How does PTXprint implement grid typsetting?

Question

Grid typsetting (so that all lines match up on every page) seems to be implemented very well in PTXprint. LaTeX is in general not really good at handling this, there are only a few packages that have been developed returntogrid, grid), with limited functionality. Is PTXprint using one of these packages, or did you develop your own code to ensure text is aligned on the grid? I would be curious if I could use your grid functionality outside of PTXprint.

Answer 1

PTXprint uses about 30,000 lines of TeX macros on top of plainXeTeX. Extracting that into a general typesetting engine would be possible, but would take some work to get into a form that people could use. If you want to attempt this, we would be supportive. But notice that it also takes 30,000 lines of python to make the macros easy to use ;)