Struct layout_2020::flow::float::FloatContext

pub struct FloatContext {
    pub bands: FloatBandTree,
    pub ceiling_from_floats: Au,
    pub ceiling_from_non_floats: Au,
    pub containing_block_info: ContainingBlockPositionInfo,
    pub clear_left_position: Au,
    pub clear_right_position: Au,
}

Data kept during layout about the floats in a given block formatting context.

This is a persistent data structure. Each float has its own private copy of the float context, although such copies may share portions of the bands tree.

Fields

bands: FloatBandTree

A persistent AA tree of float bands.

This tree is immutable; modification operations return the new tree, which may share nodes with previous versions of the tree.

ceiling_from_floats: Au

The block-direction “ceiling” defined by the placement of other floated content of this FloatContext. No new floats can be placed at a lower block start than this value.

ceiling_from_non_floats: Au

The block-direction “ceiling” defined by the placement of non-floated content that precedes floated content in the document. Note that this may actually decrease as content is laid out in the case that content overflows its container.

containing_block_info: ContainingBlockPositionInfo

Details about the position of the containing block relative to the independent block formatting context that contains all of the floats this FloatContext positions.

clear_left_position: Au

The (logically) lowest margin edge of the last left float.

clear_right_position: Au

The (logically) lowest margin edge of the last right float.

Implementations

impl FloatContext

pub fn new(max_inline_size: Au) -> Self

Returns a new float context representing a containing block with the given content inline-size.

pub fn set_ceiling_from_non_floats(&mut self, new_ceiling: Au)

(Logically) lowers the ceiling to at least new_ceiling units.

If the ceiling is already logically lower (i.e. larger) than this, does nothing.

fn ceiling(&mut self) -> Au

The “ceiling” used for float placement. This is the minimum block position value that should be used for placing any new float.

pub(crate) fn place_object( &self, object: &PlacementInfo, ceiling: Au, ) -> LogicalVec2<Au>

Determines where a float with the given placement would go, but leaves the float context unmodified. Returns the start corner of its margin box.

This should be used for placing inline elements and block formatting contexts so that they don’t collide with floats.

pub fn add_float(&mut self, new_float: &PlacementInfo) -> LogicalVec2<Au>

Places a new float and adds it to the list. Returns the start corner of its margin box.

Trait Implementations

impl Clone for FloatContext

fn clone(&self) -> FloatContext

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for FloatContext

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.