easing-coordinates

Easing Coordinates

Usage

The easingCoordinates function takes steps and cubic-bezier single-transition-timing-functions as input and returns an array of "low-poly" xy-coordinates.

import { easingCoordinates } from 'easing-coordinates'

easingCoordinates('cubic-bezier(0.5, 0, 0.5, 1)')
/* =>
[
  { x: 0, y: 0 },
  { x: 0.099, y: 0.0143172435 },
  { x: 0.189, y: 0.0569704145 },
  { x: 0.265, y: 0.1207430791 },
  { x: 0.329, y: 0.1976360165 },
  { x: 0.384, y: 0.281541323 },
  { x: 0.433, y: 0.3687643431 },
  { x: 0.479, y: 0.4580875338 },
  { x: 0.524, y: 0.547869462 },
  { x: 0.57, y: 0.6368561714 },
  { x: 0.619, y: 0.7234436574 },
  { x: 0.674, y: 0.8064697166 },
  { x: 0.738, y: 0.8823204807 },
  { x: 0.815, y: 0.9456314885 },
  { x: 0.906, y: 0.9871537401 },
  { x: 1, y: 1 },
]
*/

easingCoordinates('steps(4)')
/* =>
[
  { x: 0, y: 0 },
  { x: 0.25, y: 0 },
  { x: 0.25, y: 0.25 },
  { x: 0.5, y: 0.25 },
  { x: 0.5, y: 0.5 },
  { x: 0.75, y: 0.5 },
  { x: 0.75, y: 0.75 },
  { x: 1, y: 0.75 },
]
*/

Use stepsCoordinates and cubicCoordinates methods directly depending on your data:

import { cubicCoordinates, easingCoordinates, stepsCoordinates } from './index'

easingCoordinates('cubic-bezier(0.42, 0, 0.58, 1)') ==
  cubicCoordinates(0.42, 0, 0.58, 1)
easingCoordinates('steps(4, skip-end)') == stepsCoordinates(4, 'skip-end')

Increase hypotSize (default = 0.1) to get a "lower-poly" version of your cubic-bezier functions and make sure incrementSize is always smaller than hypotSize.

interface ICoordinate {
  x: number
  y: number
}
function easingCoordinates(
  easingFunction: string,
  hypotSize?: number,
  incrementSize?: number
): ICoordinate[]
function stepsCoordinates(steps: number, skip = 'skip-end'): ICoordinate[]
function cubicCoordinates(
  x1: number,
  y1: number,
  x2: number,
  y2: number,
  hypotSize = 0.1,
  incrementSize = 0.001
): ICoordinate[]

Build

(See package.json for more scripts)

# Checkout and then
npm install

# Compile and watch the .ts files
npm run watch

# Run test
npm run test