Chapter 33 Conversion to Braille
There is a conversion to braille which works very well, while also needing further improvements. Conceptually, it is not very different than the EPUB conversion (Chapter 31), except for the additional necessity of the
liblouis library for the translation of literary text (see Appendix G). MathJax and Speech Rule Engine provide Nemeth Braille from your authored LaTeX mathematics. There is the option of embossable braille (designed for a physical paper page) or electronic braille meant for an electronic device like a one-line reader with mechanical raised pins. It is worth the effort to first make sure an EPUB conversion is successful, and then extend to the braille conversion.
Some extra care needs to go into the authoring of a PreTeXt project that creates the best possible output as braille. Some aspects are obvious, such as not being overly-reliant on video or interactive demonstrations. We can accomodate some constructions like a
<sidebyside> in a way that makes sense to the reader. An allied project hopes to make it easy for authors to create diagrams that work well for both sighted and blind readers (tactile graphics). But constructions like abusing an
<m> element to get a superscript “th” will just lead to confusion for a braille reader. With experience, we are collecting suggestions for authoring in Section 4.34.
Please be in-touch in the PreTeXt discussion groups if you have a PreTeXt project you would like to convert. Of course, we want to improve the process and the result, but we are especially interested in the experience of blind and low-vision readers who can point us to areas that need improvement.