Struct SceneModel 

pub struct SceneModel(/* private fields */);

A shared, cloneable handle to a Scene.

Implementations

impl SceneModel

pub fn new() -> Self

A handle to a fresh empty scene with the default spatial index.

pub fn with_index(index: Box<dyn SpatialIndex>) -> Self

A handle to a fresh scene with a custom SpatialIndex.

pub fn from_scene(scene: Scene) -> Self

Wrap an existing Scene in a handle. Used by SceneView::new for the single-view path.

pub fn handle_count(&self) -> usize

Number of distinct handles to this scene (1 = unshared).

pub fn add_widget<W: Widget + 'static>(&self, widget: W, rect: Rect) -> ItemId

Single-view heavyweight widget (the one-shot Once path). The first view to build drains it; a second view sharing this model produces no child for it. For multi-view, use add_widget_item.

pub fn add_widget_item<P: 'static>(&self, payload: P, rect: Rect) -> ItemId

Multi-view heavyweight item: store a typed payload; each view builds its own widget instance from it via its delegate. Returns the ItemId.

pub fn set_payload<P: 'static>(&self, id: ItemId, payload: P)

Replace the payload of a Delegated heavyweight item; every view rebuilds that item’s widget on the next pass.

Panics

Panics if id is unknown, refers to a single-view add_widget (Once) entry, or refers to a lightweight item.

pub fn payload(&self, id: ItemId) -> Option<Rc<dyn Any>>

The current type-erased payload of a Delegated item, if any.

pub fn add_item<I: SceneItem + 'static>( &self, item: I, local_pos: Point, ) -> ItemId

Add a lightweight SceneItem at local_pos.

pub fn add_item_dynamic<I: SceneItem + 'static>( &self, item: I, local_pos: Point, ) -> ItemId

Add a lightweight item with signal-driven (dynamic) bounds.

pub fn add_boxed_item( &self, item: Box<dyn SceneItem>, local_pos: Point, ) -> ItemId

Add an already-boxed lightweight item at local_pos. The boxed-dyn counterpart of add_item, used by SceneListAdapter.

pub fn set_local_pos(&self, id: ItemId, local_pos: Point)

Move id to local_pos in its parent’s coordinate space; notifies all views.

pub fn set_local_bounds(&self, id: ItemId, local_bounds: Rect)

Replace the local bounding rect of id; notifies all views.

pub fn set_transform(&self, id: ItemId, transform: Transform2D)

Set an additional local-to-parent transform (rotation, scale) on id; notifies all views.

pub fn set_flags(&self, id: ItemId, flags: ItemFlags)

Replace the complete ItemFlags bitset for id; notifies all views.

pub fn set_flag(&self, id: ItemId, flag: ItemFlags, on: bool)

Set or clear a single ItemFlags bit on id; notifies all views.

pub fn set_visible(&self, id: ItemId, visible: bool)

Show or hide id (also hides its descendants); notifies all views.

pub fn set_opacity(&self, id: ItemId, opacity: f32)

Set the paint opacity of id (0.0 = transparent, 1.0 = opaque); notifies all views.

pub fn set_item_fill(&self, id: ItemId, fill: impl Into<ColorProp>)

Replace a lightweight item’s fill colour live; every view repaints (no relayout/rebuild). Accepts a plain Color, a theme role, a Signal<Color>, or a Signal<Role>. See Scene::set_item_fill for the reactive-colour contract.

pub fn clear_item_fill(&self, id: ItemId)

Clear a lightweight item’s fill; every view repaints.

pub fn set_item_stroke( &self, id: ItemId, color: impl Into<ColorProp>, style: StrokeStyle, )

Replace a lightweight item’s stroke (colour + [StrokeStyle]) live; every view repaints (no relayout/rebuild).

pub fn clear_item_stroke(&self, id: ItemId)

Clear a lightweight item’s stroke; every view repaints.

pub fn set_z(&self, id: ItemId, z: f32)

Set the z-order of id within its layer; higher values paint on top.

pub fn bring_to_front(&self, id: ItemId)

Give id the highest z-value in its layer so it paints on top of all siblings.

pub fn send_to_back(&self, id: ItemId)

Give id the lowest z-value in its layer so it paints beneath all siblings.

pub fn set_layer(&self, id: ItemId, layer: SceneLayer)

Move id to a different SceneLayer (background, default, foreground); notifies all views.

pub fn set_item_parent(&self, child: ItemId, parent: Option<ItemId>)

Re-parent child under parent (or under the scene root when None); notifies all views.

pub fn remove(&self, id: ItemId)

Remove an item and its descendants. Drops any Delegated payload Rc and cleans the item’s a11y mappings; alive logical children re-root.

pub fn orphan(&self, id: ItemId)

Promote an item’s children to the scene root.

pub fn set_item_handlers( &self, id: ItemId, handlers: Option<SceneItemHandlerSet>, )

Replace the SceneItemHandlerSet of id, or clear it with None.

pub fn with_handlers_mut<R>( &self, id: ItemId, f: impl FnOnce(&mut SceneItemHandlerSet) -> R, ) -> Option<R>

Mutate an item’s handler set through a closure (avoids returning a borrow guard tied to the RefMut).

pub fn add_magnet(&self, item: ItemId, magnet: Magnet) -> MagnetId

Attach a Magnet to item; see Scene::add_magnet.

pub fn remove_magnet(&self, magnet: MagnetId)

Remove a magnet by id; see Scene::remove_magnet.

pub fn clear_magnets(&self, item: ItemId)

Remove every magnet on item; see Scene::clear_magnets.

pub fn set_magnet_local_pos(&self, magnet: MagnetId, local_pos: Point)

Move a magnet in its item’s local frame; see Scene::set_magnet_local_pos.

pub fn set_magnet_enabled(&self, magnet: MagnetId, enabled: bool)

Enable or disable a magnet; see Scene::set_magnet_enabled.

pub fn magnet_ids_of(&self, item: ItemId) -> Vec<MagnetId>

Ids of every magnet on item; see Scene::magnet_ids_of.

pub fn magnet_owner(&self, magnet: MagnetId) -> Option<ItemId>

The owning item of a magnet; see Scene::magnet_owner.

pub fn magnet_scene_pos(&self, magnet: MagnetId) -> Option<Point>

A magnet’s scene position; see Scene::magnet_scene_pos.

pub fn magnet(&self, magnet: MagnetId) -> Option<MagnetRef>

Resolve a magnet to a MagnetRef snapshot; see Scene::magnet.

pub fn compute_item_snap( &self, dragged: ItemId, drag_delta: Vec2, capture_radius: f32, predicate: &dyn Fn(&MagnetRef, &MagnetRef) -> MagnetVerdict, ) -> Option<MagnetSnap>

Best item-drag snap; see Scene::compute_item_snap. A shared (read-only) borrow is held while the predicate runs over owned candidate snapshots, so the predicate may read but must not mutate the model.

pub fn compute_port_snap( &self, source: MagnetId, cursor_scene: Point, capture_radius: f32, predicate: &dyn Fn(&MagnetRef, &MagnetRef) -> MagnetVerdict, ) -> Option<(MagnetRef, Option<Rc<dyn Any>>)>

Best port-drag snap; see Scene::compute_port_snap.

pub fn nearest_magnet(&self, scene_pt: Point, radius: f32) -> Option<MagnetId>

Nearest enabled magnet within radius; see Scene::nearest_magnet.

pub fn set_scene_rect(&self, rect: Option<Rect>)

Set the logical extent of the scene (used for scroll-bar sizing); None = unbounded.

pub fn pan_axes(&self, axes: PanAxes)

Restrict panning to horizontal, vertical, or both axes; updates pan_axes_signal.

pub fn zoomable(&self, on: bool)

Enable or disable pinch/scroll zoom; updates zoomable_signal.

pub fn set_pan_bounds(&self, bounds: Option<Rect>)

Clamp the camera pan to bounds (scene coordinates); None = no limit; updates pan_bounds_signal.

pub fn set_zoom_range(&self, range: Option<RangeInclusive<f32>>)

Restrict the zoom factor to range; None = no limit; updates zoom_range_signal.

pub fn add_a11y_group(&self, builder: A11yGroupBuilder) -> A11yGroupId

Register a logical AT group (landmark / rotor category container); returns its stable A11yGroupId.

pub fn remove_a11y_group(&self, id: A11yGroupId)

Remove a previously registered AT group; triggers an a11y_change_signal bump.

pub fn set_a11y_parent(&self, child: A11yNode, parent: Option<A11yNode>)

Re-parent child in the AT tree, overriding the default visual parent; None re-attaches under the scene root.

pub fn add_a11y_relation( &self, from: A11yNode, kind: A11yRelation, to: A11yNode, )

Declare a cross-node AT relationship (controls, describes, labels) from from to to.

pub fn set_a11y_live(&self, node: A11yNode, live: Live)

Mark node as a live region (Polite or Assertive) so assistive tech announces changes to it.

pub fn set_a11y_landmark(&self, node: A11yNode, role: Role)

Assign a landmark role to node (e.g. Role::Region, Role::Main) for rotor navigation.

pub fn set_a11y_categories(&self, node: A11yNode, categories: &[A11yCategory])

Register node under the given rotor A11yCategory slices so it appears in category-filtered navigation.

pub fn refresh_dynamic_bounds(&self) -> bool

Re-read signal-driven bounds for add_item_dynamic entries; returns true if any changed.

pub fn item_change_signal(&self) -> Signal<ItemChange>

Reactive signal fired on every structural scene change; all views observe this to reconcile.

pub fn a11y_change_signal(&self) -> Signal<u64>

Reactive monotonic counter bumped on every AT-structure change; views re-walk accessibility on any increment.

pub fn mutation_version(&self) -> u64

Monotonic counter incremented on every mutation; useful for cache invalidation without observing a signal.

pub fn pan_axes_signal(&self) -> Signal<PanAxes>

Reactive current PanAxes restriction; updated by pan_axes.

pub fn pan_bounds_signal(&self) -> Signal<Option<Rect>>

Reactive camera-pan clamp bounds; updated by set_pan_bounds.

pub fn zoom_range_signal(&self) -> Signal<Option<RangeInclusive<f32>>>

Reactive zoom-factor clamp range; updated by set_zoom_range.

pub fn zoomable_signal(&self) -> Signal<bool>

Reactive zoom-enabled flag; updated by zoomable.

pub fn len(&self) -> usize

Total number of items in the scene (lightweight + heavyweight).

pub fn is_empty(&self) -> bool

Returns true when the scene contains no items.

pub fn ids(&self) -> Vec<ItemId>

All ItemIds currently in the scene, in insertion order.

pub fn local_pos(&self, id: ItemId) -> Option<Point>

The local position of id in its parent’s coordinate space; None if id is unknown.

pub fn local_bounds(&self, id: ItemId) -> Option<Rect>

The local bounding rect of id; None if id is unknown.

pub fn transform(&self, id: ItemId) -> Option<Transform2D>

The additional local-to-parent transform of id (beyond position); None if none is set.

pub fn scene_transform(&self, id: ItemId) -> Transform2D

The full local-to-scene transform for id (parent chain composed); identity if id is unknown.

pub fn scene_pos(&self, id: ItemId) -> Option<Point>

The origin of id mapped into scene coordinates; None if id is unknown.

pub fn scene_rect(&self, id: ItemId) -> Option<Rect>

The bounding rect of id in scene coordinates (local bounds transformed by the parent chain); None if unknown.

pub fn flags(&self, id: ItemId) -> Option<ItemFlags>

The ItemFlags bitset of id; None if id is unknown.

pub fn is_effectively_visible(&self, id: ItemId) -> bool

Returns true if id and all of its ancestors are visible.

pub fn opacity(&self, id: ItemId) -> Option<f32>

The own opacity of id (ignoring ancestors); None if id is unknown.

pub fn effective_opacity(&self, id: ItemId) -> f32

Accumulated opacity for id (own × each ancestor’s opacity).

pub fn z(&self, id: ItemId) -> Option<f32>

The z-order value of id within its layer; None if id is unknown.

pub fn layer(&self, id: ItemId) -> Option<SceneLayer>

The SceneLayer of id; None if id is unknown.

pub fn parent_of(&self, id: ItemId) -> Option<ItemId>

The direct parent of id, or None if it is a root item (or unknown).

pub fn is_descendant_of(&self, id: ItemId, ancestor: ItemId) -> bool

Returns true if id is anywhere in ancestor’s subtree.

pub fn scene_rect_extent(&self) -> Option<Rect>

The logical extent set via set_scene_rect; None = unbounded.

pub fn current_pan_axes(&self) -> PanAxes

The current pan-axis restriction without subscribing to its signal.

pub fn is_zoomable(&self) -> bool

Returns true if zoom is currently enabled (snapshot; use zoomable_signal for reactivity).

pub fn current_pan_bounds(&self) -> Option<Rect>

Current pan-clamp bounds without subscribing to its signal.

pub fn current_zoom_range(&self) -> Option<RangeInclusive<f32>>

Current zoom-factor clamp range without subscribing to its signal.

pub fn items_in_rect(&self, scene_rect: Rect) -> Vec<ItemId>

All items whose bounding rects overlap scene_rect (spatial-index query).

pub fn item_at(&self, scene_pt: Point) -> Option<ItemId>

The topmost item under scene_pt using exact-shape hit-testing; None if no item is hit.

pub fn items_at(&self, scene_pt: Point) -> Vec<ItemId>

All items under scene_pt (exact-shape hit-test), ordered front-to-back.

pub fn colliding_items(&self, id: ItemId) -> Vec<ItemId>

All items whose bounding rects intersect id’s bounding rect.

pub fn a11y_parent_of(&self, child: A11yNode) -> Option<A11yNode>

The AT-tree parent of child as set by set_a11y_parent; None = visual default.

Trait Implementations

impl Clone for SceneModel

fn clone(&self) -> Self

Produce a second handle to the same scene (cheap Rc clone).

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

Performs copy-assignment from source.

impl Debug for SceneModel

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

Formats the value using the given formatter.

impl Default for SceneModel

fn default() -> Self

Returns the “default value” for a type.