Unit-Bezier v1.0.3
Unit-Bezier
A Combination of Mozilla and Chromium implementations of Bezier Curves used for animation interpolation for Javascript
Unit-Bezier takes optimizations from both Mozilla and Chromium timing function code and combines them into performant Javascript. It is compliant with both browsers' tests.
Getting Started
Download / Clone
Install with npm:
npm install Unit-Bezier
Clone the repo using Git:
git clone --bare https://github.com/jacobcpeters/Unit-Bezier.git
Alternatively you can download this repository.
Using Unit-Bezier
Use the 'new' operator to construct a new UnitBezier object for your function/module/class. The first parameter of the constructor is an array that contains the control points for the Bezier Curve x1, y1, x2, y2. The second parameter is the epsilon that controls the desired accuracy of the estimations.
var bezier = new UnitBezier(controlPoints, epsilon);
Easing Aliases
Easy to use aliases are available for common easing types in the UnitBezier.easings object.
var bezier = new UnitBezier(UnitBezier.easings.easeInOut, 0.005);
Table of available aliases:
Easing Name | Control Points |
---|---|
linear | 0.0, 0.0, 1.0, 1.0 |
ease | 0.25, 0.1, 0.25, 1.0 |
easeIn | 0.42, 0.0, 1.0, 1.0 |
easeInOut | 0.42, 0.0, 0.58, 1.0 |
easeOut | 0.0, 0.0, 0.58, 1.0 |
easeInBack | 0.6, -0.28, 0.735, 0.045 |
easeOutBack | 0.175, 0.885, 0.32, 1.275 |
easeInOutBack | 0.680, -0.550, 0.265, 1.550 |
####Code example:
var bezier = new UnitBezier([0.0, 0.0, 1.0, 1.0], 0.000001), //linear Bezier Curve
target = document.getElementById('animated-opacity'),
animationLength = 1000, // 1000ms = 1s
startTime = Date.now();
function animateOpacity() {
var timeSinceAnimationStarted = Date.now() - startTime;
target.style.opacity = 1 * bezier.calc(timeSinceAnimationStarted / animationLength);
if(timeSinceAnimationStarted < animationLength) {
requestAnimationFrame(animateOpacity);
}
}
requestAnimationFrame(animateOpacity);
Feature requests
If Unit-Bezier doesn't support a feature you require, please put a request in the issues tracker.
License
© Jacob Peters, 2015. Licensed under an MIT license.