Comment by j-pb | Hacker News Reader

Comment by j-pb | Hacker News Reader

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Almost no documents properly support ctrl-F. You'll get at best single word search, but you won't find coherent sentences. There are arbitrary line-breaks caused by various styling and layout packages (most columns are broken). There are even publishers that purposefully put garbage into the PDF's text layer as a braindead form of "piracy protection".

PDF and TeX are broken beyond repair in terms of accessibility. The former because it allows the text and image to be split, and very few people care about text as long as it looks alright. And the latter because it's entire document representation model is based around computation. Knuth purposefully made it Turing complete in a misguided attempt at timelessness (no need for a replacement if it's infinitely extensible right?), which means there is no proper way to view a TeX document as "just text data".

I've worked in a library digitising documents, and whenever we encountered PDFs we'd just OCR the damn thing.

We need to throw the thing out, swallow the bitter pill of sub optimal kerning, and replace it with HTML asap.

> PDF and TeX are broken beyond repair in terms of accessibility.

All that needs to be done is to have a accessible text section of the PDF--then Tex can just include the source of the document minus the Tex commands into the PDF, and PDF readers can have the screen reader work. The text could also just be stored per page, if the blind require to communicate where they found a particular item to a sighted person.

As I already wrote.

PDF already has exactly that. They separate they have a view layer and a text layer.

But it simply doesn't work, because people can't be bothered to get the text right, once the view layer is acceptable.

Also TeX minus the tags, is not the final text in any way, because it's not markup, it's code.

> But it simply doesn't work, because people can't be bothered to get the text right,

That's hardly "it's broken beyond compare." I think with accessibility formats which represent fully typeset written documents (as opposed to pre-typesetting, like Latex), it's always going to be an issue because they're mainly produced for people who are sighted initially.

We should simply start shaming programs which export to PDF wrongly, it's not really a difficult thing to get right.

"The way a tool is used is the way that is encouraged by the tool."

Knuth is one of the most perfectionist computer scientists out there, and he still got it wrong.

The market economics are simply not in the favour of people doing extra work, and no amount of shaming will get that to change.

The alternative needs to be designed with accessibility builtin, and with decidability/markup as a conscious design choice.

We have such a format, HTML. The chances to get academics to use HTML with the coming open access wave are much better than getting them to rewrite all of their TeX templates.

I disagree, I mean HTML would be even worse for text-flow if you rendered a PDF directly to HTML. The text-flow of HTML is not guaranteed, in the same way that the PDF text section is not guaranteed to be correct.

It's more about the social economics --but if you can find me a tool that supports the PDF export wrongly, I'll fix it myself.

> The market economics are simply not in the favour of people doing extra work,

Most of the tools are open-source. Does Word or any of the closed source tools do a bad job of this? That would be the main stopping point I guess.

It's still super trivial for them to implement, and shaming them will get their PR team evaluating the risk of not implementing such a feature. You just have to be successful at shaming them.

An HTML file also doesn't represent a document on paper, most people writing papers wouldn't switch to a electronic-only format at the moment--each page is carefully typeset and designed, HTML is not at this level even today.

Minus the tex commands doesnt work for maths and tables, they are almost all tex commands.

Let's take an example:

https://arxiv.org/pdf/1606.06389.pdf

A cursory inspection seems to indicate ctrl-F is fine here? Or am I missing something?

Single column layouts often work semi-acceptably for text only, when not purposefully tampered with.

However if you try to select the text on page 2, you'll see that the layout engine didn't actually place the formula into its own section. Not only is it broken, with the sum signs missing, it is also jumbled up with the text below it, resulting in weird - text broken formula - text - broken formula - mumbo jumbo.

This would make it extremely hard if not impossible to properly follow the paper with a screen reader.

The figures on page 6 also produce weird artefacts on the text layer. In HTML for example you'd simply present the alt-text to the person with the screen reader, but TeX doesn't have such a feature in most vector drawing libs afaik.

The table on page 8 is also not correct in terms of the text layer. If you select it you can see that you get the top half of the leftmost column followed by the rightmost column, followed by the rest in some order.

If I may also direct your attention to this gem on page 9: "Then at least half of allnodeshaveh ̄=lgn =lgn−1(seethepaperforthedefinitionofh ̄),and 2√ thus a potential of Ω( lg n). Therefore, the total heap potential would be lg n). Conjecture: the same construction works for the fancy potential √ √ function, which would give a bound of Θ(n · 4 lg lg n)."

Shall I go on ^^?

No need to go on, that's already more than I bargained for, thank you so much for taking the time to respond :)

I suspect we're using different PDF viewers; I'm using the one that comes with my browser.

The results are somewhat less disastrous than you describe, but still bad. (I'm seeing maybe half the problems you mentioned.) I'm a bit curious which viewer you're using.

I can describe what happens when I copy/paste the stuff you mentioned on pages 2/8/etc., and if you're interested I will, but if you're not interested let me ask a slightly different question:

Rather than try to get the screen reader to make sense of the final PDF, would it be easier to just download the original page source from arxiv and let the screen reader deal with that?

I was using the builtin viewer of chrome I think, could also have been safari.

Using the original TeX source for the screen reader is significantly hindered by the fact that TeX isn't a markup-, but a programming language.

TeX is turing-complete by design, making it infinitely extensible, in order to avoid knuth ever having to re-typeset his books. After all if it's a programming language and a new system, problem, style, e.t.c, comes along you can just write a program that deals with it.

But this has horrible effects on render-ability, in order to know what the final document should look like, you need to run it, no way around that, thanks to Rice's theorem.

LaTeX users also generate a lot of their figures with TeX itself, write their own styling or bibliography rules, and write their own custom graphics rendering libraries.

The easiest path is to just give up, render the entire PDF to a 300dpi lossless image, and throw it into an OCR engine. These things contain a buttload of heuristics to generate structure and meaningful text based on visuals, and since we know that humans explicitly (and often only) care about those in TeX documents...

It's pretty darn sad, because in many ways TeX is holding scientific advances back, by eating its own children. My guess is that if scientific papers had branched off of plaintext tools like troff, we'd probably publish papers as machine readable semantically annotated knowledge-graphs by now.

I just tried in Chrome; at least for page 2 it actually did a bit better than my browser: it actually managed to preserve the line breaks! (I don't have Safari installed.)

(Also, if you look closely, the summation signs are not gone, they are replaced by the letter P. Which is not helpful I admit.)

Do you think there's any place here for education/advocacy? For instance, everyone who makes web pages knows to provide alt text for images.

If there was a standard package that everyone knew they had to include or else it breaks everything from ctrl-F to copy/paste to screen readers, presumably people would use it, right?

I'm less interested in speculating what would have been if troff had "won", (though it is indeed fun to speculate), and more interested in how to fix the mess we're in now, so that 10 years in the future, blind people have better choices than OCR.

(Though OCR is still an improvement over the best option in the 1980s I bet. Though I wasn't around so just guessing.)

"Do you think there's any place here for education/advocacy? For instance, everyone who makes web pages knows to provide alt text for images."

That's not a culture thing, this is by the mechanism of <img alt. You won't get people who write TeX to change all of their workflows, and even if there was such a culture.

"If there was a standard package that everyone knew they had to include or else it breaks everything from ctrl-F to copy/paste to screen readers, presumably people would use it, right?"

Then it would still be nigh impossible because TeX commands, like all programming languages, compose rather poorly. It would be a herculean effort to produce a kinda but not really TeX that is both accessible with a focus on semantics, yet still compatible with the billions of lines of LaTeX/TeX out there.

"I'm less interested in speculating what would have been if troff had "won", (though it is indeed fun to speculate), and more interested in how to fix the mess we're in now, so that 10 years in the future, blind people have better choices than OCR."

Boycott LaTeX/TeX and PDF everywhere you can. Whenever you publish a paper, also publish it in markdown/html. Publish in OpenAccess Journals like [PeerJ](https://peerj.com/) which convert all of their papers to html in addition to pdf. Consider publishing papers in alternative forms like nextjournal.com .

We need to get our priorities straight in academia :/. This entire "but latex produces such beautiful documents", "I'm working towards getting into the most prestigious journal" culture of snobbery and vanity needs to stop. We need to go back to caring about the content, not the presentation, something TeX ironically was meant to do.

So basically, give up on LaTeX to PDF as the primary workflow. Either convert LaTeX to semantic HTML instead of to PDF (probably doable for simple cases... \emph to <em>, \section to <h2>, \begin{tabular) to <table>, and so on), or better yet just author HTML without going through LaTeX at all. If needed, convert the semantic HTML to PDF as well, for printing or whatever, and then the PDF might end up sane.

Fine, fair enough. If fixing TeX is hopeless, then so be it. I assumed it just needed a few small tweaks, maybe combined with slightly cleverer PDF viewers. Guess I was wrong.

But then what should people use for math? I suppose there's MathJax, which seems to have put some thought into accessibility.

There's still a problem though. I can't help but notice that the journal you linked to is a biology journal. In some math/CS circles which are TeX's "home turf", TeX is far more entrenched to the point where I'm not sure such things even exist. For instance, arxiv sort of supports HTML, but not really:

https://arxiv.org/help/submit_html

So there I guess step 1 is to make HTML a viable option.

PeerJ has actually quite a few publications, one of them is CS ;) https://peerj.com/computer-science/ the dropdown on the top left allows you to switch between them.

I think MathJax is certainly a step in the right direction, they even support rendering to MathML.

But I agree that there is a certain lack there in terms of full semantic representations. MathJax is more accessible than TeX but it's still describing visual layout, instead of semantic meaning.

Pushing HTML to arxiv is also a step into the right direction.

I think the most important thing we can do is not be complacent with the state of the art. We need to go back to an age of computing where we didn't think we had it all figured out. We need to experiment, and not be afraid to take a step back in some aspects, like layout and kerning, in exchange for other advances like semantic representations and knowledge representation.

I think bred victor has a great talk on this: https://www.youtube.com/watch?v=8pTEmbeENF4

I think we need to experiment with things like observablehq.com or nextjournal.com or the many other that are coming into existence.

re: PeerJ: I missed that, nice!

re: semantics vs visual layout of math... Wikipedia says OpenMath is a thing, but... that only solves half the problem. Once you have a format that encodes what you want, someone has to actually it.

Like, if some writes x^{-1} and f^{-1}, it's hard for a computer to figure out that the first one means "the number you get when you divide 1 by x", whereas the second one means "the function you get when you compute the inverse of f".

And if the author can't be bothered to slow down and say which is which, then the reader will have to guess.

re: HTML to arxiv: not ready for prime time, if you actually follow that link.

re: kerning: TeX's advantage here is not fundamental, I think. Just need a good font, as far as I know. (Actually that's not far; I know almost nothing here.)

re: layout: CSS is finally getting good at this from what I hear.

re: talk: looks familiar; maybe I should re-watch it.

Try copying across a line break. You'll notice that the spaces between the words are missing when you paste it.

Just tried copying across a line break on page 9, seems to work:

Here the potential function is, to say the least, not very simple.

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