I am opinionated about fonts. A large part of this stems from Sensory Processing Disorder making many typefaces appear to warp or even accordion-fold the surface they sit on.

The worst offenders are transitional and Didone serifs, such as Times Roman and its clones/derivatives. I would particularly like to see Times New Roman die in a dumpster fire and be replaced by Bitstream Charter or Charis SIL, which are the only transitional serifs that don't torture my brain.

Old-style serifs are also okay in print material. I've never seen a book in Charter/Charis, but the difference between TNR and Garamond is the difference between functional dyslexia and reading 3 times as fast as I can talk, with high retention.

The problem is that WAY too many pdfs are printed mostly in TNR, and while pdfs can technically be edited even if they're not designed for that, different fonts take different amounts of space.

How might I find a sans font (humanist or grotesque) that is metric-compatible with Times New Roman? Also, some pdf edit tool with a replace-by-font feature would be helpful, no matter what platform it's for. I can convert to odt or docx online, but that does bizarre things to layout.

Liberation Serif

Liberation Serif is not a solution to the problem as stated. It is a "Transitional Serif" and is thus not a "sans font".

In fact, Liberation Serif is almost as bad as Times New Roman. ANY font that has a high variation in stroke width and a "vertical stress" will be problematic for the same reasons.

Sans-serif fonts are safe because their stroke-width variation is usually zero or almost zero. Charter and Charis are safe because their stroke-width variation is small. Garamond and other "old-style serifs" are safe because their stress is diagonal.

To clarify: I'm not looking for a straightforward TNR replacement. I'm looking for a dramatically different font that uses the same or similar bounding box dimensions for characters and line height.

Aah.
You want a sans-serif font to perfectly replace a serif font.
I have no answer unfortunately.
Crawling into the metrics of fonts is painful, I tried it once and in the end went with font substitutions others came up with.
But obviously you won't find a readymade substitution of a sans-serif font for a serif font.

I don't see why it needs to be the exact same metrics.

Have you done some tests with various fontconfig configurations?
Look in ~/.config/fontconfig/fonts.conf, /etc/fonts/conf.avail.
Also see here.

More here:
https://wiki.archlinux.org/index.php...mpatible_fonts

Liberation was specially constructed to solve the problem for MS Times and Arial, but I doubt that anyone will bother to solve your problem — if they have a document in a serifed font, most people will want to keep it that way if they change operating systems. Even using Liberation, the problem is only solved for horizontal layout. For some strange reason, most word-processors do not respect the embedded specification for vertical spacing, so a page may hold a different number of lines in different word-processors — or even in different versions of the same program.

I note that the Arch manual mentions the URW and Nimbus fonts. Unless someone has converted them, they are Adobe (Type 1) fonts, which are no longer supported by LibreOffice.

I do sympathise, since I too am opinionated about fonts. Some people have very strange ideas: I actually own a printed book set in Comic Sans! I use Linux Libertine (I suspect the German designer confused a libertine and a liberator) and Fontin in documents.

I wouldn't care about metric-compatibility at all if it weren't for pdf.

I have to screen college courses before signing up just to make sure I can read the textbooks. PDF versions of textbooks are often available, but the layout of modern textbooks involves so many aside boxes and nonlinearities that using a screen reader is almost impossible.

Replacing fonts without metric-compatibility damages such complex layouts to the point that text often overflows from its containers and overlaps other text. I could theoretically shrink text, but I know no way to proportionally shrink all text in a given typeface regardless of its original size. Manually selecting text is not an option, as I'm talking about doing this to book-length pdf files on a regular basis.

Regardless of whether fontconfig would work, I would prefer a platform-independent solution to modify files if possible. I'm currently on MacOS for Logic Pro and Retina Display, and Virtualbox gets more irritating every time I use it. At some point, I will probably build a native Linux system, but as of now I don't have the hardware.

I suspected from the beginning that this would be near impossible. I thought it was worth asking, though, as it's a distinct accessibility issue for me.
Preserving layout is usually only a problem in pdf. Specifically textbooks; all the frames, boxes, and nonlinear asides mean that layout needs to be fairly fixed. Editing them at all is a challenge, but I guess I'd like to know whether figuring out how to edit a pdf would actually fix anything before I jump through those hoops, so the line-spacing thing might be valuable information.

TNR is bad enough that it improves readability if I deliberately water-damage the paper. Do you think there's some way to do the same to a pdf? Like deliberately introduce compression artifacts with preference for dark pixels over light to simulate ink bleed?

As long as we're talking about fonts we actually like, I tend to go somewhere between grotesque and humanist. Roboto for UI (when it's not hardcoded), Oxygen for paragraph, Cantarell for 10px or smaller, Roboto Mono for code.

Turns out that happens to be almost exactly what I am working on for my packages of fonts ...

I do have a coordinated set of 8 metric compatible (MC) fonts in my "font folio" ... a folio that has yet to be released. I do have tools to aid in the development of MC fonts, so it might be not all that much work to build a "Times New Sans" type of font. Caveats would be numerous:

• Alternate glyphs that are used as character substitutions (e.g. “1/2” to “½”) in some fonts do not have the proper character width for the target glyph.

• Kerning information would not be compatible.

• The side bearings of each glyph would be set so that the advance width of each glyph aligns with TNRoman font. However, no changes in the contours of these characters have been made. Letter spacing would be off - can't yet say how bad.

If you would be open to testing a version of such a font, I might be able to do one fairly quickly ...

A web search for "accessibility fonts linux" turns up a number of articles that may help (note: the search returned more helpful results in Startpage than in Duck-Duck-Go).

Wow. I hoped a solution might exist, but I didn't suspect someone would consider going to *that* kind of trouble. I'm honestly not sure how I feel about asking that from someone. I'd definitely be open to testing, but only if there's some way I can reciprocate.

Several questions:
What characteristics would the sans-serif base for such a project need to have?
How much would the choice of a base affect the severity of spacing issues?
When you say "kerning information would not be compatible", is that the kerning of vanilla TNR, or kerning modifications specific to a given PDF?

I have several choices of open-source "base" font for this, and with the tools I have, this would be a minor (micro) extension to my pipeline. I'm doing all this programmatically, so there's not a lot of work involved ... however ...

I just realized that you need to replace a font *in* a PDF. I don't know how to do that. My fonts are intended to be used in straightforward authoring situations - Microsoft Word and Save As PDF, for example. I have no experience with swapping fonts in PDF ... Is that straightforward? Possible?

There is software that can edit PDF files in depth. However, I don't know if any of those tools can select by formatting. This means that I might have to go through entire books changing one textbox at a time. At that point, it's not really any easier than recreating the entire book in ODT form.

A screen reader *could* be just as good, if it has redundant text output or can speak intelligibly at 3x speed. So could any method to darken and soften the document to simulate water damage or a leaky printer. Anything to bypass the stroke-width variation of a Transitional serif typeface.

I'm probably going to have to turn down the offer of a Times New Sans for the time being –*the more I think about the issue, the more I realize the entire premise of this thread is flawed. It's not just Times Roman and Times New Roman I need to escape, it's the entire group of Transitional Serifs, save Charter and Charis. It's not like replacements are going to exist for more than one or two (if that), so my time might be better spent on finding a blanket solution rather than relying on metric-compatibility.

What I really need is to figure out how to English the question I should have asked in the beginning.

OK for now. But, since TNRoman is *so* prevalent, I might add a "Times New Sans" to my font set, and see if the availability finds a use ...