smooth-state

smoothly interpolate state changes over time

var state = require('smooth-state')({ n: 0 })

setInterval(function () {
  console.log(state.get('n', Date.now()/1000))
}, 250)

setTimeout(function () {
  state.set('n', {
    value: state.limit('n')+10,
    time: 1
  })
}, 1000)

setTimeout(function () {
  state.set('n', {
    value: state.limit('n')+100,
    time: 2
  })
}, 4000)

$ node count.js 
0
0
0
2.5
5.059998035430908
7.579998970031739
10
10
10
10
10
10
10
10
10
22.5
35.0499963760376
47.60000467300415
60.10000467300415
72.65000104904175
85.19999742507935
97.7500057220459
110
110
110
110
110
110
110
110
110
110
^C

api

var smooth = require('smooth-state')

var state = smooth(values)

Create a new state object state given some initial values.

Each value can be a number or an array of numbers.

state.set(name, update)

Set the future value for the variable name:

• update.value - value to set
• update.time - duration of the transition to the future value
• update.easing - optional easing function

Values can be a number or an array of numbers.

Easing functions take a parameter t between 0 and 1 and should return values between 0 and 1. You can get easing functions from the eases package.

state.get(name, time)

Return the value of name at time.

state.limit(name)

Get the limit of the future value for name. This is the same as whichever value was last set with state.set(name).

state.tie(name)

Return a function (time) {} that returns the value for name given a time.

install

npm install smooth-state

license

BSD