# PreFigure

### An authoring system for accessible mathematical diagrams

PreFigure is a system for creating mathematical diagrams to include in scholarly documents, such as research articles, textbooks, and other instructional materials. PreFigure is to figures what PreTeXt is to text.

Among its features, PreFigure:

- provides an intuitive language for describing diagrams so that authors focus on the meaning of their diagrams rather than the details of their construction and visual appearance,
- encourages the use of established design principles for effective communication,
- facilitates the creation of accessible diagrams that may be easily navigated with a screen reader or rendered in a tactile format, and
- will always be free to use and open-source.

To illustrate, here is the type of diagram that could appear in a calculus textbook. On the left is a typical image for including either on a web page or in print. Annotations can easily be added to enable a screen reader to navigate through the diagram. On the right is a tactile version of the diagram that could be embossed and included in a braille edition of the same document.

Both images are created from the same PreFigure source. Notice how this source reflects the mathematial structure of the diagram rather than the visual appearance.

<diagram dimensions="(300,300)" margins="5"> <definition> f(x) = exp(x/3)*cos(x) </definition> <definition> a = 1 </definition> <coordinates bbox="(-4,-4,4,4)"> <grid-axes xlabel="x" ylabel="y"/> <graph function="f"/> <tangent-line function="f" point="a"/> <point p="(a,f(a))"> <m>(a,f(a))</m> </point> </coordinates> </diagram>

## Additional resources

- Authoring Web-accessible Mathematical Diagrams, with Volker Sorge.
- Raised mathematics, Research and dissemination for accessible STEM materials

## Contact

David Austin, austind at gvsu dot edu