Spring

import { Spring } from 'pixi-silk';

Damped harmonic spring with unit mass, integrated in fixed 1/240 s sub-steps. stiffness and damping follow the usual UI spring convention. The defaults are 170 and 26.

Constructors#

Constructor#

new Spring(
   value?: number, 
   stiffness?: number, 
   damping?: number
): Spring;

Starts at rest at value, with its target there too.

Parameters#

Parameter	Type	Default value
`value`	`number`	`0`
`stiffness`	`number`	`170`
`damping`	`number`	`26`

Returns#

Spring

Properties#

Property	Type	Default value	Description	Defined in
`damping`	`number`	`undefined`	Friction. Lower bounces more. Default 26.	motion.ts:38
`stiffness`	`number`	`undefined`	Pull towards the target. Higher is faster. Default 170.	motion.ts:36
`target`	`number`	`undefined`	Value the spring moves towards.	motion.ts:32
`value`	`number`	`undefined`	Current value.	motion.ts:30
`velocity`	`number`	`0`	Current speed, in units per second.	motion.ts:34

Accessors#

settled#

Get Signature#

get settled(): boolean;

True once the spring is within 1e-4 of its target and its speed is below 1e-4.

Returns

boolean

Methods#

step()#

step(dtSeconds: number): number;

Advances the spring by dtSeconds, capped at 0.1 s so a stalled tab does not jump, and returns the new value.

Parameters#

Parameter	Type
`dtSeconds`	`number`

Returns#

number