README.md

PixiJS Interpolated Ticker

⚡ Unlimited render FPS – high-performance keyframe interpolation for PixiJS

🔮 Simple, drop-in API	✨ Supports PixiJS v6, v7, v8+
✅ Plugin compatible	💪 Configurable, with sensible defaults
🤏 Tiny (<2kB)	🍃 No dependencies, tree-shakeable

Sample Usage

function update() {
  spriteA.x += 10
  spriteB.rotation -= Math.PI * 0.125
}

const loop = new InterpolatedTicker({ app, update })

// run @ 24Hz:
loop.updateIntervalMs = 1000 / 24
loop.start()

Getting Started

💿 Install

npm i pixijs-interpolated-ticker

Overview

• The update() function records keyframes
• The ticker renders frames to the framebuffer using interpolated values for x, y, scale, rotation, and alpha

Advanced Configuration

Ticker Options

Configuring your interpolation ticker.

const mainLoop = new InterpolationTicker({
  app: myApplication,

  // the update loop function, used as keyframes
  update: () => {},

  // enable/disable frame interpolation (default = true)
  interpolation: true,

  // how frequently to trigger update loop (default = 1000/60)
  updateIntervalMs: 1000/30,

  // set a maximum render FPS, -1 is unlimited (default = -1)
  maxRenderFPS: 60,

  // maximum change in alpha to animate (default = 0.5):
  autoLimitAlpha: 0.1,

  // maximum change in x or y to animate (default = 100):
  autoLimitPosition: 250,

  // maximum change in rotation to animate (default = Math.PI / 4):
  autoLimitRotation: Math.PI,

  // maximum change in scale to animate (default = 1.0):
  autoLimitScale: 1.5,

  // hook triggered at the start of a render, immediately
  // following any update frames that have been processed.
  // containers' values are their latest keyframe values.
  preRender: ( deltaTimeMs ) => {},

  // hook triggered during a render, immediately before
  // writing to the framebuffer. containers' values are
  // their interpolated values.
  onRender: ( deltaTimeMs ) => {},

  // hook triggered at the end of a render. containers'
  // values are their latest keyframe values.
  postRender: ( deltaTimeMs ) => {},

  // hook triggered at the start of each evaluation cycle, before
  // any update or render frames are processed.
  evalStart: ( startTime ) => {},

  // hook triggered at the end of each evaluation cycle, after all
  // update and render frames have been processed.
  evalEnd = ( startTime ) => {},

  // initial number of containers to reserve memory in the internal
  // buffer for. note: the internal buffer will resize automatically
  // when it is full. (default = 500):
  initialCapacity: 2500,
})

and other additional non-constructor values:

const mainLoop = new InterpolatedTicker({ app })

// run the update loop at 125% speed:
mainLoop.speed = 1.25

// restrict render skips - if rendering is interrupted for any
// reason - e.g. the window loses focus - then this will
// limit the maximum number of "catch-up" frames (default = 10):
mainLoop.maxUpdatesPerRender = 10

// set custom opt-in or opt-out logic for container interpolation.
// when `container.interpolation` is not set yet, this function is
// evaluated once to hydrate that property.
//
// you could set this to () => false to opt-out by default, and then
// manually set container.interpolation = true in the containers you
// want to interpolate.
//
// (default: () => true)
mainLoop.getDefaultInterpolation = ( container ): boolean => {
  return !(container instanceof Mesh)
}

Container Options

Configuring individual containers.

Containers are granted optional properties to make it easy to configure advanced interpolation.

Interpolation is opt-out for stage containers, and disabling interpolation for a container will also disable it for all descendants.

Property	Description
interpolation	Whether interpolation is explicitly enabled or disabled for this container. The default behavior for all containers is true.
interpolatedChildren	An array of child containers to include in interpolation. When not set, children is used.
interpolationWraparound	If set, position will smoothly wraparound the given ranges.

// disable interpolation for a container
// (and all of its descendants):
const sprite = new Sprite()
sprite.interpolation = false

// allow a container's position to wraparound smoothly:
const background = new Sprite()
background.interpolationWraparound = {
  xRange: 1000,
  yRange: 2000
}

// explicitly set which children may be interpolated
const parent = new Container()
const childA = new Container()
const childB = new Container()
parent.addChild( childA, childB )
parent.interpolatedChildren = [ childB ]

Credits

PixiJS InterpolatedTicker is a spiritual successor to kittykatattack/smoothie.