/* 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/. */
//! Utilities for querying the layout, as needed by the layout thread.
use app_units::Au;
use construct::ConstructionResult;
use euclid::point::Point2D;
use euclid::rect::Rect;
use euclid::size::Size2D;
use flow::{self, Flow};
use fragment::{Fragment, FragmentBorderBoxIterator, SpecificFragmentInfo};
use gfx::display_list::{DisplayItemMetadata, DisplayList, OpaqueNode, ScrollOffsetMap};
use ipc_channel::ipc::IpcSender;
use opaque_node::OpaqueNodeMethods;
use script_layout_interface::rpc::{ContentBoxResponse, ContentBoxesResponse};
use script_layout_interface::rpc::{HitTestResponse, LayoutRPC};
use script_layout_interface::rpc::{MarginStyleResponse, NodeGeometryResponse};
use script_layout_interface::rpc::{NodeOverflowResponse, OffsetParentResponse};
use script_layout_interface::rpc::ResolvedStyleResponse;
use script_layout_interface::wrapper_traits::{LayoutNode, ThreadSafeLayoutElement, ThreadSafeLayoutNode};
use script_traits::LayoutMsg as ConstellationMsg;
use script_traits::UntrustedNodeAddress;
use sequential;
use servo_atoms::Atom;
use std::cmp::{min, max};
use std::ops::Deref;
use std::sync::{Arc, Mutex};
use style::computed_values;
use style::context::StyleContext;
use style::logical_geometry::{WritingMode, BlockFlowDirection, InlineBaseDirection};
use style::properties::longhands::{display, position};
use style::properties::style_structs;
use style::selector_parser::PseudoElement;
use style::stylist::Stylist;
use style_traits::ToCss;
use style_traits::cursor::Cursor;
use wrapper::{LayoutNodeHelpers, LayoutNodeLayoutData};
/// Mutable data belonging to the LayoutThread.
///
/// This needs to be protected by a mutex so we can do fast RPCs.
pub struct LayoutThreadData {
/// The channel on which messages can be sent to the constellation.
pub constellation_chan: IpcSender<ConstellationMsg>,
/// The root stacking context.
pub display_list: Option<Arc<DisplayList>>,
/// Performs CSS selector matching and style resolution.
pub stylist: Arc<Stylist>,
/// A queued response for the union of the content boxes of a node.
pub content_box_response: Rect<Au>,
/// A queued response for the content boxes of a node.
pub content_boxes_response: Vec<Rect<Au>>,
/// A queued response for the client {top, left, width, height} of a node in pixels.
pub client_rect_response: Rect<i32>,
/// A queued response for the node at a given point
pub hit_test_response: (Option<DisplayItemMetadata>, bool),
/// A pair of overflow property in x and y
pub overflow_response: NodeOverflowResponse,
/// A queued response for the scroll {top, left, width, height} of a node in pixels.
pub scroll_area_response: Rect<i32>,
/// A queued response for the resolved style property of an element.
pub resolved_style_response: Option<String>,
/// A queued response for the offset parent/rect of a node.
pub offset_parent_response: OffsetParentResponse,
/// A queued response for the offset parent/rect of a node.
pub margin_style_response: MarginStyleResponse,
/// Scroll offsets of stacking contexts. This will only be populated if WebRender is in use.
pub stacking_context_scroll_offsets: ScrollOffsetMap,
}
pub struct LayoutRPCImpl(pub Arc<Mutex<LayoutThreadData>>);
// https://drafts.csswg.org/cssom-view/#overflow-directions
fn overflow_direction(writing_mode: &WritingMode) -> OverflowDirection {
match (writing_mode.block_flow_direction(), writing_mode.inline_base_direction()) {
(BlockFlowDirection::TopToBottom, InlineBaseDirection::LeftToRight) |
(BlockFlowDirection::LeftToRight, InlineBaseDirection::LeftToRight) => OverflowDirection::RightAndDown,
(BlockFlowDirection::TopToBottom, InlineBaseDirection::RightToLeft) |
(BlockFlowDirection::RightToLeft, InlineBaseDirection::LeftToRight) => OverflowDirection::LeftAndDown,
(BlockFlowDirection::RightToLeft, InlineBaseDirection::RightToLeft) => OverflowDirection::LeftAndUp,
(BlockFlowDirection::LeftToRight, InlineBaseDirection::RightToLeft) => OverflowDirection::RightAndUp
}
}
impl LayoutRPC for LayoutRPCImpl {
// The neat thing here is that in order to answer the following two queries we only
// need to compare nodes for equality. Thus we can safely work only with `OpaqueNode`.
fn content_box(&self) -> ContentBoxResponse {
let &LayoutRPCImpl(ref rw_data) = self;
let rw_data = rw_data.lock().unwrap();
ContentBoxResponse(rw_data.content_box_response)
}
/// Requests the dimensions of all the content boxes, as in the `getClientRects()` call.
fn content_boxes(&self) -> ContentBoxesResponse {
let &LayoutRPCImpl(ref rw_data) = self;
let rw_data = rw_data.lock().unwrap();
ContentBoxesResponse(rw_data.content_boxes_response.clone())
}
/// Requests the node containing the point of interest.
fn hit_test(&self) -> HitTestResponse {
let &LayoutRPCImpl(ref rw_data) = self;
let rw_data = rw_data.lock().unwrap();
let &(ref result, update_cursor) = &rw_data.hit_test_response;
if update_cursor {
// Compute the new cursor.
let cursor = match *result {
None => Cursor::Default,
Some(dim) => dim.pointing.unwrap(),
};
rw_data.constellation_chan.send(ConstellationMsg::SetCursor(cursor)).unwrap();
}
HitTestResponse {
node_address: result.map(|dim| dim.node.to_untrusted_node_address()),
}
}
fn nodes_from_point(&self,
page_point: Point2D<f32>,
client_point: Point2D<f32>) -> Vec<UntrustedNodeAddress> {
let page_point = Point2D::new(Au::from_f32_px(page_point.x),
Au::from_f32_px(page_point.y));
let client_point = Point2D::new(Au::from_f32_px(client_point.x),
Au::from_f32_px(client_point.y));
let nodes_from_point_list = {
let &LayoutRPCImpl(ref rw_data) = self;
let rw_data = rw_data.lock().unwrap();
let result = match rw_data.display_list {
None => panic!("Tried to hit test without a DisplayList"),
Some(ref display_list) => {
display_list.hit_test(&page_point,
&client_point,
&rw_data.stacking_context_scroll_offsets)
}
};
result
};
nodes_from_point_list.iter()
.rev()
.map(|metadata| metadata.node.to_untrusted_node_address())
.collect()
}
fn node_geometry(&self) -> NodeGeometryResponse {
let &LayoutRPCImpl(ref rw_data) = self;
let rw_data = rw_data.lock().unwrap();
NodeGeometryResponse {
client_rect: rw_data.client_rect_response
}
}
fn node_overflow(&self) -> NodeOverflowResponse {
NodeOverflowResponse(self.0.lock().unwrap().overflow_response.0)
}
fn node_scroll_area(&self) -> NodeGeometryResponse {
NodeGeometryResponse {
client_rect: self.0.lock().unwrap().scroll_area_response
}
}
/// Retrieves the resolved value for a CSS style property.
fn resolved_style(&self) -> ResolvedStyleResponse {
let &LayoutRPCImpl(ref rw_data) = self;
let rw_data = rw_data.lock().unwrap();
ResolvedStyleResponse(rw_data.resolved_style_response.clone())
}
fn offset_parent(&self) -> OffsetParentResponse {
let &LayoutRPCImpl(ref rw_data) = self;
let rw_data = rw_data.lock().unwrap();
rw_data.offset_parent_response.clone()
}
fn margin_style(&self) -> MarginStyleResponse {
let &LayoutRPCImpl(ref rw_data) = self;
let rw_data = rw_data.lock().unwrap();
rw_data.margin_style_response.clone()
}
}
struct UnioningFragmentBorderBoxIterator {
node_address: OpaqueNode,
rect: Option<Rect<Au>>,
}
impl UnioningFragmentBorderBoxIterator {
fn new(node_address: OpaqueNode) -> UnioningFragmentBorderBoxIterator {
UnioningFragmentBorderBoxIterator {
node_address: node_address,
rect: None
}
}
}
impl FragmentBorderBoxIterator for UnioningFragmentBorderBoxIterator {
fn process(&mut self, _: &Fragment, _: i32, border_box: &Rect<Au>) {
self.rect = match self.rect {
Some(rect) => {
Some(rect.union(border_box))
}
None => {
Some(*border_box)
}
};
}
fn should_process(&mut self, fragment: &Fragment) -> bool {
fragment.contains_node(self.node_address)
}
}
struct CollectingFragmentBorderBoxIterator {
node_address: OpaqueNode,
rects: Vec<Rect<Au>>,
}
impl CollectingFragmentBorderBoxIterator {
fn new(node_address: OpaqueNode) -> CollectingFragmentBorderBoxIterator {
CollectingFragmentBorderBoxIterator {
node_address: node_address,
rects: Vec::new(),
}
}
}
impl FragmentBorderBoxIterator for CollectingFragmentBorderBoxIterator {
fn process(&mut self, _: &Fragment, _: i32, border_box: &Rect<Au>) {
self.rects.push(*border_box);
}
fn should_process(&mut self, fragment: &Fragment) -> bool {
fragment.contains_node(self.node_address)
}
}
enum Side {
Left,
Right,
Bottom,
Top
}
enum MarginPadding {
Margin,
Padding
}
enum PositionProperty {
Left,
Right,
Top,
Bottom,
Width,
Height,
}
#[derive(Debug)]
enum OverflowDirection {
RightAndDown,
LeftAndDown,
LeftAndUp,
RightAndUp,
}
struct PositionRetrievingFragmentBorderBoxIterator {
node_address: OpaqueNode,
result: Option<Au>,
position: Point2D<Au>,
property: PositionProperty,
}
impl PositionRetrievingFragmentBorderBoxIterator {
fn new(node_address: OpaqueNode,
property: PositionProperty,
position: Point2D<Au>) -> PositionRetrievingFragmentBorderBoxIterator {
PositionRetrievingFragmentBorderBoxIterator {
node_address: node_address,
position: position,
property: property,
result: None,
}
}
}
impl FragmentBorderBoxIterator for PositionRetrievingFragmentBorderBoxIterator {
fn process(&mut self, fragment: &Fragment, _: i32, border_box: &Rect<Au>) {
let border_padding = fragment.border_padding.to_physical(fragment.style.writing_mode);
self.result =
Some(match self.property {
PositionProperty::Left => self.position.x,
PositionProperty::Top => self.position.y,
PositionProperty::Width => border_box.size.width - border_padding.horizontal(),
PositionProperty::Height => border_box.size.height - border_padding.vertical(),
// TODO: the following 2 calculations are completely wrong.
// They should return the difference between the parent's and this
// fragment's border boxes.
PositionProperty::Right => border_box.max_x() + self.position.x,
PositionProperty::Bottom => border_box.max_y() + self.position.y,
});
}
fn should_process(&mut self, fragment: &Fragment) -> bool {
fragment.contains_node(self.node_address)
}
}
struct MarginRetrievingFragmentBorderBoxIterator {
node_address: OpaqueNode,
result: Option<Au>,
writing_mode: WritingMode,
margin_padding: MarginPadding,
side: Side,
}
impl MarginRetrievingFragmentBorderBoxIterator {
fn new(node_address: OpaqueNode, side: Side, margin_padding:
MarginPadding, writing_mode: WritingMode) -> MarginRetrievingFragmentBorderBoxIterator {
MarginRetrievingFragmentBorderBoxIterator {
node_address: node_address,
side: side,
margin_padding: margin_padding,
result: None,
writing_mode: writing_mode,
}
}
}
impl FragmentBorderBoxIterator for MarginRetrievingFragmentBorderBoxIterator {
fn process(&mut self, fragment: &Fragment, _: i32, _: &Rect<Au>) {
let rect = match self.margin_padding {
MarginPadding::Margin => &fragment.margin,
MarginPadding::Padding => &fragment.border_padding
};
self.result = Some(match self.side {
Side::Left => rect.left(self.writing_mode),
Side::Right => rect.right(self.writing_mode),
Side::Bottom => rect.bottom(self.writing_mode),
Side::Top => rect.top(self.writing_mode)
});
}
fn should_process(&mut self, fragment: &Fragment) -> bool {
fragment.contains_node(self.node_address)
}
}
pub fn process_content_box_request<N: LayoutNode>(
requested_node: N, layout_root: &mut Flow) -> Rect<Au> {
// FIXME(pcwalton): This has not been updated to handle the stacking context relative
// stuff. So the position is wrong in most cases.
let mut iterator = UnioningFragmentBorderBoxIterator::new(requested_node.opaque());
sequential::iterate_through_flow_tree_fragment_border_boxes(layout_root, &mut iterator);
match iterator.rect {
Some(rect) => rect,
None => Rect::zero()
}
}
pub fn process_content_boxes_request<N: LayoutNode>(requested_node: N, layout_root: &mut Flow)
-> Vec<Rect<Au>> {
// FIXME(pcwalton): This has not been updated to handle the stacking context relative
// stuff. So the position is wrong in most cases.
let mut iterator = CollectingFragmentBorderBoxIterator::new(requested_node.opaque());
sequential::iterate_through_flow_tree_fragment_border_boxes(layout_root, &mut iterator);
iterator.rects
}
struct FragmentLocatingFragmentIterator {
node_address: OpaqueNode,
client_rect: Rect<i32>,
}
impl FragmentLocatingFragmentIterator {
fn new(node_address: OpaqueNode) -> FragmentLocatingFragmentIterator {
FragmentLocatingFragmentIterator {
node_address: node_address,
client_rect: Rect::zero()
}
}
}
struct UnioningFragmentScrollAreaIterator {
node_address: OpaqueNode,
union_rect: Rect<i32>,
origin_rect: Rect<i32>,
level: Option<i32>,
is_child: bool,
overflow_direction: OverflowDirection
}
impl UnioningFragmentScrollAreaIterator {
fn new(node_address: OpaqueNode) -> UnioningFragmentScrollAreaIterator {
UnioningFragmentScrollAreaIterator {
node_address: node_address,
union_rect: Rect::zero(),
origin_rect: Rect::zero(),
level: None,
is_child: false,
overflow_direction: OverflowDirection::RightAndDown
}
}
}
struct ParentBorderBoxInfo {
node_address: OpaqueNode,
border_box: Rect<Au>,
}
struct ParentOffsetBorderBoxIterator {
node_address: OpaqueNode,
last_level: i32,
has_found_node: bool,
node_border_box: Rect<Au>,
parent_nodes: Vec<Option<ParentBorderBoxInfo>>,
}
impl ParentOffsetBorderBoxIterator {
fn new(node_address: OpaqueNode) -> ParentOffsetBorderBoxIterator {
ParentOffsetBorderBoxIterator {
node_address: node_address,
last_level: -1,
has_found_node: false,
node_border_box: Rect::zero(),
parent_nodes: Vec::new(),
}
}
}
impl FragmentBorderBoxIterator for FragmentLocatingFragmentIterator {
fn process(&mut self, fragment: &Fragment, _: i32, border_box: &Rect<Au>) {
let style_structs::Border {
border_top_width: top_width,
border_right_width: right_width,
border_bottom_width: bottom_width,
border_left_width: left_width,
..
} = *fragment.style.get_border();
self.client_rect.origin.y = top_width.to_px();
self.client_rect.origin.x = left_width.to_px();
self.client_rect.size.width = (border_box.size.width - left_width - right_width).to_px();
self.client_rect.size.height = (border_box.size.height - top_width - bottom_width).to_px();
}
fn should_process(&mut self, fragment: &Fragment) -> bool {
fragment.node == self.node_address
}
}
// https://drafts.csswg.org/cssom-view/#scrolling-area
impl FragmentBorderBoxIterator for UnioningFragmentScrollAreaIterator {
fn process(&mut self, fragment: &Fragment, level: i32, border_box: &Rect<Au>) {
// In cases in which smaller child elements contain less padding than the parent
// the a union of the two elements padding rectangles could result in an unwanted
// increase in size. To work around this, we store the original elements padding
// rectangle as `origin_rect` and the union of all child elements padding and
// margin rectangles as `union_rect`.
let style_structs::Border {
border_top_width: top_border,
border_right_width: right_border,
border_bottom_width: bottom_border,
border_left_width: left_border,
..
} = *fragment.style.get_border();
let right_padding = (border_box.size.width - right_border - left_border).to_px();
let bottom_padding = (border_box.size.height - bottom_border - top_border).to_px();
let top_padding = top_border.to_px();
let left_padding = left_border.to_px();
match self.level {
Some(start_level) if level <= start_level => { self.is_child = false; }
Some(_) => {
let padding = Rect::new(Point2D::new(left_padding, top_padding),
Size2D::new(right_padding, bottom_padding));
let top_margin = fragment.margin.top(fragment.style.writing_mode).to_px();
let left_margin = fragment.margin.left(fragment.style.writing_mode).to_px();
let bottom_margin = fragment.margin.bottom(fragment.style.writing_mode).to_px();
let right_margin = fragment.margin.right(fragment.style.writing_mode).to_px();
let margin = Rect::new(Point2D::new(left_margin, top_margin),
Size2D::new(right_margin, bottom_margin));
self.union_rect = self.union_rect.union(&margin).union(&padding);
}
None => {
self.level = Some(level);
self.is_child = true;
self.overflow_direction = overflow_direction(&fragment.style.writing_mode);
self.origin_rect = Rect::new(Point2D::new(left_padding, top_padding),
Size2D::new(right_padding, bottom_padding));
},
};
}
fn should_process(&mut self, fragment: &Fragment) -> bool {
fragment.contains_node(self.node_address) || self.is_child
}
}
// https://drafts.csswg.org/cssom-view/#extensions-to-the-htmlelement-interface
impl FragmentBorderBoxIterator for ParentOffsetBorderBoxIterator {
fn process(&mut self, fragment: &Fragment, level: i32, border_box: &Rect<Au>) {
if fragment.node == self.node_address {
// Found the fragment in the flow tree that matches the
// DOM node being looked for.
self.has_found_node = true;
self.node_border_box = *border_box;
// offsetParent returns null if the node is fixed.
if fragment.style.get_box().position == computed_values::position::T::fixed {
self.parent_nodes.clear();
}
} else if level > self.last_level {
// TODO(gw): Is there a less fragile way of checking whether this
// fragment is the body element, rather than just checking that
// the parent nodes stack contains the root node only?
let is_body_element = self.parent_nodes.len() == 1;
let is_valid_parent = match (is_body_element,
fragment.style.get_box().position,
&fragment.specific) {
// Spec says it's valid if any of these are true:
// 1) Is the body element
// 2) Is static position *and* is a table or table cell
// 3) Is not static position
(true, _, _) |
(false, computed_values::position::T::static_, &SpecificFragmentInfo::Table) |
(false, computed_values::position::T::static_, &SpecificFragmentInfo::TableCell) |
(false, computed_values::position::T::absolute, _) |
(false, computed_values::position::T::relative, _) |
(false, computed_values::position::T::fixed, _) => true,
// Otherwise, it's not a valid parent
(false, computed_values::position::T::static_, _) => false,
};
let parent_info = if is_valid_parent {
Some(ParentBorderBoxInfo {
border_box: *border_box,
node_address: fragment.node,
})
} else {
None
};
self.parent_nodes.push(parent_info);
} else if level < self.last_level {
self.parent_nodes.pop();
}
}
fn should_process(&mut self, _: &Fragment) -> bool {
!self.has_found_node
}
}
pub fn process_node_geometry_request<N: LayoutNode>(requested_node: N, layout_root: &mut Flow)
-> Rect<i32> {
let mut iterator = FragmentLocatingFragmentIterator::new(requested_node.opaque());
sequential::iterate_through_flow_tree_fragment_border_boxes(layout_root, &mut iterator);
iterator.client_rect
}
pub fn process_node_scroll_area_request< N: LayoutNode>(requested_node: N, layout_root: &mut Flow)
-> Rect<i32> {
let mut iterator = UnioningFragmentScrollAreaIterator::new(requested_node.opaque());
sequential::iterate_through_flow_tree_fragment_border_boxes(layout_root, &mut iterator);
match iterator.overflow_direction {
OverflowDirection::RightAndDown => {
let right = max(iterator.union_rect.size.width, iterator.origin_rect.size.width);
let bottom = max(iterator.union_rect.size.height, iterator.origin_rect.size.height);
Rect::new(iterator.origin_rect.origin, Size2D::new(right, bottom))
},
OverflowDirection::LeftAndDown => {
let bottom = max(iterator.union_rect.size.height, iterator.origin_rect.size.height);
let left = max(iterator.union_rect.origin.x, iterator.origin_rect.origin.x);
Rect::new(Point2D::new(left, iterator.origin_rect.origin.y),
Size2D::new(iterator.origin_rect.size.width, bottom))
},
OverflowDirection::LeftAndUp => {
let top = min(iterator.union_rect.origin.y, iterator.origin_rect.origin.y);
let left = min(iterator.union_rect.origin.x, iterator.origin_rect.origin.x);
Rect::new(Point2D::new(left, top), iterator.origin_rect.size)
},
OverflowDirection::RightAndUp => {
let top = min(iterator.union_rect.origin.y, iterator.origin_rect.origin.y);
let right = max(iterator.union_rect.size.width, iterator.origin_rect.size.width);
Rect::new(Point2D::new(iterator.origin_rect.origin.x, top),
Size2D::new(right, iterator.origin_rect.size.height))
}
}
}
/// Ensures that a node's data, and all its parents' is initialized. This is
/// needed to resolve style lazily.
fn ensure_node_data_initialized<N: LayoutNode>(node: &N) {
let mut cur = Some(node.clone());
while let Some(current) = cur {
if current.borrow_layout_data().is_some() {
break;
}
current.initialize_data();
cur = current.parent_node();
}
}
/// Return the resolved value of property for a given (pseudo)element.
/// https://drafts.csswg.org/cssom/#resolved-value
pub fn process_resolved_style_request<'a, N, C>(requested_node: N,
style_context: &'a C,
pseudo: &Option<PseudoElement>,
property: &Atom,
layout_root: &mut Flow) -> Option<String>
where N: LayoutNode,
C: StyleContext<'a>
{
use style::traversal::ensure_element_styled;
// This node might have display: none, or it's style might be not up to
// date, so we might need to do style recalc.
//
// FIXME(emilio): Is a bit shame we have to do this instead of in style.
ensure_node_data_initialized(&requested_node);
ensure_element_styled(requested_node.as_element().unwrap(), style_context);
let layout_el = requested_node.to_threadsafe().as_element().unwrap();
let layout_el = match *pseudo {
Some(PseudoElement::Before) => layout_el.get_before_pseudo(),
Some(PseudoElement::After) => layout_el.get_after_pseudo(),
Some(PseudoElement::DetailsSummary) |
Some(PseudoElement::DetailsContent) |
Some(PseudoElement::Selection) => None,
_ => Some(layout_el)
};
let layout_el = match layout_el {
None => {
// The pseudo doesn't exist, return nothing. Chrome seems to query
// the element itself in this case, Firefox uses the resolved value.
// https://www.w3.org/Bugs/Public/show_bug.cgi?id=29006
return None;
}
Some(layout_el) => layout_el
};
let style = &*layout_el.resolved_style();
let positioned = match style.get_box().position {
position::computed_value::T::relative |
/*position::computed_value::T::sticky |*/
position::computed_value::T::fixed |
position::computed_value::T::absolute => true,
_ => false
};
//TODO: determine whether requested property applies to the element.
// eg. width does not apply to non-replaced inline elements.
// Existing browsers disagree about when left/top/right/bottom apply
// (Chrome seems to think they never apply and always returns resolved values).
// There are probably other quirks.
let applies = true;
fn used_value_for_position_property<N: LayoutNode>(
layout_el: <N::ConcreteThreadSafeLayoutNode as ThreadSafeLayoutNode>::ConcreteThreadSafeLayoutElement,
layout_root: &mut Flow,
requested_node: N,
property: &Atom) -> Option<String> {
let maybe_data = layout_el.borrow_layout_data();
let position = maybe_data.map_or(Point2D::zero(), |data| {
match (*data).flow_construction_result {
ConstructionResult::Flow(ref flow_ref, _) =>
flow::base(flow_ref.deref()).stacking_relative_position,
// TODO(dzbarsky) search parents until we find node with a flow ref.
// https://github.com/servo/servo/issues/8307
_ => Point2D::zero()
}
});
let property = match *property {
atom!("bottom") => PositionProperty::Bottom,
atom!("top") => PositionProperty::Top,
atom!("left") => PositionProperty::Left,
atom!("right") => PositionProperty::Right,
atom!("width") => PositionProperty::Width,
atom!("height") => PositionProperty::Height,
_ => unreachable!()
};
let mut iterator =
PositionRetrievingFragmentBorderBoxIterator::new(requested_node.opaque(),
property,
position);
sequential::iterate_through_flow_tree_fragment_border_boxes(layout_root,
&mut iterator);
iterator.result.map(|r| r.to_css_string())
}
// TODO: we will return neither the computed nor used value for margin and padding.
// Firefox returns blank strings for the computed value of shorthands,
// so this should be web-compatible.
match *property {
atom!("margin-bottom") | atom!("margin-top") |
atom!("margin-left") | atom!("margin-right") |
atom!("padding-bottom") | atom!("padding-top") |
atom!("padding-left") | atom!("padding-right")
if applies && style.get_box().display != display::computed_value::T::none => {
let (margin_padding, side) = match *property {
atom!("margin-bottom") => (MarginPadding::Margin, Side::Bottom),
atom!("margin-top") => (MarginPadding::Margin, Side::Top),
atom!("margin-left") => (MarginPadding::Margin, Side::Left),
atom!("margin-right") => (MarginPadding::Margin, Side::Right),
atom!("padding-bottom") => (MarginPadding::Padding, Side::Bottom),
atom!("padding-top") => (MarginPadding::Padding, Side::Top),
atom!("padding-left") => (MarginPadding::Padding, Side::Left),
atom!("padding-right") => (MarginPadding::Padding, Side::Right),
_ => unreachable!()
};
let mut iterator =
MarginRetrievingFragmentBorderBoxIterator::new(requested_node.opaque(),
side,
margin_padding,
style.writing_mode);
sequential::iterate_through_flow_tree_fragment_border_boxes(layout_root,
&mut iterator);
iterator.result.map(|r| r.to_css_string())
},
atom!("bottom") | atom!("top") | atom!("right") |
atom!("left")
if applies && positioned && style.get_box().display !=
display::computed_value::T::none => {
used_value_for_position_property(layout_el, layout_root, requested_node, property)
}
atom!("width") | atom!("height")
if applies && style.get_box().display !=
display::computed_value::T::none => {
used_value_for_position_property(layout_el, layout_root, requested_node, property)
}
// FIXME: implement used value computation for line-height
ref property => {
style.computed_value_to_string(&*property).ok()
}
}
}
pub fn process_offset_parent_query<N: LayoutNode>(requested_node: N, layout_root: &mut Flow)
-> OffsetParentResponse {
let mut iterator = ParentOffsetBorderBoxIterator::new(requested_node.opaque());
sequential::iterate_through_flow_tree_fragment_border_boxes(layout_root, &mut iterator);
let parent_info_index = iterator.parent_nodes.iter().rposition(|info| info.is_some());
match parent_info_index {
Some(parent_info_index) => {
let parent = iterator.parent_nodes[parent_info_index].as_ref().unwrap();
let origin = iterator.node_border_box.origin - parent.border_box.origin;
let size = iterator.node_border_box.size;
OffsetParentResponse {
node_address: Some(parent.node_address.to_untrusted_node_address()),
rect: Rect::new(origin, size),
}
}
None => {
OffsetParentResponse::empty()
}
}
}
pub fn process_node_overflow_request<N: LayoutNode>(requested_node: N) -> NodeOverflowResponse {
let layout_node = requested_node.to_threadsafe();
let style = &*layout_node.as_element().unwrap().resolved_style();
let style_box = style.get_box();
NodeOverflowResponse(Some((Point2D::new(style_box.overflow_x, style_box.overflow_y.0))))
}
pub fn process_margin_style_query<N: LayoutNode>(requested_node: N)
-> MarginStyleResponse {
let layout_node = requested_node.to_threadsafe();
let style = &*layout_node.as_element().unwrap().resolved_style();
let margin = style.get_margin();
MarginStyleResponse {
top: margin.margin_top,
right: margin.margin_right,
bottom: margin.margin_bottom,
left: margin.margin_left,
}
}