interpolator

A small collection of d3-ish interpolation methods.

Installation

$ npm install interpolator

Usage

Each interpolator takes two or more parameters and returns a function that tweens between the values of zero and one.

var interpolator = require('interpolator')
  , linear = interpolator.linear(0, 10)
 
linear(0)   // 0
linear(0.5) // 5
linear(1)   // 10

API

interpolator.linear(a, b)

interpolator.round(a, b)

interpolator.quad(a, b)

interpolator.cubic(a, b)

interpolator.sin(a, b)

This interpolator oscillates like a sine wave, reaching its peak at 0.5 and its trough at 0 and 1.

var sin = interpolator.sin(10, 20)
 
sin(0.00) // 10
sin(0.25) // 15
sin(0.50) // 20
sin(0.75) // 15
sin(1.00) // 10
sin(1.25) // 15
sin(1.50) // 20
sin(1.75) // 15

interpolator.bezier(a, b, ...)

Returns an n-degree Bézier curve, where n is the number of arguments.

var bezier = interpolator.bezier(0, 1, 0)
 
bezier(0.000) // 0
bezier(0.125) // 0.21875
bezier(0.250) // 0.375
bezier(0.500) // 0.5
bezier(0.750) // 0.375
bezier(0.875) // 0.21875
bezier(1.000) // 0
 
interpolator.bezier(0, 5)(0.5)          // 0.25
interpolator.bezier(0, 5, 0, 0, 0)(0.5) // 1.25