0fb859dc fixed mobile overflwo options [كارل مبارك]
bezier-easing [](https://travis-ci.org/gre/bezier-easing)
===
BezierEasing provides **Cubic Bezier** Curve easing which generalizes easing functions (ease-in, ease-out, ease-in-out, ...any other custom curve) exactly like in CSS Transitions.
Implementing efficient lookup is not easy because it implies projecting
the X coordinate to a Bezier Curve.
This micro library uses fast heuristics (involving dichotomic search, newton-raphson, sampling) to focus on **performance** and **precision**.
> It is heavily based on implementations available in Firefox and Chrome (for the CSS transition-timing-function property).
Usage
-------
```javascript
var easing = BezierEasing(0, 0, 1, 0.5);
// easing allows to project x in [0.0,1.0] range onto the bezier-curve defined by the 4 points (see schema below).
console.log(easing(0.0)); // 0.0
console.log(easing(0.5)); // 0.3125
console.log(easing(1.0)); // 1.0
```
(this schema is from the CSS spec)
[](http://www.w3.org/TR/css3-transitions/#transition-timing-function-property)
> `BezierEasing(P1.x, P1.y, P2.x, P2.y)`
Install
-------
[](http://npmjs.org/package/bezier-easing)
It is the equivalent to [CSS Transitions' `transition-timing-function`](http://www.w3.org/TR/css3-transitions/#transition-timing-function-property).
In the same way you can define in CSS `cubic-bezier(0.42, 0, 0.58, 1)`,
with BezierEasing, you can define it using `BezierEasing(0.42, 0, 0.58, 1)` which have the `` function taking an X and computing the Y interpolated easing value (see schema).
License
-------
MIT License.
Tests
---
[](https://travis-ci.org/gre/bezier-easing)
```
npm test
```
See also
===
- [https://github.com/gre/bezier-easing-editor/](https://github.com/gre/bezier-easing-editor/)
Who use it?
===
- [React Native](https://github.com/facebook/react-native/blob/master/Libraries/Animated/src/bezier.js)
- [Apple®](http://images.apple.com/v/mac-pro/home/b/scripts/overview.js) :)
- [Velocity.js](https://github.com/julianshapiro/velocity)
- [GLSL.io](http://glsl.io/) and [Diaporama Maker](https://github.com/gre/diaporama-maker)
- [ipo](https://github.com/gre/ipo)
More informations
-----------------
Implementation based on this [article](http://greweb.me/2012/02/bezier-curve-based-easing-functions-from-concept-to-implementation/).
Contributing
------------
You need a `node` installed.
Install the deps:
```
npm install
```
The library is in `index.js`.
Ensure any modication will:
- keep validating the tests (run `npm test`)
- not bring performance regression (compare with `npm run benchmark` – don't rely 100% on its precision but it still helps to notice big gaps)
- Run the visual example: `npm run visual`