A flexible code implementation of the GEL Typography.
Forms part of the GEL Foundations

v6.0.0 of GEL Typography implements the @use and @forward approach and removes @import.

This has a number of consequences; how modules are loaded, and how to access variables. Namespaces now come into play, so please read the sass documentation links above to learn more.

Previously, the properties output from this module could be controlled via three variables: $core, $enhanced and $fixed. These three variables allowed for control of the output, where core functionality could be separated out from enhanced functionality (for more advanced browsers) and for Internet Explorer (fixed).

As browsers have moved on significantly since this approach was adopted it is considered a good time to remove this functionality.

For usage of GEL Typography prior to v6.0.0 please reference the v5.2.0 readme.

An implementation of the GEL Typography Guidelines. Providing typefaces, type sizes, weights, line-heights and tracking. The GEL Typography scale has been established to work on all devices and is independent of device size and resolution.

The typographic scale has been optimised based on the size of the viewport and the input method being used. We take a 'touch first' approach to typography, adjustments are then made if a primary input other than touch has been detected.

It can used in two forms, using a Sass mixin:

@use 'gel-typography/typography' as type;

.my-component {
    @include type.gel-typography('canon-bold');
}

Or by simply adding the relevant classes to your markup:

<h1 class="gel-canon-bold">Global Experience Language</h1>

The easiest way to get started with the GEL Typography component is to use the combined version of the typography included within this repository.

If you're a more advanced user and want to integrate the GEL Typography component within your codebase, use one of the following options:

$ npm install --save gel-typography

// your-app/main.scss
@use 'gel-typography/typography';

You can install this component manually by downloading the content of this Git repo into your project and use a Sass @use to include it in your project.

Note: you will manually need to manage the dependencies below, without these this component will fail to compile.

Because this module depends on other modules, GEL Sass Tools and Sass MQ, when compiling your Sass it needs to know where find the referenced modules. It does this via a loadPath.

If compiling from the command line you can specify:

sass --load-path=node_modules/ <options>

With nodejs you can call compile or compileAsync:

await sass.compileAsync(file, { loadPaths: ['./node_modules'] })

This ensures the dependencies can be loaded correctly.

By default the GEL Typography component does not output any markup but exposes a Sass Mixin which can be called within your Sass.

Example

@use 'gel-typography/typography' as type;

.my-component {
    @include type.gel-typography('pica');
}

.my-component__title {
    @include type.gel-typography('canon');
}

A collection of typography classes can be output by defining $gel-type-enable--markup-output: true; as you @use the typography partial.

Example:

@use "gel-typography/typography" as type with ($gel-type-enable--markup-output: true);

The following configurable options are available:

• $gel-type-namespace: 'gel-'; - the default namespace applied to all typography classes
• $gel-type-touch-class: 'no-touch'; - the class exposed used by your touch detection script applied when a non-touch interface is detected

• $gel-type-enable--markup-output: false; - output a collection of classes for each type group
• $gel-type-enable--font-family: false; - output the correct font-family required by GEL Typography, required if the BBC's global header and footer, Barlesque, is not available.
• $gel-type-enable--base-elements: false; - map the GEL Typography classes to the relevant HTML elements

If you're using another font-face other than Arial and need to make adjustments to any of the type settings you can do this by defining in a custom $gel-type-settings map.

For example: BBC News support many languages, some of which do not use latin based character sets which require custom font scripts. It is often the case that these custom fonts will require bespoke font-sizes or line-heights.

For example, the configuration for Burmese may look like:

$gel-type-settings: (
    'trafalgar': (
        'group-a': (
          'font-size': 22px,
          'line-height': 30px,
        ),
        'group-b': (
          'font-size': 26px,
          'line-height': 36px
        ),
        'group-c': (
          'font-size': 38px,
          'line-height': 50px
        ),
        'group-d': (
          'font-size': 32px,
          'line-height': 32px
        )
    ),
    'trafalgar-bold': (
       ...
    )
);

We operate a touch-first approach to our Typography. Group C (touch) sizes are used from 600px by default and then detection should be used to get the Group D (non-touch) sizes.

We also understand that touch detection is not an absolute measure and does not guarantee a 'true or false' outcome - this is okay.

Products such as News & Sport require more densely packed, legacy-like font sizes for their 'desktop' experience. Eventually we aim to remove this group altogether.

There are a number of ways you can apply the touch detection. Modernizr, the common feature detection library offers some basic touch events detection. Alternatively, you could use your own bespoke detection script like this one used by BBC Sport.

The following teams are currently using this component: GEL, News, Sport, Live, Homepage, Search, BBC Food, CBBC, CBeebies, BBC Three, MyBBC, K&L, Taster, Academy, Travel & Weather, BBC Music, BBC Subtitle Guidelines

If your team is using this component, let us know and we'll add you to the list.

• Shaun Bent
• Al Jones
• Nikos Tsouknidas

• Sean Carroll

The MIT License (MIT)

Copyright 2016 British Broadcasting Corporation

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.