Fittability¶

Overview¶

A sub-component of an Instance that handles matters relating to whether fitted blocks should not fit if possible. We mostly mark our own drawables as fittable, and track whether our subtree is all fittable (so that common-ancestor fits can determine if their bounds will change).

@author Jonathan Olson <jonathan.olson@colorado.edu>

Class Fittability¶

import { Fittability } from 'scenerystack/scenery';

Constructor¶

new Fittability( instance )¶

Instance Methods¶

initialize( display, trail )¶

Responsible for initialization and cleaning of this. If the parameters are both null, we'll want to clean our external references (like Instance does). @public

@param {Display|null} display @param {Trail|null} trail @returns {Fittability} - Returns this, to allow chaining.

checkSelfFittability()¶

Called when the instance is updating its rendering state (as any fittability changes to existing instances will trigger an update there). @public

isSelfFitSupported()¶

Whether our node's performance flags allows the subtree to be fitted. @private

Any updates to flags (for instance, a 'dynamic' flag perhaps?) should be added here.

@returns {boolean}

markSubtreeFittable()¶

Called when our parent just became fittable. Responsible for flagging subtrees with the ancestorsFittable flag, up to the point where they are fittable. @private

markSubtreeUnfittable()¶

Called when our parent just became unfittable and we are fittable. Responsible for flagging subtrees with the !ancestorsFittable flag, up to the point where they are unfittable. @private

updateSelfFittable()¶

Called when our Node's self fit-ability has changed. @private

incrementSubtreeUnfittableCount()¶

A child instance's subtree became unfittable, OR our 'self' became unfittable. This is responsible for updating the subtreeFittableCount for this instance AND up to all ancestors that would be affected by the change. @private

decrementSubtreeUnfittableCount()¶

A child instance's subtree became fittable, OR our 'self' became fittable. This is responsible for updating the subtreeFittableCount for this instance AND up to all ancestors that would be affected by the change. @private

onInsert( childFittability )¶

Called when an instance is added as a child to our instance. Updates necessary counts. @public

@param {Fittability} childFittability - The Fittability of the new child instance.

onRemove( childFittability )¶

Called when a child instance is removed from our instance. Updates necessary counts. @public

@param {Fittability} childFittability - The Fittability of the old child instance.

audit()¶

Sanity checks that run when slow assertions are enabled. Enforces the invariants of the Fittability subsystem. @public

Source Code¶

See the source for Fittability.js in the scenery repository.