Some of the discussion on this thread has been about drawing
programs.

For raw PostScript, I recommend the book, ``Mathematical Illustrations'':

    https://www.math.utah.edu/pub/tex/bib/master.html#Casselman:2005:MIM

Few people, however, are willing to write in a reverse Polish notation
language, like BibTeX style files, Forth, Postscript, and (text-form
of) PDF.

For drawings with connected labeled boxes, ellipses, circles,
diamonds, ... etc, consider Brian Kernighan's original pic

    https://www.math.utah.edu/pub/tex/bib/unix.html#Kernighan:1981:PCG

or its GNU successor, gpic. The latter is in all major Unix-family
distributions, and can easily be built from source code when it is
not; it is embedded in the groff package:

    ftp://ftp.gnu.org/gnu/groff/

For more complicated drawings, Asymptote produces impressive 2D and 3D
drawings:

    https://asymptote.sourceforge.io/gallery/

In the TeX typesetting community, TikZ has a supportive community:

    https://tikz.net/

Asymptote is packaged separately in many O/S distributions, and is
also part of the annual TeX Live releases:

    https://tug.org/texlive/

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