/zoom

Javascript library to do pinch zoom that preserves scale and rotation correctly.

Primary LanguageJavaScriptMIT LicenseMIT

Zoom it!

Allows your users to zoom, rotate, and pan images using touch gestures.

For a DEMO open this on mobile: http://anitasv.github.io/zoom/

Type Link Size
Minified http://anitasv.github.io/zoom/zoom-1.0.7.min.js 2472 bytes (gzip: 1155 bytes)
Debugging http://anitasv.github.io/zoom/zoom-1.0.7.js 12893 bytes
NPM https://www.npmjs.com/package/zoom-it

For an explanation of math see https://github.com/anitasv/zoom/wiki/Explaining-Math

Send pull requests, bug reports, and feature requests to https://github.com/anitasv/zoom/

Usage

<div width=320 height=240 style="overflow:hidden;">
    <!-- this doesn't have to be an image -->
    <img id="torotate" width=320 height=240 src="https://lh3.googleusercontent.com/w33i78Rt0j4GHr7SA1luYtBAtmC1DmRHwobUcK1wCKivA_u4VczsDw0CweLmJpUwFRUs=w1920-h1200-no">
</div>

<script type="text/javascript" src="http://anitasv.github.io/zoom/zoom-1.0.7.min.js"> </script>

The overflow:hidden is to crop the image moving outside the original border. Be creative. Hotlinking to github.io may get you blocked; so copy to your own location.

var elem = document.getElementById('torotate');
var zm = new Zoom(elem, {
    rotate: true
});

// after use, call to remove event listeners, etc:
zm.destroy()

Pan cannot be currently disabled, there is an outstanding issue on it.

You can do operations like zm.reset() on this object, by default it attaches listeners to the object given.

Optionally pass a window-like object as the third parameter (e.g. for testing, or use in a non-browser environment).

If you are using NPM, then

var zoom = require("zoom-it");

var elem = document.getElementById('torotate');
var zm = new zoom.Zoom(elem, {
    rotate: true,
    minZoom: 0,
    maxZoom: Infinity,
    pan: false,
});