Conversely, English has a joined form(cursive) that is nearly dead because mechanical text assistance devices (first typewriters, now computers) work much better with the block form. While sad in a cultural loss sort of way the joined form only really makes sense when the text is hand written.

I am not familiar with the history of Arabic typography, but I sort of assume there was an archaic block form and their current joined form is the result of many centuries of encoding hand writing practice. advanced enough that falling back to a block form is impossible with the side effect of making simple mechanical text formatting also impossible.

As for Chinese derived characters. we currently are able to jam them awkwardly into our alphabet optimized structures(one code per character) but I wonder if a Chinese native encoding would look different. Would it make sense to try and represent the sub-characters present in each Chinese character in the encoding? I suspect not, Chinese works, but it also does not appear amiable to simple mechanical assistance.

Both Latin and Chinese have been modified by the technology used to write them.

When carved in stone the lines are much straighter. When written with brush or pen they became semi-cursive. When printing was introduced, they became grid-like and regular.

What westerners who are passingly familiar would think of as the standard Chinese typeface - the strict square grid with straight-line characters - arises in part from printing technology. Easy to carve that into wood blocks, and easy to line up the slots into a grid.

Latin was similarly morphed to fit into the realities of printing in the 1500s. And is still being morphed. Notice how numbers 123... are in-line and at the same height as the letters. That's a very modern convention, typewriter and computer influence on our orthography. Traditionally digits were more likely to appear as subscript, off-centre.

awesome article! i appreciated the alternatives and misc. workarounds to OT/unicode typesetting toward the end, very helpful :D (go blue!)

I think he's talking about the rendering algorithm with regards to the stream of text. essentially saying rendering direction should follow reading convention.

on the other hand, in formal arabic, it's not unusual that numers are read in clusters from least significant to most significant (right to left). 1984 would be read : eighty four and nine hundred and a thousand. not sure if the author is aware of this

But a message about your Door dasher also likely wouldn't be justified.

That might be because of translations from Arabic. The article was also posted on a different website where the author responded

> the Kashida section was contributed to this post from a talk in Arabic of Nawal Hadeed, which she translated and added to the post herself. Although I'm unsure of LLM usage in the translation process, looking at the original Arabic I felt some change in tone while editing the post. I could have either declined the translation and never have this documented, procrastinate in translating it myself (which has been ongoing for a while), or publish as it is. I found the last least damaging.

Same, and it is a shame. Reading it is wearisome.

It does seem like a KP-like algorithm ought to be able to optimize the break positions without extreme algorithmic difficulty aside from the inputs being considerably more complex than for Latin block print: the cost function for a proposed line is a straightforward [0] calculable function of the contents of the line, and I think one could make a dynamic programming algorithm that tracks, for each input position, the cost of the optimal layout of all text up to that position with a break at that position. This gives an algorithm that takes cubic time. (For input length n, you need to fill in n values in the table. Each value scans the entire table before that position and does a calculation with complexity linear in the proposed line length.)

As a practical matter, there’s an input length n and there is some upper bound B on a credible line length as measured in code points, so there are only at most n*B credible proposed lines to evaluate, which also limits the useful look back on the table to B positions, so I think the time complexity could be reduced to O(n*B^2) without making the results worse on reasonable inputs, and this is probably quite tolerable.

[0] Straightforward once you’ve implemented the whole Arabic rendering stack, anyway. I am certainly not qualified to calculate this function :)

> but when rendering you could stretch individual glyphs to the desired width

“Individual glyphs” :)

It’s Arabic, so you wouldn’t stretch a single glyph, id would have to e done after shaping so you can work out the next run (either a single Aleph or the joined characters) in order to know what is stretchable (then throw it to your layout step)