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    bezier-easing
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    2.1.0 • Public • Published

    bezier-easing Build Status

    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

    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)

    TimingFunction.png

    BezierEasing(P1.x, P1.y, P2.x, P2.y)

    Install

    npm install bezier-easing

    It is the equivalent to CSS Transitions' transition-timing-function.

    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

    Build Status

    npm test
    

    See also

    Who use it?

    More informations

    Implementation based on this article.

    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

    Install

    npm i bezier-easing

    DownloadsWeekly Downloads

    225,399

    Version

    2.1.0

    License

    MIT

    Unpacked Size

    14.9 kB

    Total Files

    10

    Last publish

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