create-transition
v0.4.1
Published
Create transitions that CSS can't.
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create-transition
Create transition animations that CSS can't.
Demo
https://jiangfengming.github.io/create-transition/examples/
Usage
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>create-transition</title>
<meta name="viewport" content="width=device-width, initial-scale=1">
<style>
body {
height: 9999px;
background-image: linear-gradient(to bottom, rgba(255,255,0,0.5), rgba(0,0,255,0.5));
}
.fixed {
position: fixed;
top: 10px;
left: 10px;
}
.box {
margin-top: 2000px;
width: 200px;
height: 200px;
background: #FF2F92;
}
</style>
</head>
<body>
<div class="fixed">
<p><input type="text" id="num" value="0"></p>
<button id="scrollToTop">scroll to top</button>
<button id="scrollToBottom">scroll to bottom</button>
<button id="scrollToBox">scroll to box</button>
<button id="inc">increase</button>
<button id="dec">decrease</button>
</div>
<div class="box"></div>
<script type="module">
import { createTransition, easeInOutQuad, easeInOutCubic } from 'https://unpkg.com/create-transition'
document.getElementById('scrollToTop').addEventListener('click', scrollToTop)
document.getElementById('scrollToBottom').addEventListener('click', scrollToBottom)
document.getElementById('scrollToBox').addEventListener('click', () =>
scrollToElement(document.querySelector('.box'), 150)
)
document.getElementById('inc').addEventListener('click', inc)
document.getElementById('dec').addEventListener('click', dec)
function scrollToElement(el, offset = 0) {
const y = window.scrollY
const d = el.getBoundingClientRect().top - offset
createTransition(t => window.scrollTo(0, y + t * d), 300, easeInOutQuad)
}
function scrollToTop() {
const y = window.scrollY
createTransition(t => window.scrollTo(0, y - t * y), 300, easeInOutQuad)
}
function scrollToBottom() {
const y = window.scrollY
const d = document.documentElement.scrollHeight - window.innerHeight - window.scrollY
createTransition(t => window.scrollTo(0, y + t * d), 300, easeInOutQuad)
}
function inc() {
const num = document.getElementById('num')
const n = parseInt(num.value) || 0
createTransition(t => num.value = n + Math.round(100 * t), 2000, easeInOutCubic)
}
function dec() {
const num = document.getElementById('num')
const n = parseInt(num.value) || 0
createTransition(t => num.value = n - Math.round(100 * t), 2000, easeInOutCubic)
}
</script>
</body>
</html>
Import
import { createTransition, easeInOutQuad /* , ...other easing functions */} from 'create-transition'
If you don't need easing functions:
import createTransition from 'create-transition'
APIs
createTransition(animate, duration, easing = linear)
Creates a transition between two states. It uses requestAnimationFrame underneath.
Params:
animate(o)
Function. The animation function to run per frame. o
is the eased value computed by easing(t)
.
duration
Number. The number of milliseconds a transition animation should take to complete.
easing(t)
Function. A mathematical function that describes how fast one-dimensional values change during animations.
This lets you vary the animation's speed over the course of its duration. See more about easing functions:
<timing-function>
and
Improved Easing Functions
t
: Number. t = (currentTime - startTime) / duration
. It represents the percentage of completeness of the transition.
It's value is between 0 and 1.
The return value is the eased value of t
. 0.0
represents the initial state, and 1.0
represents the final state.
Depending on the specific function used, the calculated output can sometimes grow to be greater than 1.0 or smaller
than 0.0 during the course of an animation. This causes the animation to go farther than the final state, and then
return. For some properties, such as left or right, this creates a kind of "bouncing" effect.
Example easing function:
function easeInQuad(t) {
return t * t
}
You can create easing functions using bezier-easing.
generateEaseInBack(amount)
Generates an easeInBack function with custom amount
.
generateEaseOutBack(amount)
Generates an easeOutBack function with custom amount
.
generateEaseInOutBack(amount)
Generates an easeInOutBack function with custom amount
.
generateEaseInElastic(amplitude, period)
Generates an easeInElastic function with custom amplitude
and period
.
generateEaseOutElastic(amplitude, period)
Generates an easeOutElastic function with custom amplitude
and period
.
generateEaseInOutElastic(amplitude, period)
Generates an easeInOutElastic function with custom amplitude
and period
.
Preset easing functions
- linear
- easeInQuad
- easeOutQuad
- easeInOutQuad
- easeInCubic
- easeOutCubic
- easeInOutCubic
- easeInQuart
- easeOutQuart
- easeInOutQuart
- easeInQuint
- easeOutQuint
- easeInOutQuint
- easeInSine
- easeOutSine
- easeInOutSine
- easeInBack (shortcut of
generateEaseInBack(1.7)
) - easeOutBack (shortcut of
generateEaseOutBack(1.7)
) - easeInOutBack (shortcut of
generateEaseInOutBack(1.7 * 1.525)
) - easeInElastic (shortcut of
generateEaseInElastic(1, 0.3)
) - easeOutElastic (shortcut of
generateEaseOutElastic(1, 0.3)
) - easeInOutElastic (shortcut of
generateEaseInOutElastic(1, 0.3 * 1.5)
) - easeInBounce
- easeOutBounce
- easeInOutBounce
Easing functions are collected from:
- https://gist.github.com/gre/1650294#gistcomment-1806616
- https://github.com/CharlotteGore/functional-easing/blob/master/penner-easing.js
- https://github.com/yuichiroharai/easeplus-velocity/blob/master/release/1.2/velocity.easeplus.js
- https://github.com/CreateJS/TweenJS/blob/master/src/tweenjs/Ease.js