Comment by wolfi1

9 hours ago

Knuth touches the reason for writing TeX et al.- briefly in this paper. He wanted the second edition of his TAOCP to be printed with exactly the same typography as the first edition, but the publishers told him at first they wouldn't have the Linotype machines anymore, with which they printed the first edition. But Knuth wanted to preserve the typography for the other volumes and other editions, so he set aside the TAOCP and began researching typography and writing TeX et al. Took him a long time before he could return to TAOCP. Btw, the second edition got finally printed with Linotype as these machines still existed in Europe

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wolfi1

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svat  3 hours ago

Actually:

• He had already published the first editions of Volume 1, 2, 3, and the second edition of Volume 1, by 1973. It was in 1977 when the publishers sent him galley proofs for the second edition of Volume 2, having switched to phototypesetting (away from hot-metal typesetting a la Linotype, though IIRC it was actually Monotype) that he was disappointed with the results. And he had some back-and-forth with them and they did improve their fonts (> I asked if I could use Xerox's lab facilities to create my fonts. The answer was yes, but there was a catch: Xerox insisted on all rights to the use of any fonts that I developed with their equipment. Of course that was their privilege, but such a deal was unacceptable to me: A mathematical formula should never be "owned" by anybody! Mathematics belongs to God.

• So he went home and (after trying a bit with TV cameras) tried projecting photographs of the pages onto the wall and tracing the outlines, and it was while staring at these images that he realized that the shapes of letters were not arbitrary but there was some logic to them (e.g. in the font he was using, the spacing between the vertical strokes in 'm' was equal, and equal to that in 'n'), and he decided (as a computer programmer) to capture this design in code — something that had never before been done. The hardest letter to capture this way is S, hence the paper in the OP.

> Finally, a simple thought struck me. Those letters were designed by people. If I could understand what those people had in their minds when they were drawing the letters, then I could program a computer to carry out the same ideas. Instead of merely copying the form of the letters my new goal was therefore to copy the intelligence underlying that form. I decided to learn what type designers knew, and to teach that knowledge to a computer.

• This is also why METAFONT never really caught on among typographers: as Charles Bigelow (quoted by Richard Southall, https://luc.devroye.org/Southall-METAFONT1986.pdf) observed, “the designer thinks with images, not about images”. Knuth did not want crude “geometric” constructions of letters (as some prior 16th century typographers had attempted: https://www.ams.org/journals/bull/1979-01-02/S0273-0979-1979... and as some typographers only passingly familiar with METAFONT think!). He wanted actual real typographically beautiful shapes, but to be able to generate those shapes with code. This is obviously much harder than simply drawing the shapes using visual intuition, even if it enables variation. (See “The Concept of a Meta-Font”:

drfuchs  3 hours ago

Not so about the Linotype. Back in 1980, I personally ran the Alphatype CRS phototypesetter (bought by DEK for the purpose), in the basement of Margaret Jacks Hall, that produced the entire camera-ready copy of The Art Of Computer Programming, Volume II, Second Edition. The DVI files and Computer Modern fonts were created by the early, Sail-language, 36-bit versions of TeX and Metafont that were later redesigned and implemented to be more cross-platform. Knuth rewrote the firmware that resided on the Alphatype (in 8080 assembly language), and I wrote the code that translated from DVI and drove it from the DEC20 mainframe over a serial line (trickier than it sounds; see our joint paper "Optimal prepaging and font caching" ACM TOPLAS Vol 7 Issue 1).

goolz  5 hours ago

I just want to add that they are a gorgeous set of books and I am so happy he did this. While a good chunk of the content is above my pay grade it is still enjoyable to flip through them and read about things like MIX. Gorgeous typesetting. And his writing is so very engaging for such a dense topic.

  • WillAdams  4 hours ago

    All of his books have been great, and he is the next author whose oeuvre I am going to try to collect (and read) in its entirety --- will finish up Tolkien this year when the second Myths and Legends box set is released in the U.S. and I can replace my ratty photocopy of _The Book of Exodus_ which was sent to me the second time I requested it on Interlibrary Loan.

WillAdams  4 hours ago

Note that they weren't directly printed with a hot metal casting machine (I believe Monotype was used, since it output discrete letters which did not need to be sawn apart as the Line of Type the competitor used), but rather what could be composed on a hot metal casting machine was, then additional spacing material and special characters and extensions which weren't available from that keyboard were sourced and the whole put together as a composed galley, then a proof was pulled and once approved, printed, then photographed to make a negative which was then used to make an offset plate for actually printing the book.

golem14  8 hours ago

Suddenly, I don't feel so bad about my own procrastinitis.