What is the optimal distance between braille lines for the Swell Braille and Braille29 fonts in tactile graphics? In Inkscape, the setting is for the distance between baselines. Do you also know the setting for that in both fonts (with Swell Braille at 24 pt. and Braille29 at 29 pt.)?
When creating TGs for reproduction on a Tiger embosser you should use the Braille29 font with 100% line & paragraph spacing.
However, the Braille29 font should not be used when reproducing materials on microcapsule paper.
The Swell Braille font was originally developed for use with microcapsule paper and is 24pt in height. 24pt is smaller than the specifications established by the U.S. Library of Congress, but this is necessary so that when the microcapsule paper is run through a fuser, the braille can swell to approximately 29pt high.
However, the default line and paragraph spacing for a 24pt font will be too small to accommodate the swelled dots, and lines will be too close together. For this reason, when using the Swell Braille font for reproduction on microcapsule paper, you should set the line and paragraph spacing to 111%.
If Inkscape does not allow setting line spacing to 111%, set it so baseline-to-baseline distance is 5mm (0.19685 inches) when using the Swell Braille font.
In GSTG, Appendix D.2, you will find more information about setting up braille in TGs for microcapsule paper.
In that appendix, GSTG indicates that the Swell Braille font can be downloaded from the Duxbury website, but it is no longer available from there. However, TSBVI (Texas School for the Blind and Visually Impaired) maintains an excellent archive of materials useful to braillists and TG producers, and the Swell Braille font can be downloaded from that website <https://www.tsbvi.edu/download-braille-and-asl-specialty-fonts>.
Please let us know if this answers your questions!