DampedAnimation¶

Overview¶

WARNING: PROTOTYPE, see https://github.com/phetsims/twixt/issues/3 before using! Not fully documented or stabilized. May be deleted.

Handles a single dimension of damped harmonic-oscillator motion (like a damped spring pulling towards the target).

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

Class DampedAnimation¶

import { DampedAnimation } from 'scenerystack/twixt';

Constructor¶

new DampedAnimation( providedOptions? : DampedAnimationOptions )¶

Instance Methods¶

step( dt : number )¶

Steps the animation forward in time.

Instance Properties¶

valueProperty : TProperty<number>¶

(readonly)

velocityProperty : TProperty<number>¶

(readonly)

timeElapsed¶

Type DampedAnimationOptions¶

import type { DampedAnimationOptions } from 'scenerystack/twixt';

• valueProperty?: TProperty<number>
  The current value/position.
• velocityProperty?: TProperty<number>
  The current derivative of the value
• damping?: number
  Proportion of damping applied, relative to critical damping. Thus:
• damping = 1: Critically damped (fastest approach towards the target without overshooting)
• damping < 1: Underdamped (will overshoot the target with exponentially-decaying oscillation)
• damping > 1: Overdamped (will approach with an exponential curve)
• force?: number
  Coefficient that determines the amount of force "pushing" towards the target (will be proportional to the distance from the target).
• targetValue?: number
  The target value that we are animating towards.

Source Code¶

See the source for DampedAnimation.ts in the twixt repository.