Struct TextSelection 

pub struct TextSelection {
    pub dom_id: DomId,
    pub anchor: SelectionAnchor,
    pub focus: SelectionFocus,
    pub affected_nodes: BTreeMap<NodeId, Vec<SelectionRange>>,
    pub remote_ranges: BTreeMap<NodeId, Vec<(SelectionOwner, SelectionRange)>>,
    pub is_forward: bool,
}

Complete selection state spanning potentially multiple DOM nodes.

This implements the W3C Selection API model with anchor/focus endpoints. The selection can span multiple IFC roots (e.g., multiple <p> elements).

Storage Model

Uses BTreeMap<NodeId, Vec<SelectionRange>> for O(log N) lookup during rendering. The key is the IFC root NodeId, and the value is every SelectionRange that IFC contributes.

Example

<p id="1">Hello [World</p>     <- Anchor in IFC 1, partial selection
<p id="2">Complete line</p>    <- InBetween, fully selected
<p id="3">Partial] end</p>     <- Focus in IFC 3, partial selection

Fields

dom_id: DomId

The DOM this selection belongs to.

anchor: SelectionAnchor

The anchor point - where the selection started (fixed during drag).

focus: SelectionFocus

The focus point - where the selection currently ends (moves during drag).

affected_nodes: BTreeMap<NodeId, Vec<SelectionRange>>

Map from IFC root NodeId to the SelectionRanges for that IFC. This allows O(log N) lookup during rendering.

Each SelectionRange contains the actual TextCursor positions for that IFC, ready to be passed to UnifiedLayout::get_selection_rects().

A node carries SEVERAL ranges when a multi-cursor session selects several occurrences in it (Ctrl+D); the ranges are disjoint and in document order.

remote_ranges: BTreeMap<NodeId, Vec<(SelectionOwner, SelectionRange)>>

OTHER PARTICIPANTS’ ranges on the same nodes, with whose they are (U1-a).

Separate from affected_nodes rather than mixed into it, because the two are painted differently and mean different things: that one is the LOCAL user’s selection and takes the node’s ::selection colour, while these take their owner’s. Mixing them made a remote participant’s range look like the local user’s own, which is worse than not showing it.

Empty for a single-user app, which is every app until one injects a remote owner.

is_forward: bool

Indicates whether anchor comes before focus in document order. True = forward selection (left-to-right), False = backward selection.

Implementations

impl TextSelection

pub fn new_collapsed( dom_id: DomId, ifc_root_node_id: NodeId, cursor: TextCursor, char_bounds: LogicalRect, mouse_position: LogicalPosition, ) -> Self

Create a new collapsed selection (cursor) at the given position.

pub fn is_collapsed(&self) -> bool

Check if this is a collapsed selection (cursor with no range).

pub fn get_range_for_node( &self, ifc_root_node_id: &NodeId, ) -> Option<&SelectionRange>

Get the FIRST selection range for a specific IFC root node. Returns None if this node is not part of the selection.

A multi-range node has more; Self::ranges_for_node returns all of them.

pub fn ranges_for_node(&self, ifc_root_node_id: &NodeId) -> &[SelectionRange]

Every range this IFC root contributes (empty slice when unaffected).

Trait Implementations

impl Clone for TextSelection

fn clone(&self) -> TextSelection

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for TextSelection

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

Formats the value using the given formatter.

impl Eq for TextSelection

impl PartialEq for TextSelection

fn eq(&self, other: &TextSelection) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for TextSelection