domPanZoom

Add mobile friendly panning and zooming to any HTML DOM element.

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Install

ES6

npm install --save dompanzoom

import domPanZoom from 'dompanzoom';

CDN

<script src="https://cdn.jsdelivr.net/npm/dompanzoom@v0.0.5/dist/domPanZoom.min.js"></script>

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Usage

You need two HTML DOM elements. The panZoom element within a wrapper element:

<div id="my-wrapper">
  <div id="my-container">
    <p>You can add any HTML here<p>
  </div>
</div>

Then create a new instance of domPanZoom:

new domPanZoom({
  // The ID of the wrapper element (required)
  wrapperElementID: 'my-wrapper',

  // The ID of the container element (required)
  panZoomElementID: 'my-container'
});

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Options

You can pass the following options into domPanZoom:

Option	Default
center	true	Start with a centered position. This option overrides initalPanX and initialPanY
bounds	cover	Set this option to 'contain' or 'cover' to limit the boundries of the panZoomElement to the wrapperElement. This works similar to the CSS property background-size: contain / cover. Setting this option might effect the option minZoom
minZoom	0.1	Minimum zoom, 0.5 would be half the original size
maxZoom	10	Maximum zoom, 2 would be double the original size
panStep	10	How many percent to pan by default with the panning methods panLeft, panRight, panUp and panDown
zoomStep	50	How many percent to zoom by default with the methods zoomIn and zoomOut
zoomWheelSpeed	1	The speed in which to zoom when using the mouse wheel
initialZoom	1	Initial zoom level
initialPanX	0	Initial horizontal pan in percent
initialPanY	0	Initial vertical pan in percent
transitionSpeed	400	Transition speed in milliseconds, higher values are slower

E.g.

new domPanZoom({
  wrapperElementID: 'my-wrapper',
  panZoomElementID: 'my-container',
  bounds: false,
  minZoom: 1
});

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Methods

You can use the following methods:

Getters
.getPan()	Returns an object with X and Y values of current pan position. You can pass true to get the actual pixel values, e.g. .getPan(true)
.getPanX()	Returns the current horizontal position. You can pass true to get the actual pixel values, e.g. .getPanX(true)
.getPanY()	Returns the current vertical position. You can pass true to get the actual pixel values, e.g. .getPanY(true)
.getZoom()	Returns the current zoom level

Setters
.panLeft() .panRight() .panUp() .panDown()	Pan a specific direction. You can pass a number to pan a specific amount (in percent). Pass true as first or second argument to pan instantly, e.g. .panLeft(50), .panRight(true), .panUp(30, true)
.panTo(x, y)	Pan to a specific position. The x and y values are in percent, so .panTo(50, 50) will pan to the center. Pass true as third argument to pan instantly, e.g. .panTo(50, 50, true)
.center()	Pan to centered position. Pass true to center instantly, e.g. .center(true)
.zoomIn() .zoomOut()	Zoom in and out. You can pass a number to zoom a specific amount (in percent). Pass true as first or second argument to zoom instantly, .zoomIn(20), .zoomIn(true), .zoomIn(50, true)
.zoomTo(2)	Zoom to a specific zoom level. Pass true as a second argument to zoom instantly, e.g. .zoomTo(2, true)

E.g.

var myDomPanZoom = new domPanZoom({
  wrapperElementID: 'my-wrapper',
  panZoomElementID: 'my-container'
});

myDomPanZoom.panTo(20, 80);

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Events

Event
onInit	Triggered once domPanZoom is initialized
onChange	Triggered while panning or zooming
onZoom	Triggered while zooming
onPan	Triggered while panning

E.g.

var myDomPanZoom = new domPanZoom({
  wrapperElementID: 'my-wrapper',
  panZoomElementID: 'my-container',

  onZoom: function () {
    console.log(this.getZoom());
  }
});

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Attribution

This library is heavily inspired by https://github.com/anvaka/panzoom.