sirithink / scrollreveal.js

Declarative on-scroll reveal animations.

#scrollReveal.js ####Declarative on-scroll reveal animations. A simple way to create and maintain how elements fade in, triggered when they enter the viewport. An open-source experiment by @JulianLloyd

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##See Demo

Disclaimer: Please bear in mind that this plug-in is an experimental stage, and that breaking changes are virtually guaranteed in future updates.

##1. Installation Clone or download scrollReveal.js into your JavaScript folder, and reference it just before the closing </body> tag. It will automatically instantiate ready-to-go when the DOMContentReady event fires.

    // Everything else
    // ...

    <script src="js/scrollReveal.js"></script>
</body>

NOTE: scrollReveal.js does not require jQuery, but does rely upon CSS3 transitions; it has been developed exclusively for modern browser use only.

##2. Usage By adding a data-scrollreveal attribute to an element, it will automatically be revealed (using default values) as soon as the element is within the viewport.

Fig 1:

<h1 data-scrollreveal> Hello world! </h1>

However, scrollReveal.js allows you to define custom reveal behavior, using descriptive language.

Fig 2:

<h1 data-scrollreveal="enter from the top and move 50px over 1.33s"> Foo </h1>

<p data-scrollreveal="move 66px and enter from the bottom after 1s"> Bar </p>

<button data-scrollreveal="enter from the bottom over 1.1s but wait 2.5s"> Baz </button>

###2.1 Keywords, Values and Fillers Whatever string is passed to the data-scrollreveal attribute is parsed for specific words: keywords that expect to be followed by a value, and semantic fillers that facilitate more natural language.

####2.1.1 Keywords and Values These words describe the reveal behavior, using keyword / value pairs.

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• Enter — Controls the direction of your element transition. Whatever value is passed is considered the vector origin. For example, specifying top will reveal your element with a downward motion.
  • Accepted value: top, right, bottom or left → (eg. enter top)

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• Move — The distance your element will travel during transition.

• Accepted value: [ integer ] px → (eg. move 33px)

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• Over — The duration of your element’s transition.

• Accepted value: [ decimal ] s → (eg. over 1.66s)

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• After/Wait — The delay before your element beings its transition.

• Accepted value: [ decimal ] s → (eg. after 0.33s or wait 0.33s)

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2.1.2 Fillers

While keywords must be followed by an appropriate accepted value, the use of conjoining fillers are permitted for more readable language. These are shown below:

• from
• the
• and
• then
• but

Fig 3:

<!-- Eg. 3.1 — These 2 lines are equivalent -->
<div data-scrollreveal="enter top move 25px"> Example 1 </div>
<div data-scrollreveal="enter from the top and then move 25px"> Example 1 </div>

<!-- Eg. 3.2 — These 3 lines are equivalent -->
<div data-scrollreveal="enter left move 80px over 0.66s but then wait 3s"> Example 2 </div>
<div data-scrollreveal="over 0.66s move 80px but wait 3s and enter from the left"> Example 2 </div>
<div data-scrollreveal="after 3s, enter left and move 80px over 0.66s"> Example 2 </div>

3. Contributions / Thanks!

I noticed a growing number of clients were requesting on-scroll CSS3 transitions for various site elements, and so scrollReveal.js was made to help with development. If you’d like to contribute—please do!

Many thanks to @Codrops, @Mary Lou and the cbpScroller.js, © 2014, Codrops.

4. License

Licensed under the MIT License

Copyright © 2014 @JulianLloyd

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.