug)]
|
||||
pub(in crate::layout) struct FloatBox {
|
||||
pub style: Arc<ComputedValues>,
|
||||
pub contents: IndependentFormattingContext,
|
||||
}
|
||||
|
||||
/// Data kept during layout about the floats in a given block formatting context.
|
||||
pub(in crate::layout) struct FloatContext {
|
||||
// TODO
|
||||
}
|
||||
|
||||
impl FloatContext {
|
||||
pub fn new() -> Self {
|
||||
FloatContext {}
|
||||
}
|
||||
}
|
||||
345
components/layout_2020/flow/inline.rs
Normal file
345
components/layout_2020/flow/inline.rs
Normal file
|
|
@ -0,0 +1,345 @@
|
|||
use super::*;
|
||||
use crate::fonts::BITSTREAM_VERA_SANS;
|
||||
use crate::text::ShapedSegment;
|
||||
|
||||
#[derive(Debug, Default)]
|
||||
pub(in crate::layout) struct InlineFormattingContext {
|
||||
pub(super) inline_level_boxes: Vec<Arc<InlineLevelBox>>,
|
||||
}
|
||||
|
||||
#[derive(Debug)]
|
||||
pub(in crate::layout) enum InlineLevelBox {
|
||||
InlineBox(InlineBox),
|
||||
TextRun(TextRun),
|
||||
OutOfFlowAbsolutelyPositionedBox(AbsolutelyPositionedBox),
|
||||
OutOfFlowFloatBox(FloatBox),
|
||||
Atomic {
|
||||
style: Arc<ComputedValues>,
|
||||
// FIXME: this should be IndependentFormattingContext:
|
||||
contents: ReplacedContent,
|
||||
},
|
||||
}
|
||||
|
||||
#[derive(Debug)]
|
||||
pub(in crate::layout) struct InlineBox {
|
||||
pub style: Arc<ComputedValues>,
|
||||
pub first_fragment: bool,
|
||||
pub last_fragment: bool,
|
||||
pub children: Vec<Arc<InlineLevelBox>>,
|
||||
}
|
||||
|
||||
/// https://www.w3.org/TR/css-display-3/#css-text-run
|
||||
#[derive(Debug)]
|
||||
pub(in crate::layout) struct TextRun {
|
||||
pub parent_style: Arc<ComputedValues>,
|
||||
pub text: String,
|
||||
}
|
||||
|
||||
struct InlineNestingLevelState<'box_tree> {
|
||||
remaining_boxes: std::slice::Iter<'box_tree, Arc<InlineLevelBox>>,
|
||||
fragments_so_far: Vec<Fragment>,
|
||||
inline_start: Length,
|
||||
max_block_size_of_fragments_so_far: Length,
|
||||
}
|
||||
|
||||
struct PartialInlineBoxFragment<'box_tree> {
|
||||
style: Arc<ComputedValues>,
|
||||
start_corner: Vec2<Length>,
|
||||
padding: Sides<Length>,
|
||||
border: Sides<Length>,
|
||||
margin: Sides<Length>,
|
||||
last_box_tree_fragment: bool,
|
||||
parent_nesting_level: InlineNestingLevelState<'box_tree>,
|
||||
}
|
||||
|
||||
struct InlineFormattingContextState<'box_tree, 'cb> {
|
||||
containing_block: &'cb ContainingBlock,
|
||||
line_boxes: LinesBoxes,
|
||||
inline_position: Length,
|
||||
partial_inline_boxes_stack: Vec<PartialInlineBoxFragment<'box_tree>>,
|
||||
current_nesting_level: InlineNestingLevelState<'box_tree>,
|
||||
}
|
||||
|
||||
struct LinesBoxes {
|
||||
boxes: Vec<Fragment>,
|
||||
next_line_block_position: Length,
|
||||
}
|
||||
|
||||
impl InlineFormattingContext {
|
||||
pub(super) fn layout<'a>(
|
||||
&'a self,
|
||||
containing_block: &ContainingBlock,
|
||||
tree_rank: usize,
|
||||
absolutely_positioned_fragments: &mut Vec<AbsolutelyPositionedFragment<'a>>,
|
||||
) -> FlowChildren {
|
||||
let mut ifc = InlineFormattingContextState {
|
||||
containing_block,
|
||||
partial_inline_boxes_stack: Vec::new(),
|
||||
line_boxes: LinesBoxes {
|
||||
boxes: Vec::new(),
|
||||
next_line_block_position: Length::zero(),
|
||||
},
|
||||
inline_position: Length::zero(),
|
||||
current_nesting_level: InlineNestingLevelState {
|
||||
remaining_boxes: self.inline_level_boxes.iter(),
|
||||
fragments_so_far: Vec::with_capacity(self.inline_level_boxes.len()),
|
||||
inline_start: Length::zero(),
|
||||
max_block_size_of_fragments_so_far: Length::zero(),
|
||||
},
|
||||
};
|
||||
loop {
|
||||
if let Some(child) = ifc.current_nesting_level.remaining_boxes.next() {
|
||||
match &**child {
|
||||
InlineLevelBox::InlineBox(inline) => {
|
||||
let partial = inline.start_layout(&mut ifc);
|
||||
ifc.partial_inline_boxes_stack.push(partial)
|
||||
}
|
||||
InlineLevelBox::TextRun(run) => run.layout(&mut ifc),
|
||||
InlineLevelBox::Atomic { style: _, contents } => {
|
||||
// FIXME
|
||||
match *contents {}
|
||||
}
|
||||
InlineLevelBox::OutOfFlowAbsolutelyPositionedBox(box_) => {
|
||||
let initial_start_corner = match box_.style.specified_display {
|
||||
Display::GeneratingBox(DisplayGeneratingBox::OutsideInside {
|
||||
outside,
|
||||
inside: _,
|
||||
}) => Vec2 {
|
||||
inline: match outside {
|
||||
DisplayOutside::Inline => ifc.inline_position,
|
||||
DisplayOutside::Block => Length::zero(),
|
||||
},
|
||||
block: ifc.line_boxes.next_line_block_position,
|
||||
},
|
||||
Display::Contents => {
|
||||
panic!("display:contents does not generate an abspos box")
|
||||
}
|
||||
Display::None => panic!("display:none does not generate an abspos box"),
|
||||
};
|
||||
absolutely_positioned_fragments
|
||||
.push(box_.layout(initial_start_corner, tree_rank));
|
||||
}
|
||||
InlineLevelBox::OutOfFlowFloatBox(_box_) => {
|
||||
// TODO
|
||||
continue;
|
||||
}
|
||||
}
|
||||
} else
|
||||
// Reached the end of ifc.remaining_boxes
|
||||
if let Some(mut partial) = ifc.partial_inline_boxes_stack.pop() {
|
||||
partial.finish_layout(
|
||||
&mut ifc.current_nesting_level,
|
||||
&mut ifc.inline_position,
|
||||
false,
|
||||
);
|
||||
ifc.current_nesting_level = partial.parent_nesting_level
|
||||
} else {
|
||||
ifc.line_boxes
|
||||
.finish_line(&mut ifc.current_nesting_level, containing_block);
|
||||
return FlowChildren {
|
||||
fragments: ifc.line_boxes.boxes,
|
||||
block_size: ifc.line_boxes.next_line_block_position,
|
||||
collapsible_margins_in_children: CollapsedBlockMargins::zero(),
|
||||
};
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl LinesBoxes {
|
||||
fn finish_line(
|
||||
&mut self,
|
||||
top_nesting_level: &mut InlineNestingLevelState,
|
||||
containing_block: &ContainingBlock,
|
||||
) {
|
||||
let start_corner = Vec2 {
|
||||
inline: Length::zero(),
|
||||
block: self.next_line_block_position,
|
||||
};
|
||||
let size = Vec2 {
|
||||
inline: containing_block.inline_size,
|
||||
block: std::mem::replace(
|
||||
&mut top_nesting_level.max_block_size_of_fragments_so_far,
|
||||
Length::zero(),
|
||||
),
|
||||
};
|
||||
self.next_line_block_position += size.block;
|
||||
self.boxes.push(Fragment::Anonymous(AnonymousFragment {
|
||||
children: take(&mut top_nesting_level.fragments_so_far),
|
||||
rect: Rect { start_corner, size },
|
||||
mode: containing_block.mode,
|
||||
}))
|
||||
}
|
||||
}
|
||||
|
||||
impl InlineBox {
|
||||
fn start_layout<'box_tree>(
|
||||
&'box_tree self,
|
||||
ifc: &mut InlineFormattingContextState<'box_tree, '_>,
|
||||
) -> PartialInlineBoxFragment<'box_tree> {
|
||||
let style = self.style.clone();
|
||||
let cbis = ifc.containing_block.inline_size;
|
||||
let mut padding = style.padding().percentages_relative_to(cbis);
|
||||
let mut border = style.border_width().percentages_relative_to(cbis);
|
||||
let mut margin = style
|
||||
.margin()
|
||||
.percentages_relative_to(cbis)
|
||||
.auto_is(Length::zero);
|
||||
if self.first_fragment {
|
||||
ifc.inline_position += padding.inline_start + border.inline_start + margin.inline_start;
|
||||
} else {
|
||||
padding.inline_start = Length::zero();
|
||||
border.inline_start = Length::zero();
|
||||
margin.inline_start = Length::zero();
|
||||
}
|
||||
let mut start_corner = Vec2 {
|
||||
block: padding.block_start + border.block_start + margin.block_start,
|
||||
inline: ifc.inline_position - ifc.current_nesting_level.inline_start,
|
||||
};
|
||||
start_corner += &relative_adjustement(
|
||||
&style,
|
||||
ifc.containing_block.inline_size,
|
||||
ifc.containing_block.block_size,
|
||||
);
|
||||
PartialInlineBoxFragment {
|
||||
style,
|
||||
start_corner,
|
||||
padding,
|
||||
border,
|
||||
margin,
|
||||
last_box_tree_fragment: self.last_fragment,
|
||||
parent_nesting_level: std::mem::replace(
|
||||
&mut ifc.current_nesting_level,
|
||||
InlineNestingLevelState {
|
||||
remaining_boxes: self.children.iter(),
|
||||
fragments_so_far: Vec::with_capacity(self.children.len()),
|
||||
inline_start: ifc.inline_position,
|
||||
max_block_size_of_fragments_so_far: Length::zero(),
|
||||
},
|
||||
),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
impl<'box_tree> PartialInlineBoxFragment<'box_tree> {
|
||||
fn finish_layout(
|
||||
&mut self,
|
||||
nesting_level: &mut InlineNestingLevelState,
|
||||
inline_position: &mut Length,
|
||||
at_line_break: bool,
|
||||
) {
|
||||
let mut fragment = BoxFragment {
|
||||
style: self.style.clone(),
|
||||
children: take(&mut nesting_level.fragments_so_far),
|
||||
content_rect: Rect {
|
||||
size: Vec2 {
|
||||
inline: *inline_position - self.start_corner.inline,
|
||||
block: nesting_level.max_block_size_of_fragments_so_far,
|
||||
},
|
||||
start_corner: self.start_corner.clone(),
|
||||
},
|
||||
padding: self.padding.clone(),
|
||||
border: self.border.clone(),
|
||||
margin: self.margin.clone(),
|
||||
block_margins_collapsed_with_children: CollapsedBlockMargins::zero(),
|
||||
};
|
||||
let last_fragment = self.last_box_tree_fragment && !at_line_break;
|
||||
if last_fragment {
|
||||
*inline_position += fragment.padding.inline_end
|
||||
+ fragment.border.inline_end
|
||||
+ fragment.margin.inline_end;
|
||||
} else {
|
||||
fragment.padding.inline_end = Length::zero();
|
||||
fragment.border.inline_end = Length::zero();
|
||||
fragment.margin.inline_end = Length::zero();
|
||||
}
|
||||
self.parent_nesting_level
|
||||
.max_block_size_of_fragments_so_far
|
||||
.max_assign(
|
||||
fragment.content_rect.size.block
|
||||
+ fragment.padding.block_sum()
|
||||
+ fragment.border.block_sum()
|
||||
+ fragment.margin.block_sum(),
|
||||
);
|
||||
self.parent_nesting_level
|
||||
.fragments_so_far
|
||||
.push(Fragment::Box(fragment));
|
||||
}
|
||||
}
|
||||
|
||||
impl TextRun {
|
||||
fn layout(&self, ifc: &mut InlineFormattingContextState) {
|
||||
let available = ifc.containing_block.inline_size - ifc.inline_position;
|
||||
let mut chars = self.text.chars();
|
||||
loop {
|
||||
let mut shaped = ShapedSegment::new_with_naive_shaping(BITSTREAM_VERA_SANS.clone());
|
||||
let mut last_break_opportunity = None;
|
||||
loop {
|
||||
let next = chars.next();
|
||||
if matches!(next, Some(' ') | None) {
|
||||
let inline_size = self.parent_style.font.font_size * shaped.advance_width;
|
||||
if inline_size > available {
|
||||
if let Some((state, iter)) = last_break_opportunity.take() {
|
||||
shaped.restore(&state);
|
||||
chars = iter;
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
if let Some(ch) = next {
|
||||
if ch == ' ' {
|
||||
last_break_opportunity = Some((shaped.save(), chars.clone()))
|
||||
}
|
||||
shaped.append_char(ch).unwrap()
|
||||
} else {
|
||||
break;
|
||||
}
|
||||
}
|
||||
let inline_size = self.parent_style.font.font_size * shaped.advance_width;
|
||||
// https://www.w3.org/TR/CSS2/visudet.html#propdef-line-height
|
||||
// 'normal':
|
||||
// “set the used value to a "reasonable" value based on the font of the element.”
|
||||
let line_height = self.parent_style.font.font_size.0 * 1.2;
|
||||
let content_rect = Rect {
|
||||
start_corner: Vec2 {
|
||||
block: Length::zero(),
|
||||
inline: ifc.inline_position - ifc.current_nesting_level.inline_start,
|
||||
},
|
||||
size: Vec2 {
|
||||
block: line_height,
|
||||
inline: inline_size,
|
||||
},
|
||||
};
|
||||
ifc.inline_position += inline_size;
|
||||
ifc.current_nesting_level
|
||||
.max_block_size_of_fragments_so_far
|
||||
.max_assign(line_height);
|
||||
ifc.current_nesting_level
|
||||
.fragments_so_far
|
||||
.push(Fragment::Text(TextFragment {
|
||||
parent_style: self.parent_style.clone(),
|
||||
content_rect,
|
||||
text: shaped,
|
||||
}));
|
||||
if chars.as_str().is_empty() {
|
||||
break;
|
||||
} else {
|
||||
// New line
|
||||
ifc.current_nesting_level.inline_start = Length::zero();
|
||||
let mut nesting_level = &mut ifc.current_nesting_level;
|
||||
for partial in ifc.partial_inline_boxes_stack.iter_mut().rev() {
|
||||
partial.finish_layout(nesting_level, &mut ifc.inline_position, true);
|
||||
partial.start_corner.inline = Length::zero();
|
||||
partial.padding.inline_start = Length::zero();
|
||||
partial.border.inline_start = Length::zero();
|
||||
partial.margin.inline_start = Length::zero();
|
||||
partial.parent_nesting_level.inline_start = Length::zero();
|
||||
nesting_level = &mut partial.parent_nesting_level;
|
||||
}
|
||||
ifc.line_boxes
|
||||
.finish_line(nesting_level, ifc.containing_block);
|
||||
ifc.inline_position = Length::zero();
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
439
components/layout_2020/flow/mod.rs
Normal file
439
components/layout_2020/flow/mod.rs
Normal file
|
|
@ -0,0 +1,439 @@
|
|||
//! Flow layout, also known as block-and-inline layout.
|
||||
|
||||
use super::*;
|
||||
use rayon::prelude::*;
|
||||
use rayon_croissant::ParallelIteratorExt;
|
||||
|
||||
mod construct;
|
||||
mod float;
|
||||
mod inline;
|
||||
mod root;
|
||||
|
||||
pub(super) use construct::*;
|
||||
pub(super) use float::*;
|
||||
pub(super) use inline::*;
|
||||
|
||||
#[derive(Debug)]
|
||||
pub(super) struct BlockFormattingContext {
|
||||
pub contents: BlockContainer,
|
||||
pub contains_floats: bool,
|
||||
}
|
||||
|
||||
#[derive(Debug)]
|
||||
pub(super) enum BlockContainer {
|
||||
BlockLevelBoxes(Vec<Arc<BlockLevelBox>>),
|
||||
InlineFormattingContext(InlineFormattingContext),
|
||||
}
|
||||
|
||||
#[derive(Debug)]
|
||||
pub(super) enum BlockLevelBox {
|
||||
SameFormattingContextBlock {
|
||||
style: Arc<ComputedValues>,
|
||||
contents: BlockContainer,
|
||||
},
|
||||
OutOfFlowAbsolutelyPositionedBox(AbsolutelyPositionedBox),
|
||||
OutOfFlowFloatBox(FloatBox),
|
||||
Independent {
|
||||
style: Arc<ComputedValues>,
|
||||
contents: IndependentFormattingContext,
|
||||
},
|
||||
}
|
||||
|
||||
pub(super) struct FlowChildren {
|
||||
pub fragments: Vec<Fragment>,
|
||||
pub block_size: Length,
|
||||
pub collapsible_margins_in_children: CollapsedBlockMargins,
|
||||
}
|
||||
|
||||
#[derive(Clone, Copy)]
|
||||
struct CollapsibleWithParentStartMargin(bool);
|
||||
|
||||
impl BlockFormattingContext {
|
||||
pub(super) fn layout<'a>(
|
||||
&'a self,
|
||||
containing_block: &ContainingBlock,
|
||||
tree_rank: usize,
|
||||
absolutely_positioned_fragments: &mut Vec<AbsolutelyPositionedFragment<'a>>,
|
||||
) -> FlowChildren {
|
||||
let mut float_context;
|
||||
let float_context = if self.contains_floats {
|
||||
float_context = FloatContext::new();
|
||||
Some(&mut float_context)
|
||||
} else {
|
||||
None
|
||||
};
|
||||
let mut flow_children = self.contents.layout(
|
||||
containing_block,
|
||||
tree_rank,
|
||||
absolutely_positioned_fragments,
|
||||
float_context,
|
||||
CollapsibleWithParentStartMargin(false),
|
||||
);
|
||||
flow_children.block_size += flow_children.collapsible_margins_in_children.end.solve();
|
||||
flow_children
|
||||
.collapsible_margins_in_children
|
||||
.collapsed_through = false;
|
||||
flow_children.collapsible_margins_in_children.end = CollapsedMargin::zero();
|
||||
flow_children
|
||||
}
|
||||
}
|
||||
|
||||
impl BlockContainer {
|
||||
fn layout<'a>(
|
||||
&'a self,
|
||||
containing_block: &ContainingBlock,
|
||||
tree_rank: usize,
|
||||
absolutely_positioned_fragments: &mut Vec<AbsolutelyPositionedFragment<'a>>,
|
||||
float_context: Option<&mut FloatContext>,
|
||||
collapsible_with_parent_start_margin: CollapsibleWithParentStartMargin,
|
||||
) -> FlowChildren {
|
||||
match self {
|
||||
BlockContainer::BlockLevelBoxes(child_boxes) => layout_block_level_children(
|
||||
child_boxes,
|
||||
containing_block,
|
||||
tree_rank,
|
||||
absolutely_positioned_fragments,
|
||||
float_context,
|
||||
collapsible_with_parent_start_margin,
|
||||
),
|
||||
BlockContainer::InlineFormattingContext(ifc) => {
|
||||
ifc.layout(containing_block, tree_rank, absolutely_positioned_fragments)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn layout_block_level_children<'a>(
|
||||
child_boxes: &'a [Arc<BlockLevelBox>],
|
||||
containing_block: &ContainingBlock,
|
||||
tree_rank: usize,
|
||||
absolutely_positioned_fragments: &mut Vec<AbsolutelyPositionedFragment<'a>>,
|
||||
float_context: Option<&mut FloatContext>,
|
||||
collapsible_with_parent_start_margin: CollapsibleWithParentStartMargin,
|
||||
) -> FlowChildren {
|
||||
fn place_block_level_fragment(fragment: &mut Fragment, placement_state: &mut PlacementState) {
|
||||
match fragment {
|
||||
Fragment::Box(fragment) => {
|
||||
let fragment_block_margins = &fragment.block_margins_collapsed_with_children;
|
||||
let fragment_block_size = fragment.padding.block_sum()
|
||||
+ fragment.border.block_sum()
|
||||
+ fragment.content_rect.size.block;
|
||||
|
||||
if placement_state.next_in_flow_margin_collapses_with_parent_start_margin {
|
||||
assert_eq!(placement_state.current_margin.solve(), Length::zero());
|
||||
placement_state
|
||||
.start_margin
|
||||
.adjoin_assign(&fragment_block_margins.start);
|
||||
if fragment_block_margins.collapsed_through {
|
||||
placement_state
|
||||
.start_margin
|
||||
.adjoin_assign(&fragment_block_margins.end);
|
||||
return;
|
||||
}
|
||||
placement_state.next_in_flow_margin_collapses_with_parent_start_margin = false;
|
||||
} else {
|
||||
placement_state
|
||||
.current_margin
|
||||
.adjoin_assign(&fragment_block_margins.start);
|
||||
}
|
||||
fragment.content_rect.start_corner.block += placement_state.current_margin.solve()
|
||||
+ placement_state.current_block_direction_position;
|
||||
if fragment_block_margins.collapsed_through {
|
||||
placement_state
|
||||
.current_margin
|
||||
.adjoin_assign(&fragment_block_margins.end);
|
||||
return;
|
||||
}
|
||||
placement_state.current_block_direction_position +=
|
||||
placement_state.current_margin.solve() + fragment_block_size;
|
||||
placement_state.current_margin = fragment_block_margins.end;
|
||||
}
|
||||
Fragment::Anonymous(fragment) => {
|
||||
// FIXME(nox): Margin collapsing for hypothetical boxes of
|
||||
// abspos elements is probably wrong.
|
||||
assert!(fragment.children.is_empty());
|
||||
assert_eq!(fragment.rect.size.block, Length::zero());
|
||||
fragment.rect.start_corner.block +=
|
||||
placement_state.current_block_direction_position;
|
||||
}
|
||||
_ => unreachable!(),
|
||||
}
|
||||
}
|
||||
|
||||
struct PlacementState {
|
||||
next_in_flow_margin_collapses_with_parent_start_margin: bool,
|
||||
start_margin: CollapsedMargin,
|
||||
current_margin: CollapsedMargin,
|
||||
current_block_direction_position: Length,
|
||||
}
|
||||
|
||||
let abspos_so_far = absolutely_positioned_fragments.len();
|
||||
let mut placement_state = PlacementState {
|
||||
next_in_flow_margin_collapses_with_parent_start_margin:
|
||||
collapsible_with_parent_start_margin.0,
|
||||
start_margin: CollapsedMargin::zero(),
|
||||
current_margin: CollapsedMargin::zero(),
|
||||
current_block_direction_position: Length::zero(),
|
||||
};
|
||||
let mut fragments: Vec<_>;
|
||||
if let Some(float_context) = float_context {
|
||||
// Because floats are involved, we do layout for this block formatting context
|
||||
// in tree order without parallelism. This enables mutable access
|
||||
// to a `FloatContext` that tracks every float encountered so far (again in tree order).
|
||||
fragments = child_boxes
|
||||
.iter()
|
||||
.enumerate()
|
||||
.map(|(tree_rank, box_)| {
|
||||
let mut fragment = box_.layout(
|
||||
containing_block,
|
||||
tree_rank,
|
||||
absolutely_positioned_fragments,
|
||||
Some(float_context),
|
||||
);
|
||||
place_block_level_fragment(&mut fragment, &mut placement_state);
|
||||
fragment
|
||||
})
|
||||
.collect()
|
||||
} else {
|
||||
fragments = child_boxes
|
||||
.par_iter()
|
||||
.enumerate()
|
||||
.mapfold_reduce_into(
|
||||
absolutely_positioned_fragments,
|
||||
|abspos_fragments, (tree_rank, box_)| {
|
||||
box_.layout(
|
||||
containing_block,
|
||||
tree_rank,
|
||||
abspos_fragments,
|
||||
/* float_context = */ None,
|
||||
)
|
||||
},
|
||||
|left_abspos_fragments, mut right_abspos_fragments| {
|
||||
left_abspos_fragments.append(&mut right_abspos_fragments);
|
||||
},
|
||||
)
|
||||
.collect();
|
||||
for fragment in &mut fragments {
|
||||
place_block_level_fragment(fragment, &mut placement_state)
|
||||
}
|
||||
}
|
||||
|
||||
adjust_static_positions(
|
||||
&mut absolutely_positioned_fragments[abspos_so_far..],
|
||||
&mut fragments,
|
||||
tree_rank,
|
||||
);
|
||||
|
||||
FlowChildren {
|
||||
fragments,
|
||||
block_size: placement_state.current_block_direction_position,
|
||||
collapsible_margins_in_children: CollapsedBlockMargins {
|
||||
collapsed_through: placement_state
|
||||
.next_in_flow_margin_collapses_with_parent_start_margin,
|
||||
start: placement_state.start_margin,
|
||||
end: placement_state.current_margin,
|
||||
},
|
||||
}
|
||||
}
|
||||
|
||||
impl BlockLevelBox {
|
||||
fn layout<'a>(
|
||||
&'a self,
|
||||
containing_block: &ContainingBlock,
|
||||
tree_rank: usize,
|
||||
absolutely_positioned_fragments: &mut Vec<AbsolutelyPositionedFragment<'a>>,
|
||||
float_context: Option<&mut FloatContext>,
|
||||
) -> Fragment {
|
||||
match self {
|
||||
BlockLevelBox::SameFormattingContextBlock { style, contents } => {
|
||||
Fragment::Box(layout_in_flow_non_replaced_block_level(
|
||||
containing_block,
|
||||
absolutely_positioned_fragments,
|
||||
style,
|
||||
BlockLevelKind::SameFormattingContextBlock,
|
||||
|containing_block, nested_abspos, collapsible_with_parent_start_margin| {
|
||||
contents.layout(
|
||||
containing_block,
|
||||
tree_rank,
|
||||
nested_abspos,
|
||||
float_context,
|
||||
collapsible_with_parent_start_margin,
|
||||
)
|
||||
},
|
||||
))
|
||||
}
|
||||
BlockLevelBox::Independent { style, contents } => match contents.as_replaced() {
|
||||
Ok(replaced) => {
|
||||
// FIXME
|
||||
match *replaced {}
|
||||
}
|
||||
Err(contents) => Fragment::Box(layout_in_flow_non_replaced_block_level(
|
||||
containing_block,
|
||||
absolutely_positioned_fragments,
|
||||
style,
|
||||
BlockLevelKind::EstablishesAnIndependentFormattingContext,
|
||||
|containing_block, nested_abspos, _| {
|
||||
contents.layout(containing_block, tree_rank, nested_abspos)
|
||||
},
|
||||
)),
|
||||
},
|
||||
BlockLevelBox::OutOfFlowAbsolutelyPositionedBox(box_) => {
|
||||
absolutely_positioned_fragments.push(box_.layout(Vec2::zero(), tree_rank));
|
||||
Fragment::Anonymous(AnonymousFragment::no_op(containing_block.mode))
|
||||
}
|
||||
BlockLevelBox::OutOfFlowFloatBox(_box_) => {
|
||||
// TODO
|
||||
Fragment::Anonymous(AnonymousFragment::no_op(containing_block.mode))
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
#[derive(PartialEq)]
|
||||
enum BlockLevelKind {
|
||||
SameFormattingContextBlock,
|
||||
EstablishesAnIndependentFormattingContext,
|
||||
}
|
||||
|
||||
/// https://drafts.csswg.org/css2/visudet.html#blockwidth
|
||||
/// https://drafts.csswg.org/css2/visudet.html#normal-block
|
||||
fn layout_in_flow_non_replaced_block_level<'a>(
|
||||
containing_block: &ContainingBlock,
|
||||
absolutely_positioned_fragments: &mut Vec<AbsolutelyPositionedFragment<'a>>,
|
||||
style: &Arc<ComputedValues>,
|
||||
block_level_kind: BlockLevelKind,
|
||||
layout_contents: impl FnOnce(
|
||||
&ContainingBlock,
|
||||
&mut Vec<AbsolutelyPositionedFragment<'a>>,
|
||||
CollapsibleWithParentStartMargin,
|
||||
) -> FlowChildren,
|
||||
) -> BoxFragment {
|
||||
let cbis = containing_block.inline_size;
|
||||
let padding = style.padding().percentages_relative_to(cbis);
|
||||
let border = style.border_width().percentages_relative_to(cbis);
|
||||
let mut computed_margin = style.margin().percentages_relative_to(cbis);
|
||||
let pb = &padding + &border;
|
||||
let box_size = style.box_size();
|
||||
let inline_size = box_size.inline.percentage_relative_to(cbis);
|
||||
if let LengthOrAuto::Length(is) = inline_size {
|
||||
let inline_margins = cbis - is - pb.inline_sum();
|
||||
use LengthOrAuto::*;
|
||||
match (
|
||||
&mut computed_margin.inline_start,
|
||||
&mut computed_margin.inline_end,
|
||||
) {
|
||||
(s @ &mut Auto, e @ &mut Auto) => {
|
||||
*s = Length(inline_margins / 2.);
|
||||
*e = Length(inline_margins / 2.);
|
||||
}
|
||||
(s @ &mut Auto, _) => {
|
||||
*s = Length(inline_margins);
|
||||
}
|
||||
(_, e @ &mut Auto) => {
|
||||
*e = Length(inline_margins);
|
||||
}
|
||||
(_, e @ _) => {
|
||||
// Either the inline-end margin is auto,
|
||||
// or we’re over-constrained and we do as if it were.
|
||||
*e = Length(inline_margins);
|
||||
}
|
||||
}
|
||||
}
|
||||
let margin = computed_margin.auto_is(Length::zero);
|
||||
let mut block_margins_collapsed_with_children = CollapsedBlockMargins::from_margin(&margin);
|
||||
let inline_size = inline_size.auto_is(|| cbis - pb.inline_sum() - margin.inline_sum());
|
||||
let block_size = match box_size.block {
|
||||
LengthOrPercentageOrAuto::Length(l) => LengthOrAuto::Length(l),
|
||||
LengthOrPercentageOrAuto::Percentage(p) => containing_block.block_size.map(|cbbs| cbbs * p),
|
||||
LengthOrPercentageOrAuto::Auto => LengthOrAuto::Auto,
|
||||
};
|
||||
let containing_block_for_children = ContainingBlock {
|
||||
inline_size,
|
||||
block_size,
|
||||
mode: style.writing_mode(),
|
||||
};
|
||||
// https://drafts.csswg.org/css-writing-modes/#orthogonal-flows
|
||||
assert_eq!(
|
||||
containing_block.mode, containing_block_for_children.mode,
|
||||
"Mixed writing modes are not supported yet"
|
||||
);
|
||||
let this_start_margin_can_collapse_with_children = CollapsibleWithParentStartMargin(
|
||||
block_level_kind == BlockLevelKind::SameFormattingContextBlock
|
||||
&& pb.block_start == Length::zero(),
|
||||
);
|
||||
let this_end_margin_can_collapse_with_children = (block_level_kind, pb.block_end, block_size)
|
||||
== (
|
||||
BlockLevelKind::SameFormattingContextBlock,
|
||||
Length::zero(),
|
||||
LengthOrAuto::Auto,
|
||||
);
|
||||
let mut nested_abspos = vec![];
|
||||
let mut flow_children = layout_contents(
|
||||
&containing_block_for_children,
|
||||
if style.box_.position.is_relatively_positioned() {
|
||||
&mut nested_abspos
|
||||
} else {
|
||||
absolutely_positioned_fragments
|
||||
},
|
||||
this_start_margin_can_collapse_with_children,
|
||||
);
|
||||
if this_start_margin_can_collapse_with_children.0 {
|
||||
block_margins_collapsed_with_children
|
||||
.start
|
||||
.adjoin_assign(&flow_children.collapsible_margins_in_children.start);
|
||||
if flow_children
|
||||
.collapsible_margins_in_children
|
||||
.collapsed_through
|
||||
{
|
||||
block_margins_collapsed_with_children
|
||||
.start
|
||||
.adjoin_assign(&std::mem::replace(
|
||||
&mut flow_children.collapsible_margins_in_children.end,
|
||||
CollapsedMargin::zero(),
|
||||
));
|
||||
}
|
||||
}
|
||||
if this_end_margin_can_collapse_with_children {
|
||||
block_margins_collapsed_with_children
|
||||
.end
|
||||
.adjoin_assign(&flow_children.collapsible_margins_in_children.end);
|
||||
} else {
|
||||
flow_children.block_size += flow_children.collapsible_margins_in_children.end.solve();
|
||||
}
|
||||
block_margins_collapsed_with_children.collapsed_through =
|
||||
this_start_margin_can_collapse_with_children.0
|
||||
&& this_end_margin_can_collapse_with_children
|
||||
&& flow_children
|
||||
.collapsible_margins_in_children
|
||||
.collapsed_through;
|
||||
let relative_adjustement = relative_adjustement(style, inline_size, block_size);
|
||||
let block_size = block_size.auto_is(|| flow_children.block_size);
|
||||
let content_rect = Rect {
|
||||
start_corner: Vec2 {
|
||||
block: pb.block_start + relative_adjustement.block,
|
||||
inline: pb.inline_start + relative_adjustement.inline + margin.inline_start,
|
||||
},
|
||||
size: Vec2 {
|
||||
block: block_size,
|
||||
inline: inline_size,
|
||||
},
|
||||
};
|
||||
if style.box_.position.is_relatively_positioned() {
|
||||
AbsolutelyPositionedFragment::in_positioned_containing_block(
|
||||
&nested_abspos,
|
||||
&mut flow_children.fragments,
|
||||
&content_rect.size,
|
||||
&padding,
|
||||
containing_block_for_children.mode,
|
||||
)
|
||||
}
|
||||
BoxFragment {
|
||||
style: style.clone(),
|
||||
children: flow_children.fragments,
|
||||
content_rect,
|
||||
padding,
|
||||
border,
|
||||
margin,
|
||||
block_margins_collapsed_with_children,
|
||||
}
|
||||
}
|
||||
122
components/layout_2020/flow/root.rs
Normal file
122
components/layout_2020/flow/root.rs
Normal file
|
|
@ -0,0 +1,122 @@
|
|||
use super::*;
|
||||
|
||||
impl crate::dom::Document {
|
||||
pub(crate) fn layout(
|
||||
&self,
|
||||
viewport: crate::primitives::Size<crate::primitives::CssPx>,
|
||||
) -> Vec<Fragment> {
|
||||
BoxTreeRoot::construct(self).layout(viewport)
|
||||
}
|
||||
}
|
||||
|
||||
struct BoxTreeRoot(BlockFormattingContext);
|
||||
|
||||
impl BoxTreeRoot {
|
||||
pub fn construct(document: &dom::Document) -> Self {
|
||||
let author_styles = &document.parse_stylesheets();
|
||||
let context = Context {
|
||||
document,
|
||||
author_styles,
|
||||
};
|
||||
let root_element = document.root_element();
|
||||
let style = style_for_element(context.author_styles, context.document, root_element, None);
|
||||
let (contains_floats, boxes) = construct_for_root_element(&context, root_element, style);
|
||||
Self(BlockFormattingContext {
|
||||
contains_floats: contains_floats == ContainsFloats::Yes,
|
||||
contents: BlockContainer::BlockLevelBoxes(boxes),
|
||||
})
|
||||
}
|
||||
}
|
||||
|
||||
fn construct_for_root_element(
|
||||
context: &Context,
|
||||
root_element: dom::NodeId,
|
||||
style: Arc<ComputedValues>,
|
||||
) -> (ContainsFloats, Vec<Arc<BlockLevelBox>>) {
|
||||
let replaced = ReplacedContent::for_element(root_element, context);
|
||||
|
||||
let display_inside = match style.box_.display {
|
||||
Display::None => return (ContainsFloats::No, Vec::new()),
|
||||
Display::Contents if replaced.is_some() => {
|
||||
// 'display: contents' computes to 'none' for replaced elements
|
||||
return (ContainsFloats::No, Vec::new());
|
||||
}
|
||||
// https://drafts.csswg.org/css-display-3/#transformations
|
||||
Display::Contents => DisplayInside::Flow,
|
||||
// The root element is blockified, ignore DisplayOutside
|
||||
Display::GeneratingBox(DisplayGeneratingBox::OutsideInside { inside, .. }) => inside,
|
||||
};
|
||||
|
||||
if let Some(replaced) = replaced {
|
||||
let _box = match replaced {};
|
||||
#[allow(unreachable_code)]
|
||||
{
|
||||
return (ContainsFloats::No, vec![Arc::new(_box)]);
|
||||
}
|
||||
}
|
||||
|
||||
let contents = IndependentFormattingContext::construct(
|
||||
context,
|
||||
&style,
|
||||
display_inside,
|
||||
Contents::OfElement(root_element),
|
||||
);
|
||||
if style.box_.position.is_absolutely_positioned() {
|
||||
(
|
||||
ContainsFloats::No,
|
||||
vec![Arc::new(BlockLevelBox::OutOfFlowAbsolutelyPositionedBox(
|
||||
AbsolutelyPositionedBox { style, contents },
|
||||
))],
|
||||
)
|
||||
} else if style.box_.float.is_floating() {
|
||||
(
|
||||
ContainsFloats::Yes,
|
||||
vec![Arc::new(BlockLevelBox::OutOfFlowFloatBox(FloatBox {
|
||||
contents,
|
||||
style,
|
||||
}))],
|
||||
)
|
||||
} else {
|
||||
(
|
||||
ContainsFloats::No,
|
||||
vec![Arc::new(BlockLevelBox::Independent { style, contents })],
|
||||
)
|
||||
}
|
||||
}
|
||||
|
||||
impl BoxTreeRoot {
|
||||
fn layout(&self, viewport: crate::primitives::Size<crate::primitives::CssPx>) -> Vec<Fragment> {
|
||||
let initial_containing_block_size = Vec2 {
|
||||
inline: Length { px: viewport.width },
|
||||
block: Length {
|
||||
px: viewport.height,
|
||||
},
|
||||
};
|
||||
|
||||
let initial_containing_block = ContainingBlock {
|
||||
inline_size: initial_containing_block_size.inline,
|
||||
block_size: LengthOrAuto::Length(initial_containing_block_size.block),
|
||||
// FIXME: use the document’s mode:
|
||||
// https://drafts.csswg.org/css-writing-modes/#principal-flow
|
||||
mode: (WritingMode::HorizontalTb, Direction::Ltr),
|
||||
};
|
||||
let dummy_tree_rank = 0;
|
||||
let mut absolutely_positioned_fragments = vec![];
|
||||
let mut flow_children = self.0.layout(
|
||||
&initial_containing_block,
|
||||
dummy_tree_rank,
|
||||
&mut absolutely_positioned_fragments,
|
||||
);
|
||||
|
||||
let initial_containing_block = DefiniteContainingBlock {
|
||||
size: initial_containing_block_size,
|
||||
mode: initial_containing_block.mode,
|
||||
};
|
||||
flow_children.fragments.par_extend(
|
||||
absolutely_positioned_fragments
|
||||
.par_iter()
|
||||
.map(|a| a.layout(&initial_containing_block)),
|
||||
);
|
||||
flow_children.fragments
|
||||
}
|
||||
}
|
||||
Loading…
Add table
Add a link
Reference in a new issue