Typography in Application Design
Great application design relies on very limited use of graphical elements, the designer relies primarily on type to display data and establish the information hierarchy. PatternFly was designed to present clear, unobstructed content is critical to enable users to complete their tasks. Choosing the correct typeface and defining the right styles is not only important for users doing their job but it also is the primary element for setting the tone of the application.
Switching to Overpass
The current PatternFly typographical system is set on Open Sans, which was in the PatternFly beginnings an open project well maintained by Google. Google has since moved on and so have we. We chose to switch to Overpass because is important that we utilize the resources which have developed through open source methodologies. Red Hat has developed ‘Overpass’ as the corporate web typeface based on ‘Interstate’ which has set the tone as the brand standard. Overpass has been tested throughout Red Hat web properties and has been proven as a great alternative. It is time to make the switch.
There are many considerations when choosing the correct font specifically for application design such as: language coverage, weight variety, character shape, hinting, etc. Overpass has recently been extended to include two new weights and hinted to work great on low resolution screens. This will make the application content more accessible and allow the designers to continue relying on type as the primary way to establish the information hierarchy in our applications.
Moving to Overpass does have its challenges. The primary challenge is that it does not offer as much character coverage as Open Sans. To combat this we are mirroring the Red Hat web properties strategy of relying on a well tuned system font stack to display the correct characters for any language.
Making the transition
PatterFly is going through a period evolution. There is no better time to make this change then now. We are taking this opportunity to make changes to our designs which includes changing to Overpass as well as increasing the base sizing and spacing. This change is a substantial effort which we plan to roll out in the next major PatternFly release.