Struct LayerTree 

pub struct LayerTree { /* private fields */ }

The retained-mode layer tree. Maintained across frames by the CompositorEngine.

Implementations

impl LayerTree

pub fn new() -> Self

Creates a new empty layer tree.

pub fn allocate_id(&mut self) -> LayerId

Allocates and returns a new layer ID.

pub fn insert_layer(&mut self, layer: Layer)

Inserts a new layer into the tree.

pub fn remove_layer(&mut self, id: LayerId) -> Option<Layer>

Removes a layer from the tree.

pub fn get_layer(&self, id: LayerId) -> Option<&Layer>

Returns a reference to a layer by ID.

pub fn get_layer_mut(&mut self, id: LayerId) -> Option<&mut Layer>

Returns a mutable reference to a layer by ID.

pub fn roots(&self) -> &[LayerId]

Returns the root layer IDs in painter’s order.

pub fn set_roots(&mut self, roots: Vec<LayerId>)

Sets the root layer IDs.

pub fn mark_dirty(&mut self, id: LayerId)

Marks a layer as dirty (modified since last frame).

pub fn is_dirty(&self, id: LayerId, since_generation: u64) -> bool

Returns true if the layer has been modified since the given generation.

pub fn advance_generation(&mut self)

Advances the global generation counter. Call once per frame after processing damage.

pub fn generation(&self) -> u64

Returns the current global generation.

pub fn iter_layers(&self) -> impl Iterator<Item = &Layer>

Iterates over all layers in the tree.

pub fn len(&self) -> usize

Returns the number of layers in the tree.

pub fn is_empty(&self) -> bool

Returns true if the tree has no layers.

pub fn clear(&mut self)

Clears all layers from the tree.

Trait Implementations

impl Default for LayerTree

fn default() -> Self

Returns the “default value” for a type.