Struct LayoutSnapshot 

pub struct LayoutSnapshot {
    pub nodes: HashMap<NodeId, LayoutNodeGeometry>,
    pub constraints: HashMap<NodeId, BoxConstraints>,
    pub viewport_size: LayoutSize,
}

The complete output of a layout pass.

LayoutSnapshot maps every node to its computed geometry and records the viewport size that was used. It is the primary interface between the layout engine and downstream consumers (the renderer, hit testing, accessibility).

Example

use fission_layout::{LayoutSnapshot, LayoutSize};
use fission_ir::NodeId;

let snapshot = LayoutSnapshot::new(LayoutSize::new(800.0, 600.0));
assert_eq!(snapshot.viewport_size.width, 800.0);

Fields

nodes: HashMap<NodeId, LayoutNodeGeometry>

Computed geometry for every node, keyed by NodeId.

constraints: HashMap<NodeId, BoxConstraints>

The constraints that were passed to each node during layout. Useful for debugging. Skipped during serialization.

viewport_size: LayoutSize

The viewport size used for this layout pass.

Implementations

impl LayoutSnapshot

pub fn new(viewport_size: LayoutSize) -> LayoutSnapshot

Creates an empty snapshot for the given viewport size.

pub fn get_node_geometry(&self, node_id: NodeId) -> Option<&LayoutNodeGeometry>

Returns the full geometry (rect + content size) for a node, or None if the node was not part of this layout pass.

pub fn get_node_rect(&self, node_id: NodeId) -> Option<LayoutRect>

Returns just the bounding rectangle for a node, or None if not found.

pub fn get_node_constraints(&self, node_id: NodeId) -> Option<BoxConstraints>

Returns the constraints that were passed to a node during layout, or None if not found. Useful for debugging layout issues.

Trait Implementations

impl Clone for LayoutSnapshot

fn clone(&self) -> LayoutSnapshot

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for LayoutSnapshot

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

Formats the value using the given formatter.

impl Default for LayoutSnapshot

fn default() -> LayoutSnapshot

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for LayoutSnapshot

fn deserialize<__D>( __deserializer: __D, ) -> Result<LayoutSnapshot, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for LayoutSnapshot

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for LayoutSnapshot

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for LayoutSnapshot