mirror of
https://github.com/servo/servo.git
synced 2025-06-08 08:33:26 +00:00
98624c9576
This still needs a lot of work, but it covers the basic cases and improves wikipedia while passing all existing tests. Tweak reftest to deal with linux/travis black background.
1194 lines
52 KiB
Rust
1194 lines
52 KiB
Rust
/* This Source Code Form is subject to the terms of the Mozilla Public
|
|
* License, v. 2.0. If a copy of the MPL was not distributed with this
|
|
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
|
|
|
|
#![deny(unsafe_block)]
|
|
|
|
use css::node_style::StyledNode;
|
|
use context::LayoutContext;
|
|
use floats::{FloatLeft, Floats, PlacementInfo};
|
|
use flow::{BaseFlow, FlowClass, Flow, InlineFlowClass};
|
|
use flow;
|
|
use layout_debug;
|
|
use fragment::{Fragment, InlineBlockFragment, ScannedTextFragment, ScannedTextFragmentInfo, SplitInfo};
|
|
use model::IntrinsicISizes;
|
|
use text;
|
|
use wrapper::ThreadSafeLayoutNode;
|
|
|
|
use collections::{Deque, RingBuf};
|
|
use geom::Rect;
|
|
use gfx::display_list::ContentLevel;
|
|
use gfx::font::FontMetrics;
|
|
use gfx::font_context::FontContext;
|
|
use geom::Size2D;
|
|
use gfx::text::glyph::CharIndex;
|
|
use servo_util::geometry::Au;
|
|
use servo_util::geometry;
|
|
use servo_util::logical_geometry::{LogicalRect, LogicalSize};
|
|
use servo_util::range;
|
|
use servo_util::range::{EachIndex, Range, RangeIndex, IntRangeIndex};
|
|
use std::fmt;
|
|
use std::mem;
|
|
use std::num;
|
|
use std::u16;
|
|
use style::computed_values::{text_align, vertical_align, white_space};
|
|
use style::ComputedValues;
|
|
use sync::Arc;
|
|
|
|
/// `Line`s are represented as offsets into the child list, rather than
|
|
/// as an object that "owns" fragments. Choosing a different set of line
|
|
/// breaks requires a new list of offsets, and possibly some splitting and
|
|
/// merging of TextFragments.
|
|
///
|
|
/// A similar list will keep track of the mapping between CSS fragments and
|
|
/// the corresponding fragments in the inline flow.
|
|
///
|
|
/// After line breaks are determined, render fragments in the inline flow may
|
|
/// overlap visually. For example, in the case of nested inline CSS fragments,
|
|
/// outer inlines must be at least as large as the inner inlines, for
|
|
/// purposes of drawing noninherited things like backgrounds, borders,
|
|
/// outlines.
|
|
///
|
|
/// N.B. roc has an alternative design where the list instead consists of
|
|
/// things like "start outer fragment, text, start inner fragment, text, end inner
|
|
/// fragment, text, end outer fragment, text". This seems a little complicated to
|
|
/// serve as the starting point, but the current design doesn't make it
|
|
/// hard to try out that alternative.
|
|
///
|
|
/// Line fragments also contain some metadata used during line breaking. The
|
|
/// green zone is the area that the line can expand to before it collides
|
|
/// with a float or a horizontal wall of the containing block. The block-start
|
|
/// inline-start corner of the green zone is the same as that of the line, but
|
|
/// the green zone can be taller and wider than the line itself.
|
|
#[deriving(Encodable)]
|
|
pub struct Line {
|
|
/// A range of line indices that describe line breaks.
|
|
///
|
|
/// For example, consider the following HTML and rendered element with
|
|
/// linebreaks:
|
|
///
|
|
/// ~~~html
|
|
/// <span>I <span>like truffles, <img></span> yes I do.</span>
|
|
/// ~~~
|
|
///
|
|
/// ~~~text
|
|
/// +------------+
|
|
/// | I like |
|
|
/// | truffles, |
|
|
/// | +----+ |
|
|
/// | | | |
|
|
/// | +----+ yes |
|
|
/// | I do. |
|
|
/// +------------+
|
|
/// ~~~
|
|
///
|
|
/// The ranges that describe these lines would be:
|
|
///
|
|
/// | [0.0, 1.4) | [1.5, 2.0) | [2.0, 3.4) | [3.4, 4.0) |
|
|
/// |------------|-------------|-------------|------------|
|
|
/// | 'I like' | 'truffles,' | '<img> yes' | 'I do.' |
|
|
pub range: Range<LineIndices>,
|
|
/// The bounds are the exact position and extents of the line with respect
|
|
/// to the parent box.
|
|
///
|
|
/// For example, for the HTML below...
|
|
///
|
|
/// ~~~html
|
|
/// <div><span>I <span>like truffles, <img></span></div>
|
|
/// ~~~
|
|
///
|
|
/// ...the bounds would be:
|
|
///
|
|
/// ~~~text
|
|
/// +-----------------------------------------------------------+
|
|
/// | ^ |
|
|
/// | | |
|
|
/// | origin.y |
|
|
/// | | |
|
|
/// | v |
|
|
/// |< - origin.x ->+ - - - - - - - - +---------+---- |
|
|
/// | | | | ^ |
|
|
/// | | | <img> | size.block-size |
|
|
/// | I like truffles, | | v |
|
|
/// | + - - - - - - - - +---------+---- |
|
|
/// | | | |
|
|
/// | |<------ size.inline-size ------->| |
|
|
/// | |
|
|
/// | |
|
|
/// +-----------------------------------------------------------+
|
|
/// ~~~
|
|
pub bounds: LogicalRect<Au>,
|
|
/// The green zone is the greatest extent from wich a line can extend to
|
|
/// before it collides with a float.
|
|
///
|
|
/// ~~~text
|
|
/// +-----------------------+
|
|
/// |::::::::::::::::: |
|
|
/// |:::::::::::::::::FFFFFF|
|
|
/// |============:::::FFFFFF|
|
|
/// |:::::::::::::::::FFFFFF|
|
|
/// |:::::::::::::::::FFFFFF|
|
|
/// |::::::::::::::::: |
|
|
/// | FFFFFFFFF |
|
|
/// | FFFFFFFFF |
|
|
/// | FFFFFFFFF |
|
|
/// | |
|
|
/// +-----------------------+
|
|
///
|
|
/// === line
|
|
/// ::: green zone
|
|
/// FFF float
|
|
/// ~~~
|
|
pub green_zone: LogicalSize<Au>
|
|
}
|
|
|
|
int_range_index! {
|
|
#[deriving(Encodable)]
|
|
#[doc = "The index of a fragment in a flattened vector of DOM elements."]
|
|
struct FragmentIndex(int)
|
|
}
|
|
|
|
/// A line index consists of two indices: a fragment index that refers to the
|
|
/// index of a DOM fragment within a flattened inline element; and a glyph index
|
|
/// where the 0th glyph refers to the first glyph of that fragment.
|
|
#[deriving(Clone, Encodable, PartialEq, PartialOrd, Eq, Ord, Zero)]
|
|
pub struct LineIndices {
|
|
/// The index of a fragment into the flattened vector of DOM elements.
|
|
///
|
|
/// For example, given the HTML below:
|
|
///
|
|
/// ~~~html
|
|
/// <span>I <span>like truffles, <img></span> yes I do.</span>
|
|
/// ~~~
|
|
///
|
|
/// The fragments would be indexed as follows:
|
|
///
|
|
/// | 0 | 1 | 2 | 3 |
|
|
/// |------|------------------|---------|--------------|
|
|
/// | 'I ' | 'like truffles,' | `<img>` | ' yes I do.' |
|
|
pub fragment_index: FragmentIndex,
|
|
/// The index of a character in a DOM fragment. Continuous runs of whitespace
|
|
/// are treated as single characters. Non-breakable DOM fragments such as
|
|
/// images are treated as having a range length of `1`.
|
|
///
|
|
/// For example, given the HTML below:
|
|
///
|
|
/// ~~~html
|
|
/// <span>I <span>like truffles, <img></span> yes I do.</span>
|
|
/// ~~~
|
|
///
|
|
/// The characters would be indexed as follows:
|
|
///
|
|
/// | 0 | 1 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 |
|
|
/// |---|---|---|---|---|---|---|---|---|---|---|---|----|----|----|----|----|
|
|
/// | I | | l | i | k | e | | t | r | u | f | f | l | e | s | , | |
|
|
///
|
|
/// | 0 | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
|
|
/// |---------|---|---|---|---|---|---|---|---|---|---|
|
|
/// | `<img>` | | y | e | s | | I | | d | o | . |
|
|
pub char_index: CharIndex,
|
|
}
|
|
|
|
impl RangeIndex for LineIndices {}
|
|
|
|
impl Add<LineIndices, LineIndices> for LineIndices {
|
|
fn add(&self, other: &LineIndices) -> LineIndices {
|
|
// TODO: use debug_assert! after rustc upgrade
|
|
if cfg!(not(ndebug)) {
|
|
assert!(other.fragment_index == num::zero() || other.char_index == num::zero(),
|
|
"Attempted to add {} to {}. Both the fragment_index and \
|
|
char_index of the RHS are non-zero. This probably was a \
|
|
mistake!", self, other);
|
|
}
|
|
LineIndices {
|
|
fragment_index: self.fragment_index + other.fragment_index,
|
|
char_index: self.char_index + other.char_index,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl Sub<LineIndices, LineIndices> for LineIndices {
|
|
fn sub(&self, other: &LineIndices) -> LineIndices {
|
|
// TODO: use debug_assert! after rustc upgrade
|
|
if cfg!(not(ndebug)) {
|
|
assert!(other.fragment_index == num::zero() || other.char_index == num::zero(),
|
|
"Attempted to subtract {} from {}. Both the fragment_index \
|
|
and char_index of the RHS are non-zero. This probably was \
|
|
a mistake!", self, other);
|
|
}
|
|
LineIndices {
|
|
fragment_index: self.fragment_index - other.fragment_index,
|
|
char_index: self.char_index - other.char_index,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl Neg<LineIndices> for LineIndices {
|
|
fn neg(&self) -> LineIndices {
|
|
// TODO: use debug_assert! after rustc upgrade
|
|
if cfg!(not(ndebug)) {
|
|
assert!(self.fragment_index == num::zero() || self.char_index == num::zero(),
|
|
"Attempted to negate {}. Both the fragment_index and \
|
|
char_index are non-zero. This probably was a mistake!",
|
|
self);
|
|
}
|
|
LineIndices {
|
|
fragment_index: -self.fragment_index,
|
|
char_index: -self.char_index,
|
|
}
|
|
}
|
|
}
|
|
|
|
impl fmt::Show for LineIndices {
|
|
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
|
|
write!(f, "{}.{}", self.fragment_index, self.char_index)
|
|
}
|
|
}
|
|
|
|
pub fn each_fragment_index(range: &Range<LineIndices>) -> EachIndex<int, FragmentIndex> {
|
|
range::each_index(range.begin().fragment_index, range.end().fragment_index)
|
|
}
|
|
|
|
pub fn each_char_index(range: &Range<LineIndices>) -> EachIndex<int, CharIndex> {
|
|
range::each_index(range.begin().char_index, range.end().char_index)
|
|
}
|
|
|
|
struct LineBreaker {
|
|
pub floats: Floats,
|
|
pub new_fragments: Vec<Fragment>,
|
|
pub work_list: RingBuf<Fragment>,
|
|
pub pending_line: Line,
|
|
pub lines: Vec<Line>,
|
|
pub cur_b: Au, // Current position on the block direction
|
|
}
|
|
|
|
impl LineBreaker {
|
|
pub fn new(float_ctx: Floats) -> LineBreaker {
|
|
LineBreaker {
|
|
new_fragments: Vec::new(),
|
|
work_list: RingBuf::new(),
|
|
pending_line: Line {
|
|
range: Range::empty(),
|
|
bounds: LogicalRect::zero(float_ctx.writing_mode),
|
|
green_zone: LogicalSize::zero(float_ctx.writing_mode)
|
|
},
|
|
floats: float_ctx,
|
|
lines: Vec::new(),
|
|
cur_b: Au::new(0)
|
|
}
|
|
}
|
|
|
|
pub fn floats(&mut self) -> Floats {
|
|
self.floats.clone()
|
|
}
|
|
|
|
fn reset_scanner(&mut self) {
|
|
debug!("Resetting LineBreaker's state for flow.");
|
|
self.lines = Vec::new();
|
|
self.new_fragments = Vec::new();
|
|
self.cur_b = Au(0);
|
|
self.reset_line();
|
|
}
|
|
|
|
fn reset_line(&mut self) {
|
|
self.pending_line.range.reset(num::zero(), num::zero());
|
|
self.pending_line.bounds = LogicalRect::new(
|
|
self.floats.writing_mode, Au::new(0), self.cur_b, Au::new(0), Au::new(0));
|
|
self.pending_line.green_zone = LogicalSize::zero(self.floats.writing_mode)
|
|
}
|
|
|
|
pub fn scan_for_lines(&mut self, flow: &mut InlineFlow, layout_context: &LayoutContext) {
|
|
self.reset_scanner();
|
|
|
|
let mut old_fragments = mem::replace(&mut flow.fragments, InlineFragments::new());
|
|
|
|
{ // Enter a new scope so that old_fragment_iter's borrow is released
|
|
let mut old_fragment_iter = old_fragments.fragments.iter();
|
|
loop {
|
|
// acquire the next fragment to lay out from work list or fragment list
|
|
let cur_fragment = if self.work_list.is_empty() {
|
|
match old_fragment_iter.next() {
|
|
None => break,
|
|
Some(fragment) => {
|
|
debug!("LineBreaker: Working with fragment from flow: b{}",
|
|
fragment.debug_id());
|
|
(*fragment).clone()
|
|
}
|
|
}
|
|
} else {
|
|
let fragment = self.work_list.pop_front().unwrap();
|
|
debug!("LineBreaker: Working with fragment from work list: b{}",
|
|
fragment.debug_id());
|
|
fragment
|
|
};
|
|
|
|
let fragment_was_appended = match cur_fragment.white_space() {
|
|
white_space::normal => self.try_append_to_line(cur_fragment, flow, layout_context),
|
|
white_space::pre => self.try_append_to_line_by_new_line(cur_fragment),
|
|
};
|
|
|
|
if !fragment_was_appended {
|
|
debug!("LineBreaker: Fragment wasn't appended, because line {:u} was full.",
|
|
self.lines.len());
|
|
self.flush_current_line();
|
|
} else {
|
|
debug!("LineBreaker: appended a fragment to line {:u}", self.lines.len());
|
|
}
|
|
}
|
|
|
|
if self.pending_line.range.length() > num::zero() {
|
|
debug!("LineBreaker: Partially full line {:u} inline_start at end of scanning.",
|
|
self.lines.len());
|
|
self.flush_current_line();
|
|
}
|
|
}
|
|
|
|
old_fragments.fragments = mem::replace(&mut self.new_fragments, vec![]);
|
|
flow.fragments = old_fragments;
|
|
flow.lines = mem::replace(&mut self.lines, Vec::new());
|
|
}
|
|
|
|
fn flush_current_line(&mut self) {
|
|
debug!("LineBreaker: Flushing line {:u}: {:?}",
|
|
self.lines.len(), self.pending_line);
|
|
|
|
// clear line and add line mapping
|
|
debug!("LineBreaker: Saving information for flushed line {:u}.", self.lines.len());
|
|
self.lines.push(self.pending_line);
|
|
self.cur_b = self.pending_line.bounds.start.b + self.pending_line.bounds.size.block;
|
|
self.reset_line();
|
|
}
|
|
|
|
// FIXME(eatkinson): this assumes that the tallest fragment in the line determines the line block-size
|
|
// This might not be the case with some weird text fonts.
|
|
fn new_block_size_for_line(&self, new_fragment: &Fragment, layout_context: &LayoutContext) -> Au {
|
|
let fragment_block_size = new_fragment.content_block_size(layout_context);
|
|
if fragment_block_size > self.pending_line.bounds.size.block {
|
|
fragment_block_size
|
|
} else {
|
|
self.pending_line.bounds.size.block
|
|
}
|
|
}
|
|
|
|
/// Computes the position of a line that has only the provided fragment. Returns the bounding
|
|
/// rect of the line's green zone (whose origin coincides with the line's origin) and the actual
|
|
/// inline-size of the first fragment after splitting.
|
|
fn initial_line_placement(&self, first_fragment: &Fragment, ceiling: Au, flow: &InlineFlow)
|
|
-> (LogicalRect<Au>, Au) {
|
|
debug!("LineBreaker: Trying to place first fragment of line {}", self.lines.len());
|
|
|
|
let first_fragment_size = first_fragment.border_box.size;
|
|
let splittable = first_fragment.can_split();
|
|
debug!("LineBreaker: fragment size: {}, splittable: {}", first_fragment_size, splittable);
|
|
|
|
// Initally, pretend a splittable fragment has 0 inline-size.
|
|
// We will move it later if it has nonzero inline-size
|
|
// and that causes problems.
|
|
let placement_inline_size = if splittable {
|
|
Au::new(0)
|
|
} else {
|
|
first_fragment_size.inline
|
|
};
|
|
|
|
let info = PlacementInfo {
|
|
size: LogicalSize::new(
|
|
self.floats.writing_mode, placement_inline_size, first_fragment_size.block),
|
|
ceiling: ceiling,
|
|
max_inline_size: flow.base.position.size.inline,
|
|
kind: FloatLeft,
|
|
};
|
|
|
|
let line_bounds = self.floats.place_between_floats(&info);
|
|
|
|
debug!("LineBreaker: found position for line: {} using placement_info: {:?}",
|
|
line_bounds,
|
|
info);
|
|
|
|
// Simple case: if the fragment fits, then we can stop here
|
|
if line_bounds.size.inline > first_fragment_size.inline {
|
|
debug!("LineBreaker: case=fragment fits");
|
|
return (line_bounds, first_fragment_size.inline);
|
|
}
|
|
|
|
// If not, but we can't split the fragment, then we'll place
|
|
// the line here and it will overflow.
|
|
if !splittable {
|
|
debug!("LineBreaker: case=line doesn't fit, but is unsplittable");
|
|
return (line_bounds, first_fragment_size.inline);
|
|
}
|
|
|
|
debug!("LineBreaker: used to call split_to_inline_size here");
|
|
return (line_bounds, first_fragment_size.inline);
|
|
}
|
|
|
|
/// Performs float collision avoidance. This is called when adding a fragment is going to increase
|
|
/// the block-size, and because of that we will collide with some floats.
|
|
///
|
|
/// We have two options here:
|
|
/// 1) Move the entire line so that it doesn't collide any more.
|
|
/// 2) Break the line and put the new fragment on the next line.
|
|
///
|
|
/// The problem with option 1 is that we might move the line and then wind up breaking anyway,
|
|
/// which violates the standard.
|
|
/// But option 2 is going to look weird sometimes.
|
|
///
|
|
/// So we'll try to move the line whenever we can, but break if we have to.
|
|
///
|
|
/// Returns false if and only if we should break the line.
|
|
fn avoid_floats(&mut self,
|
|
in_fragment: Fragment,
|
|
flow: &InlineFlow,
|
|
new_block_size: Au,
|
|
line_is_empty: bool)
|
|
-> bool {
|
|
debug!("LineBreaker: entering float collision avoider!");
|
|
|
|
// First predict where the next line is going to be.
|
|
let this_line_y = self.pending_line.bounds.start.b;
|
|
let (next_line, first_fragment_inline_size) = self.initial_line_placement(&in_fragment, this_line_y, flow);
|
|
let next_green_zone = next_line.size;
|
|
|
|
let new_inline_size = self.pending_line.bounds.size.inline + first_fragment_inline_size;
|
|
|
|
// Now, see if everything can fit at the new location.
|
|
if next_green_zone.inline >= new_inline_size && next_green_zone.block >= new_block_size {
|
|
debug!("LineBreaker: case=adding fragment collides vertically with floats: moving line");
|
|
|
|
self.pending_line.bounds.start = next_line.start;
|
|
self.pending_line.green_zone = next_green_zone;
|
|
|
|
assert!(!line_is_empty, "Non-terminating line breaking");
|
|
self.work_list.push_front(in_fragment);
|
|
return true
|
|
}
|
|
|
|
debug!("LineBreaker: case=adding fragment collides vertically with floats: breaking line");
|
|
self.work_list.push_front(in_fragment);
|
|
false
|
|
}
|
|
|
|
fn try_append_to_line_by_new_line(&mut self, in_fragment: Fragment) -> bool {
|
|
if in_fragment.new_line_pos.len() == 0 {
|
|
debug!("LineBreaker: Did not find a new-line character, so pushing the fragment to \
|
|
the line without splitting.");
|
|
self.push_fragment_to_line(in_fragment);
|
|
true
|
|
} else {
|
|
debug!("LineBreaker: Found a new-line character, so splitting theline.");
|
|
|
|
let (inline_start, inline_end, run) = in_fragment.find_split_info_by_new_line()
|
|
.expect("LineBreaker: This split case makes no sense!");
|
|
let writing_mode = self.floats.writing_mode;
|
|
|
|
// TODO(bjz): Remove fragment splitting
|
|
let split_fragment = |split: SplitInfo| {
|
|
let info = ScannedTextFragmentInfo::new(run.clone(), split.range);
|
|
let specific = ScannedTextFragment(info);
|
|
let size = LogicalSize::new(
|
|
writing_mode, split.inline_size, in_fragment.border_box.size.block);
|
|
in_fragment.transform(size, specific)
|
|
};
|
|
|
|
debug!("LineBreaker: Pushing the fragment to the inline_start of the new-line character \
|
|
to the line.");
|
|
let mut inline_start = split_fragment(inline_start);
|
|
inline_start.new_line_pos = vec![];
|
|
self.push_fragment_to_line(inline_start);
|
|
|
|
for inline_end in inline_end.move_iter() {
|
|
debug!("LineBreaker: Deferring the fragment to the inline_end of the new-line \
|
|
character to the line.");
|
|
let mut inline_end = split_fragment(inline_end);
|
|
inline_end.new_line_pos = in_fragment.new_line_pos.clone();
|
|
self.work_list.push_front(inline_end);
|
|
}
|
|
false
|
|
}
|
|
}
|
|
|
|
/// Tries to append the given fragment to the line, splitting it if necessary. Returns false only if
|
|
/// we should break the line.
|
|
fn try_append_to_line(&mut self, in_fragment: Fragment, flow: &InlineFlow, layout_context: &LayoutContext) -> bool {
|
|
let line_is_empty = self.pending_line.range.length() == num::zero();
|
|
if line_is_empty {
|
|
let (line_bounds, _) = self.initial_line_placement(&in_fragment, self.cur_b, flow);
|
|
self.pending_line.bounds.start = line_bounds.start;
|
|
self.pending_line.green_zone = line_bounds.size;
|
|
}
|
|
|
|
debug!("LineBreaker: Trying to append fragment to line {:u} (fragment size: {}, green zone: \
|
|
{}): {}",
|
|
self.lines.len(),
|
|
in_fragment.border_box.size,
|
|
self.pending_line.green_zone,
|
|
in_fragment);
|
|
|
|
let green_zone = self.pending_line.green_zone;
|
|
|
|
// NB: At this point, if `green_zone.inline-size < self.pending_line.bounds.size.inline-size` or
|
|
// `green_zone.block-size < self.pending_line.bounds.size.block-size`, then we committed a line
|
|
// that overlaps with floats.
|
|
|
|
let new_block_size = self.new_block_size_for_line(&in_fragment, layout_context);
|
|
if new_block_size > green_zone.block {
|
|
// Uh-oh. Float collision imminent. Enter the float collision avoider
|
|
return self.avoid_floats(in_fragment, flow, new_block_size, line_is_empty)
|
|
}
|
|
|
|
// If we're not going to overflow the green zone vertically, we might still do so
|
|
// horizontally. We'll try to place the whole fragment on this line and break somewhere if it
|
|
// doesn't fit.
|
|
|
|
let new_inline_size = self.pending_line.bounds.size.inline + in_fragment.border_box.size.inline;
|
|
if new_inline_size <= green_zone.inline {
|
|
debug!("LineBreaker: case=fragment fits without splitting");
|
|
self.push_fragment_to_line(in_fragment);
|
|
return true
|
|
}
|
|
|
|
if !in_fragment.can_split() {
|
|
// TODO(eatkinson, issue #224): Signal that horizontal overflow happened?
|
|
if line_is_empty {
|
|
debug!("LineBreaker: case=fragment can't split and line {:u} is empty, so \
|
|
overflowing.",
|
|
self.lines.len());
|
|
self.push_fragment_to_line(in_fragment);
|
|
return true
|
|
}
|
|
}
|
|
|
|
let available_inline_size = green_zone.inline - self.pending_line.bounds.size.inline;
|
|
let split = in_fragment.find_split_info_for_inline_size(CharIndex(0), available_inline_size, line_is_empty);
|
|
match split.map(|(inline_start, inline_end, run)| {
|
|
// TODO(bjz): Remove fragment splitting
|
|
let split_fragment = |split: SplitInfo| {
|
|
let info = ScannedTextFragmentInfo::new(run.clone(), split.range);
|
|
let specific = ScannedTextFragment(info);
|
|
let size = LogicalSize::new(
|
|
self.floats.writing_mode, split.inline_size, in_fragment.border_box.size.block);
|
|
in_fragment.transform(size, specific)
|
|
};
|
|
|
|
(inline_start.map(|x| { debug!("LineBreaker: Left split {}", x); split_fragment(x) }),
|
|
inline_end.map(|x| { debug!("LineBreaker: Right split {}", x); split_fragment(x) }))
|
|
}) {
|
|
None => {
|
|
debug!("LineBreaker: Tried to split unsplittable render fragment! Deferring to next \
|
|
line. {}", in_fragment);
|
|
self.work_list.push_front(in_fragment);
|
|
false
|
|
},
|
|
Some((Some(inline_start_fragment), Some(inline_end_fragment))) => {
|
|
debug!("LineBreaker: Line break found! Pushing inline_start fragment to line and deferring \
|
|
inline_end fragment to next line.");
|
|
self.push_fragment_to_line(inline_start_fragment);
|
|
self.work_list.push_front(inline_end_fragment);
|
|
true
|
|
},
|
|
Some((Some(inline_start_fragment), None)) => {
|
|
debug!("LineBreaker: Pushing inline_start fragment to line.");
|
|
self.push_fragment_to_line(inline_start_fragment);
|
|
true
|
|
},
|
|
Some((None, Some(inline_end_fragment))) => {
|
|
debug!("LineBreaker: Pushing inline_end fragment to line.");
|
|
self.push_fragment_to_line(inline_end_fragment);
|
|
true
|
|
},
|
|
Some((None, None)) => {
|
|
error!("LineBreaker: This split case makes no sense!");
|
|
true
|
|
},
|
|
}
|
|
}
|
|
|
|
// An unconditional push
|
|
fn push_fragment_to_line(&mut self, fragment: Fragment) {
|
|
debug!("LineBreaker: Pushing fragment {} to line {:u}", fragment.debug_id(), self.lines.len());
|
|
|
|
if self.pending_line.range.length() == num::zero() {
|
|
assert!(self.new_fragments.len() <= (u16::MAX as uint));
|
|
self.pending_line.range.reset(
|
|
LineIndices {
|
|
fragment_index: FragmentIndex(self.new_fragments.len() as int),
|
|
char_index: CharIndex(0) /* unused for now */,
|
|
},
|
|
num::zero()
|
|
);
|
|
}
|
|
self.pending_line.range.extend_by(LineIndices {
|
|
fragment_index: FragmentIndex(1),
|
|
char_index: CharIndex(0) /* unused for now */ ,
|
|
});
|
|
self.pending_line.bounds.size.inline = self.pending_line.bounds.size.inline +
|
|
fragment.border_box.size.inline;
|
|
self.pending_line.bounds.size.block = Au::max(self.pending_line.bounds.size.block,
|
|
fragment.border_box.size.block);
|
|
self.new_fragments.push(fragment);
|
|
}
|
|
}
|
|
|
|
/// Represents a list of inline fragments, including element ranges.
|
|
#[deriving(Encodable)]
|
|
pub struct InlineFragments {
|
|
/// The fragments themselves.
|
|
pub fragments: Vec<Fragment>,
|
|
}
|
|
|
|
impl InlineFragments {
|
|
/// Creates an empty set of inline fragments.
|
|
pub fn new() -> InlineFragments {
|
|
InlineFragments {
|
|
fragments: vec![],
|
|
}
|
|
}
|
|
|
|
/// Returns the number of inline fragments.
|
|
pub fn len(&self) -> uint {
|
|
self.fragments.len()
|
|
}
|
|
|
|
/// Returns true if this list contains no fragments and false if it contains at least one fragment.
|
|
pub fn is_empty(&self) -> bool {
|
|
self.len() == 0
|
|
}
|
|
|
|
/// Pushes a new inline fragment.
|
|
pub fn push(&mut self, fragment: &mut Fragment, style: Arc<ComputedValues>) {
|
|
fragment.add_inline_context_style(style);
|
|
self.fragments.push(fragment.clone());
|
|
}
|
|
|
|
/// Merges another set of inline fragments with this one.
|
|
pub fn push_all(&mut self, fragments: InlineFragments) {
|
|
self.fragments.push_all_move(fragments.fragments);
|
|
}
|
|
|
|
/// A convenience function to return the fragment at a given index.
|
|
pub fn get<'a>(&'a self, index: uint) -> &'a Fragment {
|
|
&self.fragments[index]
|
|
}
|
|
|
|
/// A convenience function to return a mutable reference to the fragment at a given index.
|
|
pub fn get_mut<'a>(&'a mut self, index: uint) -> &'a mut Fragment {
|
|
self.fragments.get_mut(index)
|
|
}
|
|
|
|
/// Strips ignorable whitespace from the start of a list of fragments.
|
|
pub fn strip_ignorable_whitespace_from_start(&mut self) {
|
|
if self.is_empty() { return }; // Fast path
|
|
|
|
// FIXME (rust#16151): This can be reverted back to using skip_while once
|
|
// the upstream bug is fixed.
|
|
let mut fragments = mem::replace(&mut self.fragments, vec![]).move_iter();
|
|
let mut new_fragments = Vec::new();
|
|
let mut skipping = true;
|
|
for fragment in fragments {
|
|
if skipping && fragment.is_whitespace_only() {
|
|
debug!("stripping ignorable whitespace from start");
|
|
continue
|
|
}
|
|
|
|
skipping = false;
|
|
new_fragments.push(fragment);
|
|
}
|
|
|
|
self.fragments = new_fragments;
|
|
}
|
|
|
|
/// Strips ignorable whitespace from the end of a list of fragments.
|
|
pub fn strip_ignorable_whitespace_from_end(&mut self) {
|
|
if self.is_empty() {
|
|
return;
|
|
}
|
|
|
|
let mut new_fragments = self.fragments.clone();
|
|
while new_fragments.len() > 0 && new_fragments.as_slice().last().get_ref().is_whitespace_only() {
|
|
debug!("stripping ignorable whitespace from end");
|
|
drop(new_fragments.pop());
|
|
}
|
|
|
|
|
|
self.fragments = new_fragments;
|
|
}
|
|
}
|
|
|
|
/// Flows for inline layout.
|
|
#[deriving(Encodable)]
|
|
pub struct InlineFlow {
|
|
/// Data common to all flows.
|
|
pub base: BaseFlow,
|
|
|
|
/// A vector of all inline fragments. Several fragments may correspond to one node/element.
|
|
pub fragments: InlineFragments,
|
|
|
|
/// A vector of ranges into fragments that represents line positions. These ranges are disjoint and
|
|
/// are the result of inline layout. This also includes some metadata used for positioning
|
|
/// lines.
|
|
pub lines: Vec<Line>,
|
|
|
|
/// The minimum block-size above the baseline for each line, as specified by the line block-size and
|
|
/// font style.
|
|
pub minimum_block_size_above_baseline: Au,
|
|
|
|
/// The minimum depth below the baseline for each line, as specified by the line block-size and
|
|
/// font style.
|
|
pub minimum_depth_below_baseline: Au,
|
|
}
|
|
|
|
impl InlineFlow {
|
|
pub fn from_fragments(node: ThreadSafeLayoutNode, fragments: InlineFragments) -> InlineFlow {
|
|
InlineFlow {
|
|
base: BaseFlow::new(node),
|
|
fragments: fragments,
|
|
lines: Vec::new(),
|
|
minimum_block_size_above_baseline: Au(0),
|
|
minimum_depth_below_baseline: Au(0),
|
|
}
|
|
}
|
|
|
|
pub fn build_display_list_inline(&mut self, layout_context: &LayoutContext) {
|
|
let size = self.base.position.size.to_physical(self.base.writing_mode);
|
|
if !Rect(self.base.abs_position, size).intersects(&layout_context.shared.dirty) {
|
|
return
|
|
}
|
|
|
|
// TODO(#228): Once we form lines and have their cached bounds, we can be smarter and
|
|
// not recurse on a line if nothing in it can intersect the dirty region.
|
|
debug!("Flow: building display list for {:u} inline fragments", self.fragments.len());
|
|
|
|
for fragment in self.fragments.fragments.mut_iter() {
|
|
let rel_offset = fragment.relative_position(&self.base
|
|
.absolute_position_info
|
|
.relative_containing_block_size);
|
|
let mut accumulator = fragment.build_display_list(&mut self.base.display_list,
|
|
layout_context,
|
|
self.base.abs_position.add_size(
|
|
&rel_offset.to_physical(self.base.writing_mode)),
|
|
ContentLevel);
|
|
match fragment.specific {
|
|
InlineBlockFragment(ref mut block_flow) => {
|
|
let block_flow = block_flow.flow_ref.get_mut();
|
|
accumulator.push_child(&mut self.base.display_list, block_flow);
|
|
}
|
|
_ => {}
|
|
}
|
|
}
|
|
|
|
// TODO(#225): Should `inline-block` elements have flows as children of the inline flow or
|
|
// should the flow be nested inside the fragment somehow?
|
|
|
|
// For now, don't traverse the subtree rooted here.
|
|
}
|
|
|
|
/// Returns the distance from the baseline for the logical block-start inline-start corner of this fragment,
|
|
/// taking into account the value of the CSS `vertical-align` property. Negative values mean
|
|
/// "toward the logical block-start" and positive values mean "toward the logical block-end".
|
|
///
|
|
/// The extra boolean is set if and only if `biggest_block-start` and/or `biggest_block-end` were updated.
|
|
/// That is, if the box has a `block-start` or `block-end` value, true is returned.
|
|
fn distance_from_baseline(fragment: &Fragment,
|
|
ascent: Au,
|
|
parent_text_block_start: Au,
|
|
parent_text_block_end: Au,
|
|
block_size_above_baseline: &mut Au,
|
|
depth_below_baseline: &mut Au,
|
|
largest_block_size_for_top_fragments: &mut Au,
|
|
largest_block_size_for_bottom_fragments: &mut Au,
|
|
layout_context: &LayoutContext)
|
|
-> (Au, bool) {
|
|
match fragment.vertical_align() {
|
|
vertical_align::baseline => (-ascent, false),
|
|
vertical_align::middle => {
|
|
// TODO: x-block-size value should be used from font info.
|
|
let xblock_size = Au(0);
|
|
let fragment_block_size = fragment.content_block_size(layout_context);
|
|
let offset_block_start = -(xblock_size + fragment_block_size).scale_by(0.5);
|
|
*block_size_above_baseline = offset_block_start.scale_by(-1.0);
|
|
*depth_below_baseline = fragment_block_size - *block_size_above_baseline;
|
|
(offset_block_start, false)
|
|
},
|
|
vertical_align::sub => {
|
|
// TODO: The proper position for subscripts should be used. Lower the baseline to
|
|
// the proper position for subscripts.
|
|
let sub_offset = Au(0);
|
|
(sub_offset - ascent, false)
|
|
},
|
|
vertical_align::super_ => {
|
|
// TODO: The proper position for superscripts should be used. Raise the baseline to
|
|
// the proper position for superscripts.
|
|
let super_offset = Au(0);
|
|
(-super_offset - ascent, false)
|
|
},
|
|
vertical_align::text_top => {
|
|
let fragment_block_size = *block_size_above_baseline + *depth_below_baseline;
|
|
let prev_depth_below_baseline = *depth_below_baseline;
|
|
*block_size_above_baseline = parent_text_block_start;
|
|
*depth_below_baseline = fragment_block_size - *block_size_above_baseline;
|
|
(*depth_below_baseline - prev_depth_below_baseline - ascent, false)
|
|
},
|
|
vertical_align::text_bottom => {
|
|
let fragment_block_size = *block_size_above_baseline + *depth_below_baseline;
|
|
let prev_depth_below_baseline = *depth_below_baseline;
|
|
*depth_below_baseline = parent_text_block_end;
|
|
*block_size_above_baseline = fragment_block_size - *depth_below_baseline;
|
|
(*depth_below_baseline - prev_depth_below_baseline - ascent, false)
|
|
},
|
|
vertical_align::top => {
|
|
*largest_block_size_for_top_fragments =
|
|
Au::max(*largest_block_size_for_top_fragments,
|
|
*block_size_above_baseline + *depth_below_baseline);
|
|
let offset_top = *block_size_above_baseline - ascent;
|
|
(offset_top, true)
|
|
},
|
|
vertical_align::bottom => {
|
|
*largest_block_size_for_bottom_fragments =
|
|
Au::max(*largest_block_size_for_bottom_fragments,
|
|
*block_size_above_baseline + *depth_below_baseline);
|
|
let offset_bottom = -(*depth_below_baseline + ascent);
|
|
(offset_bottom, true)
|
|
},
|
|
vertical_align::Length(length) => (-(length + ascent), false),
|
|
vertical_align::Percentage(p) => {
|
|
let line_height = fragment.calculate_line_height(layout_context);
|
|
let percent_offset = line_height.scale_by(p);
|
|
(-(percent_offset + ascent), false)
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Sets fragment X positions based on alignment for one line.
|
|
fn set_horizontal_fragment_positions(fragments: &mut InlineFragments,
|
|
line: &Line,
|
|
line_align: text_align::T) {
|
|
// Figure out how much inline-size we have.
|
|
let slack_inline_size = Au::max(Au(0), line.green_zone.inline - line.bounds.size.inline);
|
|
|
|
// Set the fragment x positions based on that alignment.
|
|
let mut offset_x = line.bounds.start.i;
|
|
offset_x = offset_x + match line_align {
|
|
// So sorry, but justified text is more complicated than shuffling line
|
|
// coordinates.
|
|
//
|
|
// TODO(burg, issue #213): Implement `text-align: justify`.
|
|
text_align::left | text_align::justify => Au(0),
|
|
text_align::center => slack_inline_size.scale_by(0.5),
|
|
text_align::right => slack_inline_size,
|
|
};
|
|
|
|
for i in each_fragment_index(&line.range) {
|
|
let fragment = fragments.get_mut(i.to_uint());
|
|
let size = fragment.border_box.size;
|
|
fragment.border_box = LogicalRect::new(
|
|
fragment.style.writing_mode, offset_x, fragment.border_box.start.b,
|
|
size.inline, size.block);
|
|
offset_x = offset_x + size.inline;
|
|
}
|
|
}
|
|
|
|
/// Computes the minimum ascent and descent for each line. This is done during flow
|
|
/// construction.
|
|
///
|
|
/// `style` is the style of the block.
|
|
pub fn compute_minimum_ascent_and_descent(&self,
|
|
font_context: &mut FontContext,
|
|
style: &ComputedValues) -> (Au, Au) {
|
|
let font_style = text::computed_style_to_font_style(style);
|
|
let font_metrics = text::font_metrics_for_style(font_context, &font_style);
|
|
let line_height = text::line_height_from_style(style, &font_metrics);
|
|
let inline_metrics = InlineMetrics::from_font_metrics(&font_metrics, line_height);
|
|
(inline_metrics.block_size_above_baseline, inline_metrics.depth_below_baseline)
|
|
}
|
|
}
|
|
|
|
impl Flow for InlineFlow {
|
|
fn class(&self) -> FlowClass {
|
|
InlineFlowClass
|
|
}
|
|
|
|
fn as_immutable_inline<'a>(&'a self) -> &'a InlineFlow {
|
|
self
|
|
}
|
|
|
|
fn as_inline<'a>(&'a mut self) -> &'a mut InlineFlow {
|
|
self
|
|
}
|
|
|
|
fn bubble_inline_sizes(&mut self, _: &LayoutContext) {
|
|
let _scope = layout_debug_scope!("inline::bubble_inline_sizes {:s}", self.base.debug_id());
|
|
|
|
let writing_mode = self.base.writing_mode;
|
|
for kid in self.base.child_iter() {
|
|
flow::mut_base(kid).floats = Floats::new(writing_mode);
|
|
}
|
|
|
|
let mut intrinsic_inline_sizes = IntrinsicISizes::new();
|
|
for fragment in self.fragments.fragments.mut_iter() {
|
|
debug!("Flow: measuring {}", *fragment);
|
|
|
|
let fragment_intrinsic_inline_sizes =
|
|
fragment.intrinsic_inline_sizes();
|
|
intrinsic_inline_sizes.minimum_inline_size = geometry::max(
|
|
intrinsic_inline_sizes.minimum_inline_size,
|
|
fragment_intrinsic_inline_sizes.minimum_inline_size);
|
|
intrinsic_inline_sizes.preferred_inline_size =
|
|
intrinsic_inline_sizes.preferred_inline_size +
|
|
fragment_intrinsic_inline_sizes.preferred_inline_size;
|
|
}
|
|
|
|
self.base.intrinsic_inline_sizes = intrinsic_inline_sizes;
|
|
}
|
|
|
|
/// Recursively (top-down) determines the actual inline-size of child contexts and fragments. When called
|
|
/// on this context, the context has had its inline-size set by the parent context.
|
|
fn assign_inline_sizes(&mut self, _: &LayoutContext) {
|
|
let _scope = layout_debug_scope!("inline::assign_inline_sizes {:s}", self.base.debug_id());
|
|
|
|
// Initialize content fragment inline-sizes if they haven't been initialized already.
|
|
//
|
|
// TODO: Combine this with `LineBreaker`'s walk in the fragment list, or put this into `Fragment`.
|
|
|
|
debug!("InlineFlow::assign_inline_sizes: floats in: {:?}", self.base.floats);
|
|
|
|
{
|
|
let inline_size = self.base.position.size.inline;
|
|
let this = &mut *self;
|
|
for fragment in this.fragments.fragments.mut_iter() {
|
|
fragment.assign_replaced_inline_size_if_necessary(inline_size);
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Calculate and set the block-size of this flow. See CSS 2.1 § 10.6.1.
|
|
fn assign_block_size(&mut self, ctx: &LayoutContext) {
|
|
let _scope = layout_debug_scope!("inline::assign_block_size {:s}", self.base.debug_id());
|
|
|
|
// Divide the fragments into lines.
|
|
//
|
|
// TODO(#226): Get the CSS `line-block-size` property from the containing block's style to
|
|
// determine minimum line block-size.
|
|
//
|
|
// TODO(#226): Get the CSS `line-block-size` property from each non-replaced inline element to
|
|
// determine its block-size for computing line block-size.
|
|
//
|
|
// TODO(pcwalton): Cache the line scanner?
|
|
debug!("assign_block_size_inline: floats in: {:?}", self.base.floats);
|
|
|
|
// assign block-size for inline fragments
|
|
for fragment in self.fragments.fragments.mut_iter() {
|
|
fragment.assign_replaced_block_size_if_necessary();
|
|
}
|
|
|
|
let scanner_floats = self.base.floats.clone();
|
|
let mut scanner = LineBreaker::new(scanner_floats);
|
|
scanner.scan_for_lines(self, ctx);
|
|
|
|
// All lines use text alignment of the flow.
|
|
let text_align = self.base.flags.text_align();
|
|
|
|
// Now, go through each line and lay out the fragments inside.
|
|
let mut line_distance_from_flow_block_start = Au(0);
|
|
for line in self.lines.mut_iter() {
|
|
// Lay out fragments horizontally.
|
|
InlineFlow::set_horizontal_fragment_positions(&mut self.fragments, line, text_align);
|
|
|
|
// Set the block-start y position of the current line.
|
|
// `line_height_offset` is updated at the end of the previous loop.
|
|
line.bounds.start.b = line_distance_from_flow_block_start;
|
|
|
|
// Calculate the distance from the baseline to the block-start and block-end of the line.
|
|
let mut largest_block_size_above_baseline = self.minimum_block_size_above_baseline;
|
|
let mut largest_depth_below_baseline = self.minimum_depth_below_baseline;
|
|
|
|
// Calculate the largest block-size among fragments with 'top' and 'bottom' values
|
|
// respectively.
|
|
let (mut largest_block_size_for_top_fragments, mut largest_block_size_for_bottom_fragments) =
|
|
(Au(0), Au(0));
|
|
|
|
for fragment_i in each_fragment_index(&line.range) {
|
|
let fragment = self.fragments.fragments.get_mut(fragment_i.to_uint());
|
|
|
|
let InlineMetrics {
|
|
block_size_above_baseline: mut block_size_above_baseline,
|
|
depth_below_baseline: mut depth_below_baseline,
|
|
ascent
|
|
} = fragment.inline_metrics(ctx);
|
|
|
|
// To calculate text-top and text-bottom value when `vertical-align` is involved,
|
|
// we should find the top and bottom of the content area of the parent fragment.
|
|
// "Content area" is defined in CSS 2.1 § 10.6.1.
|
|
//
|
|
// TODO: We should extract em-box info from the font size of the parent and
|
|
// calculate the distances from the baseline to the block-start and the block-end of the
|
|
// parent's content area.
|
|
|
|
// We should calculate the distance from baseline to the top of parent's content
|
|
// area. But for now we assume it's the font size.
|
|
//
|
|
// CSS 2.1 does not state which font to use. Previous versions of the code used
|
|
// the parent's font; this code uses the current font.
|
|
let parent_text_top = fragment.style().get_font().font_size;
|
|
|
|
// We should calculate the distance from baseline to the bottom of the parent's
|
|
// content area. But for now we assume it's zero.
|
|
let parent_text_bottom = Au(0);
|
|
|
|
// Calculate the final block-size above the baseline for this fragment.
|
|
//
|
|
// The no-update flag decides whether `largest_block-size_for_top_fragments` and
|
|
// `largest_block-size_for_bottom_fragments` are to be updated or not. This will be set
|
|
// if and only if the fragment has `vertical-align` set to `top` or `bottom`.
|
|
let (distance_from_baseline, no_update_flag) =
|
|
InlineFlow::distance_from_baseline(
|
|
fragment,
|
|
ascent,
|
|
parent_text_top,
|
|
parent_text_bottom,
|
|
&mut block_size_above_baseline,
|
|
&mut depth_below_baseline,
|
|
&mut largest_block_size_for_top_fragments,
|
|
&mut largest_block_size_for_bottom_fragments,
|
|
ctx);
|
|
|
|
// Unless the current fragment has `vertical-align` set to `top` or `bottom`,
|
|
// `largest_block-size_above_baseline` and `largest_depth_below_baseline` are updated.
|
|
if !no_update_flag {
|
|
largest_block_size_above_baseline = Au::max(block_size_above_baseline,
|
|
largest_block_size_above_baseline);
|
|
largest_depth_below_baseline = Au::max(depth_below_baseline,
|
|
largest_depth_below_baseline);
|
|
}
|
|
|
|
// Temporarily use `fragment.border_box.start.b` to mean "the distance from the
|
|
// baseline". We will assign the real value later.
|
|
fragment.border_box.start.b = distance_from_baseline
|
|
}
|
|
|
|
// Calculate the distance from the baseline to the top of the largest fragment with a
|
|
// value for `bottom`. Then, if necessary, update `largest_block-size_above_baseline`.
|
|
largest_block_size_above_baseline =
|
|
Au::max(largest_block_size_above_baseline,
|
|
largest_block_size_for_bottom_fragments - largest_depth_below_baseline);
|
|
|
|
// Calculate the distance from baseline to the bottom of the largest fragment with a value
|
|
// for `top`. Then, if necessary, update `largest_depth_below_baseline`.
|
|
largest_depth_below_baseline =
|
|
Au::max(largest_depth_below_baseline,
|
|
largest_block_size_for_top_fragments - largest_block_size_above_baseline);
|
|
|
|
// Now, the distance from the logical block-start of the line to the baseline can be
|
|
// computed as `largest_block-size_above_baseline`.
|
|
let baseline_distance_from_block_start = largest_block_size_above_baseline;
|
|
|
|
// Compute the final positions in the block direction of each fragment. Recall that
|
|
// `fragment.border_box.start.b` was set to the distance from the baseline above.
|
|
for fragment_i in each_fragment_index(&line.range) {
|
|
let fragment = self.fragments.get_mut(fragment_i.to_uint());
|
|
match fragment.vertical_align() {
|
|
vertical_align::top => {
|
|
fragment.border_box.start.b = fragment.border_box.start.b +
|
|
line_distance_from_flow_block_start
|
|
}
|
|
vertical_align::bottom => {
|
|
fragment.border_box.start.b = fragment.border_box.start.b +
|
|
line_distance_from_flow_block_start + baseline_distance_from_block_start +
|
|
largest_depth_below_baseline
|
|
}
|
|
_ => {
|
|
fragment.border_box.start.b = fragment.border_box.start.b +
|
|
line_distance_from_flow_block_start + baseline_distance_from_block_start
|
|
}
|
|
}
|
|
}
|
|
|
|
// This is used to set the block-start y position of the next line in the next loop.
|
|
line.bounds.size.block = largest_block_size_above_baseline + largest_depth_below_baseline;
|
|
line_distance_from_flow_block_start = line_distance_from_flow_block_start + line.bounds.size.block;
|
|
} // End of `lines.each` loop.
|
|
|
|
self.base.position.size.block = match self.lines.as_slice().last() {
|
|
Some(ref last_line) => last_line.bounds.start.b + last_line.bounds.size.block,
|
|
None => Au::new(0)
|
|
};
|
|
|
|
self.base.floats = scanner.floats();
|
|
self.base.floats.translate(LogicalSize::new(
|
|
self.base.writing_mode, Au::new(0), -self.base.position.size.block));
|
|
}
|
|
|
|
fn compute_absolute_position(&mut self) {
|
|
for f in self.fragments.fragments.mut_iter() {
|
|
match f.specific {
|
|
InlineBlockFragment(ref mut info) => {
|
|
let block_flow = info.flow_ref.get_mut().as_block();
|
|
|
|
// FIXME(#2795): Get the real container size
|
|
let container_size = Size2D::zero();
|
|
block_flow.base.abs_position = self.base.abs_position +
|
|
f.border_box.start.to_physical(self.base.writing_mode, container_size);
|
|
}
|
|
_ => {}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
impl fmt::Show for InlineFlow {
|
|
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
|
|
try!(write!(f, "InlineFlow"));
|
|
for (i, fragment) in self.fragments.fragments.iter().enumerate() {
|
|
if i == 0 {
|
|
try!(write!(f, ": {}", fragment))
|
|
} else {
|
|
try!(write!(f, ", {}", fragment))
|
|
}
|
|
}
|
|
Ok(())
|
|
}
|
|
}
|
|
|
|
#[deriving(Clone)]
|
|
pub struct InlineFragmentContext {
|
|
pub styles: Vec<Arc<ComputedValues>>,
|
|
}
|
|
|
|
impl InlineFragmentContext {
|
|
pub fn new() -> InlineFragmentContext {
|
|
InlineFragmentContext {
|
|
styles: vec!()
|
|
}
|
|
}
|
|
}
|
|
|
|
/// BSize above the baseline, depth below the baseline, and ascent for a fragment. See CSS 2.1 §
|
|
/// 10.8.1.
|
|
pub struct InlineMetrics {
|
|
pub block_size_above_baseline: Au,
|
|
pub depth_below_baseline: Au,
|
|
pub ascent: Au,
|
|
}
|
|
|
|
impl InlineMetrics {
|
|
/// Calculates inline metrics from font metrics and line block-size per CSS 2.1 § 10.8.1.
|
|
#[inline]
|
|
pub fn from_font_metrics(font_metrics: &FontMetrics, line_height: Au) -> InlineMetrics {
|
|
let leading = line_height - (font_metrics.ascent + font_metrics.descent);
|
|
InlineMetrics {
|
|
block_size_above_baseline: font_metrics.ascent + leading.scale_by(0.5),
|
|
depth_below_baseline: font_metrics.descent + leading.scale_by(0.5),
|
|
ascent: font_metrics.ascent,
|
|
}
|
|
}
|
|
|
|
/// Calculates inline metrics from font metrics and line block-size per CSS 2.1 § 10.8.1.
|
|
#[inline]
|
|
pub fn from_block_height(font_metrics: &FontMetrics, block_height: Au) -> InlineMetrics {
|
|
let leading = block_height - (font_metrics.ascent + font_metrics.descent);
|
|
InlineMetrics {
|
|
block_size_above_baseline: font_metrics.ascent + leading.scale_by(0.5),
|
|
depth_below_baseline: font_metrics.descent + leading.scale_by(0.5),
|
|
ascent: font_metrics.ascent + leading.scale_by(0.5),
|
|
}
|
|
}
|
|
}
|
|
|