tcd-jarallax

Just Another Parallax

Smooth parallax scrolling effect for background images, videos and inline elements. Code in pure JavaScript with NO dependencies + jQuery supported. YouTube, Vimeo and Local Videos parallax supported.

Demo

Tested Browsers

• Latest browsers on Mac and Windows (Chrome, Firefox, Safari, IE11, Edge)
• Latest Chrome on Android
• Latest Safari on iOs

Want WordPress Plugin?

We made WordPress plugin to easily make backgrounds for content in your blog with all Jarallax features.

Demo: https://wp.nkdev.info/free-advanced-wordpress-backgrounds/

Download: https://nkdev.info/downloads/advanced-wordpress-backgrounds/

Getting Started

ES6

npm install jarallax --save

import {
    jarallax,
    jarallaxElement,
    jarallaxVideo
} from 'jarallax';
 
jarallaxVideo();
jarallaxElement();

Note: in this way is not available jQuery and data-attribute automatic initialization. Use javascript call instead (Example).

Browser

<!-- Jarallax -->
<script src="jarallax/dist/jarallax.min.js"></script>
 
<!-- Include it if you want to use Video parallax -->
<script src="jarallax/dist/jarallax-video.min.js"></script>
 
<!-- Include it if you want to parallax any element -->
<script src="jarallax/dist/jarallax-element.min.js"></script>

CDN

Link directly from unpkg

<!-- Jarallax -->
<script src="https://unpkg.com/jarallax@1.10/dist/jarallax.min.js"></script>
 
<!-- Include it if you want to use Video parallax -->
<script src="https://unpkg.com/jarallax@1.10/dist/jarallax-video.min.js"></script>
 
<!-- Include it if you want to parallax any element -->
<script src="https://unpkg.com/jarallax@1.10/dist/jarallax-element.min.js"></script>

Supported plugins

You can add these plugins before jarallax initialize.

• object-fit-images polyfill for object-fit styles;
• lazysizes lazy-load images with srcset support;
• resize-observer-polyfill resize observer polyfill for automaticResize option;

Set up your HTML

<!-- Background Image Parallax -->
<div class="jarallax">
    <img class="jarallax-img" src="<background_image_url_here>" alt="">
    Your content here...
</div>
 
<!-- Background Image Parallax with <picture> tag -->
<div class="jarallax">
    <picture class="jarallax-img">
        <source media="..." srcset="<alternative_background_image_url_here>">
        <img src="<background_image_url_here>" alt="">
    </picture>
    Your content here...
</div>
 
<!-- Alternate: Background Image Parallax -->
<div class="jarallax" style="background-image: url('<background_image_url_here>');">
    Your content here...
</div>

Additional styles

These styles need to correct background image position before Jarallax initialized:

.jarallax {
    position: relative;
    z-index: 0;
}
.jarallax > .jarallax-img {
    position: absolute;
    object-fit: cover;
    /* support for plugin https://github.com/bfred-it/object-fit-images */
    font-family: 'object-fit: cover;';
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
}

You can include it from dist/jarallax.css.

Call the plugin

A. Data attribute way

<div data-jarallax data-speed="0.2" class="jarallax">
    <img class="jarallax-img" src="<background_image_url_here>" alt="">
    Your content here...
</div>

Note: You can use all available options as data attributes. For example: data-speed, data-img-src, data-img-size, etc...

B. JavaScript way

jarallax(document.querySelectorAll('.jarallax'), {
    speed: 0.2
});

C. jQuery way

$('.jarallax').jarallax({
    speed: 0.2
});

Background Video Usage Examples

<!-- Background YouTube Parallax -->
<div class="jarallax" data-jarallax-video="https://www.youtube.com/watch?v=ab0TSkLe-E0">
    Your content here...
</div>
 
<!-- Background Vimeo Parallax -->
<div class="jarallax" data-jarallax-video="https://vimeo.com/110138539">
    Your content here...
</div>
 
<!-- Background Local Video Parallax -->
<div class="jarallax" data-jarallax-video="mp4:./video/local-video.mp4,webm:./video/local-video.webm,ogv:./video/local-video.ogv">
    Your content here...
</div>

Note: for local videos required only 1 video type, not necessary use all mp4, webm and ogv. This need only for maximum compatibility with all browsers.

Any Element Parallax Usage Examples

<!-- Element will be parallaxed on -140 pixels from the screen center by Y axis -->
<div data-jarallax-element="-140">
    Your content here...
</div>
 
<!-- Element will be parallaxed on 250 pixels from the screen center by Y axis and on -100 pixels from the screen center by X axis -->
<div data-jarallax-element="250 -100">
    Your content here...
</div>

Note: this is more like experimental feature, so the behavior could be changed in the future releases.

Options

Options can be passed in data attributes or in object when you initialize jarallax from script.

Name	Type	Default	Description
type	string	scroll	scroll, scale, opacity, scroll-opacity, scale-opacity.
speed	float	0.5	Parallax effect speed. Provide numbers from -1.0 to 2.0.
imgSrc	path	null	Image url. By default used image from background.
imgElement	dom / selector	.jarallax-img	Image tag that will be used as background.
imgSize	string	cover	Image size. If you use <img> tag for background, you should add object-fit values, else use background-size values.
imgPosition	string	50% 50%	Image position. If you use <img> tag for background, you should add object-position values, else use background-position values.
imgRepeat	string	no-repeat	Image repeat. Supported only background-position values.
keepImg	boolean	false	Keep <img> tag in it's default place after Jarallax inited.
elementInViewport	dom	null	Use custom DOM / jQuery element to check if parallax block in viewport. More info here - Issue 13.
zIndex	number	-100	z-index of parallax container.
disableParallax	RegExp / function	-	Disable parallax on specific user agents (using regular expression) or with function return value. The image will be set on the background.
disableVideo	RegExp / function	-	Disable video load on specific user agents (using regular expression) or with function return value. The image will be set on the background.
automaticResize	boolean	false	Experimental! Automatically recalculate parallax size and position when the size of parallax block changed (dynamic content inside). Uses ResizeObserver, which has a small browsers compatible. Recommended using with polyfill https://github.com/que-etc/resize-observer-polyfill.

Disable on mobile devices

You can disable parallax effect and/or video background on mobile devices using option disableParallax and/or disableVideo.

Example:

jarallax(document.querySelectorAll('.jarallax'), {
    disableParallax: /iPad|iPhone|iPod|Android/,
    disableVideo: /iPad|iPhone|iPod|Android/
});

Or using function. Example:

jarallax(document.querySelectorAll('.jarallax'), {
    disableParallax: function () {
        return /iPad|iPhone|iPod|Android/.test(navigator.userAgent);
    },
    disableVideo: function () {
        return /iPad|iPhone|iPod|Android/.test(navigator.userAgent);
    }
});

Options For Video (+ supported all default options)

Required jarallax/jarallax-video.js file.

Name	Type	Default	Description
videoSrc	string	null	You can use Youtube, Vimeo or local videos. Also you can use data attribute data-jarallax-video.
videoStartTime	float	0	Start time in seconds when video will be started (this value will be applied also after loop).
videoEndTime	float	0	End time in seconds when video will be ended.
videoVolume	float	0	Video volume from 0 to 100.
videoLoop	boolean	true	Loop video to play infinitely.
videoPlayOnlyVisible	boolean	true	Play video only when it is visible on the screen.

Options For Element Parallax

Required jarallax/jarallax-element.js file.

Name	Type	Default	Description
type	string	element	Will only work with element value.
speed	mixed	0 0	Parallax distance in pixels. Supported Y and X axis. Example: 100 200. Also you can use data attribute data-jarallax-element.
threshold	mixed	null null	Specify threshold for the parallax effect to kick in. For example, if you pass 0 0, the element will start to move only after it has been scrolled to the middle of the viewport.

Events

Events used the same way as Options.

Name	Description
onScroll	Called when parallax working. Use first argument with calculations. More info see below.
onInit	Called after init end.
onDestroy	Called after destroy.
onCoverImage	Called after cover image.

onScroll event

jarallax(document.querySelectorAll('.jarallax'), {
    onScroll: function(calculations) {
        console.log(calculations);
    }
});

Console Result:

{
    // parallax section client rect (top, left, width, height)
    rect            : object,
 
    // see image below for more info
    beforeTop       : float,
    beforeTopEnd    : float,
    afterTop        : float,
    beforeBottom    : float,
    beforeBottomEnd : float,
    afterBottom     : float,
 
    // percent of visible part of section (from 0 to 1)
    visiblePercent  : float,
 
    // percent of block position relative to center of viewport from -1 to 1
    fromViewportCenter: float
}

Calculations example:

Methods

Name	Result	Description
destroy	-	Destroy Jarallax and set block as it was before plugin init.
isVisible	boolean	Check if parallax block is in viewport.
onResize	-	Fit image and clip parallax container. Called on window resize and load.
onScroll	-	Calculate parallax image position. Called on window scroll.

Call methods example

A. JavaScript way

jarallax(document.querySelectorAll('.jarallax'), 'destroy');

B. jQuery way

$('.jarallax').jarallax('destroy');

No conflict

If you already have global jarallax variable or jQuery.fn.jarallax, you can rename plugin.

A. JavaScript way

var newJarallax = jarallax.noConflict();

B. jQuery way

jQuery.fn.newJarallax = jQuery.fn.jarallax.noConflict();

For Developers

Installation

• Run npm install in the command line. Or if you need to update some dependencies, run npm update

Building

• npm run dev to run build and start local server with files watcher
• npm run build to run build

Linting

• npm run js-lint to show eslint errors
• npm run js-lint-fix to automatically fix some of the eslint errors

Test

• npm run test to run unit tests

Real Usage Examples

• Khaki
• Godlike
• Youplay

Credits

Images https://unsplash.com/ Local Video https://videos.pexels.com/