layout: Implement ordered lists, CSS counters, and quotes per CSS 2.1

§ 12.3-12.5.

Only simple alphabetic and numeric counter styles are supported. (This
is most of them though.)

Although this PR adds a sequential pass to layout, I verified that on
pages that contain a reasonable number of ordered lists (Reddit
`/r/rust`), the time spent in generated content resolution is dwarfed by
the time spent in the parallelizable parts of layout. So I don't expect
this to negatively affect our parallelism expect perhaps in pathological
cases.
This commit is contained in:
Patrick Walton 2015-03-05 12:37:37 -08:00
parent 2df4dd9e09
commit f9cdd05d58
39 changed files with 1704 additions and 537 deletions

View file

@ -33,9 +33,9 @@ use floats::Floats;
use flow_list::{FlowList, FlowListIterator, MutFlowListIterator};
use flow_ref::FlowRef;
use fragment::{Fragment, FragmentBorderBoxIterator, SpecificFragmentInfo};
use incremental::{RECONSTRUCT_FLOW, REFLOW, REFLOW_OUT_OF_FLOW, RestyleDamage};
use incremental::{self, RECONSTRUCT_FLOW, REFLOW, REFLOW_OUT_OF_FLOW, RestyleDamage};
use inline::InlineFlow;
use model::{CollapsibleMargins, IntrinsicISizes};
use model::{CollapsibleMargins, IntrinsicISizes, MarginCollapseInfo};
use parallel::FlowParallelInfo;
use table::{ColumnComputedInlineSize, ColumnIntrinsicInlineSize, TableFlow};
use table_caption::TableCaptionFlow;
@ -236,6 +236,15 @@ pub trait Flow: fmt::Debug + Sync {
iterator: &mut FragmentBorderBoxIterator,
stacking_context_position: &Point2D<Au>);
/// Mutably iterates through fragments in this flow.
fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment));
fn compute_collapsible_block_start_margin(&mut self,
_layout_context: &mut LayoutContext,
_margin_collapse_info: &mut MarginCollapseInfo) {
// The default implementation is a no-op.
}
/// Marks this flow as the root flow. The default implementation is a no-op.
fn mark_as_root(&mut self) {}
@ -478,51 +487,67 @@ pub trait PostorderFlowTraversal {
}
}
/// An in-order (sequential only) traversal.
pub trait InorderFlowTraversal {
/// The operation to perform. Returns the level of the tree we're at.
fn process(&mut self, flow: &mut Flow, level: u32);
/// Returns true if this node should be processed and false if neither this node nor its
/// descendants should be processed.
fn should_process(&mut self, flow: &mut Flow) -> bool;
}
bitflags! {
#[doc = "Flags used in flows."]
flags FlowFlags: u16 {
flags FlowFlags: u32 {
// floated descendants flags
#[doc = "Whether this flow has descendants that float left in the same block formatting"]
#[doc = "context."]
const HAS_LEFT_FLOATED_DESCENDANTS = 0b0000_0000_0000_0001,
const HAS_LEFT_FLOATED_DESCENDANTS = 0b0000_0000_0000_0000_0001,
#[doc = "Whether this flow has descendants that float right in the same block formatting"]
#[doc = "context."]
const HAS_RIGHT_FLOATED_DESCENDANTS = 0b0000_0000_0000_0010,
const HAS_RIGHT_FLOATED_DESCENDANTS = 0b0000_0000_0000_0000_0010,
#[doc = "Whether this flow is impacted by floats to the left in the same block formatting"]
#[doc = "context (i.e. its height depends on some prior flows with `float: left`)."]
const IMPACTED_BY_LEFT_FLOATS = 0b0000_0000_0000_0100,
const IMPACTED_BY_LEFT_FLOATS = 0b0000_0000_0000_0000_0100,
#[doc = "Whether this flow is impacted by floats to the right in the same block"]
#[doc = "formatting context (i.e. its height depends on some prior flows with `float:"]
#[doc = "right`)."]
const IMPACTED_BY_RIGHT_FLOATS = 0b0000_0000_0000_1000,
const IMPACTED_BY_RIGHT_FLOATS = 0b0000_0000_0000_0000_1000,
// text align flags
#[doc = "Whether this flow contains a flow that has its own layer within the same absolute"]
#[doc = "containing block."]
const LAYERS_NEEDED_FOR_DESCENDANTS = 0b0000_0000_0001_0000,
const LAYERS_NEEDED_FOR_DESCENDANTS = 0b0000_0000_0000_0001_0000,
#[doc = "Whether this flow must have its own layer. Even if this flag is not set, it might"]
#[doc = "get its own layer if it's deemed to be likely to overlap flows with their own"]
#[doc = "layer."]
const NEEDS_LAYER = 0b0000_0000_0010_0000,
const NEEDS_LAYER = 0b0000_0000_0000_0010_0000,
#[doc = "Whether this flow is absolutely positioned. This is checked all over layout, so a"]
#[doc = "virtual call is too expensive."]
const IS_ABSOLUTELY_POSITIONED = 0b0000_0000_0100_0000,
const IS_ABSOLUTELY_POSITIONED = 0b0000_0000_0000_0100_0000,
#[doc = "Whether this flow clears to the left. This is checked all over layout, so a"]
#[doc = "virtual call is too expensive."]
const CLEARS_LEFT = 0b0000_0000_1000_0000,
const CLEARS_LEFT = 0b0000_0000_0000_1000_0000,
#[doc = "Whether this flow clears to the right. This is checked all over layout, so a"]
#[doc = "virtual call is too expensive."]
const CLEARS_RIGHT = 0b0000_0001_0000_0000,
const CLEARS_RIGHT = 0b0000_0000_0001_0000_0000,
#[doc = "Whether this flow is left-floated. This is checked all over layout, so a"]
#[doc = "virtual call is too expensive."]
const FLOATS_LEFT = 0b0000_0010_0000_0000,
const FLOATS_LEFT = 0b0000_0000_0010_0000_0000,
#[doc = "Whether this flow is right-floated. This is checked all over layout, so a"]
#[doc = "virtual call is too expensive."]
const FLOATS_RIGHT = 0b0000_0100_0000_0000,
const FLOATS_RIGHT = 0b0000_0000_0100_0000_0000,
#[doc = "Text alignment. \
NB: If you update this, update `TEXT_ALIGN_SHIFT` below."]
const TEXT_ALIGN = 0b0111_1000_0000_0000,
const TEXT_ALIGN = 0b0000_0111_1000_0000_0000,
#[doc = "Whether this flow has a fragment with `counter-reset` or `counter-increment` \
styles."]
const AFFECTS_COUNTERS = 0b0000_1000_0000_0000_0000,
#[doc = "Whether this flow's descendants have fragments that affect `counter-reset` or \
`counter-increment` styles."]
const HAS_COUNTER_AFFECTING_CHILDREN = 0b0001_0000_0000_0000_0000
}
}
@ -548,13 +573,13 @@ impl FlowFlags {
#[inline]
pub fn text_align(self) -> text_align::T {
FromPrimitive::from_u16((self & TEXT_ALIGN).bits() >> TEXT_ALIGN_SHIFT).unwrap()
FromPrimitive::from_u32((self & TEXT_ALIGN).bits() >> TEXT_ALIGN_SHIFT).unwrap()
}
#[inline]
pub fn set_text_align(&mut self, value: text_align::T) {
*self = (*self & !TEXT_ALIGN) |
FlowFlags::from_bits((value as u16) << TEXT_ALIGN_SHIFT).unwrap();
FlowFlags::from_bits((value as u32) << TEXT_ALIGN_SHIFT).unwrap();
}
#[inline]
@ -885,39 +910,41 @@ impl BaseFlow {
force_nonfloated: ForceNonfloatedFlag)
-> BaseFlow {
let mut flags = FlowFlags::empty();
match node {
None => {}
Some(node) => {
let node_style = node.style();
match node_style.get_box().position {
position::T::absolute | position::T::fixed => {
flags.insert(IS_ABSOLUTELY_POSITIONED)
}
_ => {}
if let Some(node) = node {
let node_style = node.style();
match node_style.get_box().position {
position::T::absolute | position::T::fixed => {
flags.insert(IS_ABSOLUTELY_POSITIONED)
}
_ => {}
}
if force_nonfloated == ForceNonfloatedFlag::FloatIfNecessary {
match node_style.get_box().float {
float::T::none => {}
float::T::left => flags.insert(FLOATS_LEFT),
float::T::right => flags.insert(FLOATS_RIGHT),
}
if force_nonfloated == ForceNonfloatedFlag::FloatIfNecessary {
match node_style.get_box().float {
float::T::none => {}
float::T::left => flags.insert(FLOATS_LEFT),
float::T::right => flags.insert(FLOATS_RIGHT),
}
}
match node_style.get_box().clear {
clear::T::none => {}
clear::T::left => flags.insert(CLEARS_LEFT),
clear::T::right => flags.insert(CLEARS_RIGHT),
clear::T::both => {
flags.insert(CLEARS_LEFT);
flags.insert(CLEARS_RIGHT);
}
match node_style.get_box().clear {
clear::T::none => {}
clear::T::left => flags.insert(CLEARS_LEFT),
clear::T::right => flags.insert(CLEARS_RIGHT),
clear::T::both => {
flags.insert(CLEARS_LEFT);
flags.insert(CLEARS_RIGHT);
}
}
if !node_style.get_counters().counter_reset.0.is_empty() ||
!node_style.get_counters().counter_increment.0.is_empty() {
flags.insert(AFFECTS_COUNTERS)
}
}
// New flows start out as fully damaged.
let mut damage = RestyleDamage::all();
let mut damage = incremental::rebuild_and_reflow();
damage.remove(RECONSTRUCT_FLOW);
BaseFlow {
@ -992,10 +1019,12 @@ impl BaseFlow {
}
impl<'a> ImmutableFlowUtils for &'a (Flow + 'a) {
/// Returns true if this flow is a block flow.
/// Returns true if this flow is a block flow or subclass thereof.
fn is_block_like(self) -> bool {
match self.class() {
FlowClass::Block => true,
FlowClass::Block | FlowClass::ListItem | FlowClass::Table | FlowClass::TableRowGroup |
FlowClass::TableRow | FlowClass::TableCaption | FlowClass::TableCell |
FlowClass::TableWrapper => true,
_ => false,
}
}