[PARKED] waiting on ReadiumCSS ... Japanese settings in src/utils/fontList.ts

[peaceroad]

In past versions, when the language setting was set to Japanese, settings for horizontal/vertical Japanese fonts were added in FontList.ts in the font selection.

I think I currently have the following problem:

• The displayed label names are difficult for Japanese speakers to understand.
• The same font is specified in both English and Japanese, but currently there should be no problem with the English font name.
• I don't think the font specification is modern. (Unless there's a reason.)
  • I am using MS Gothic, MS Mincho, etc. and it is difficult to view on Windows.
  • At Hiragino in macOS, I want to specify ProN, which specifies kanji with new glyph shapes.
  • Hiragino Sans GB specifies simplified Chinese characters.

In this pull request, I hope to have solved the above problem to some extent.

• The BIZ UD font may not be the best on Windows, but I think it's better, so I added it.
  (With Yu-Font's default settings, it appears a little thin and difficult to read.)

p.s.
Regarding specifying the font, I think it is difficult to solve the problem by simply specifying the font-family. For example, when Japanese is written vertically, ASCII characters may display rotating 90 degrees. In that case, you may also need to make adjustments using font-feature-settings.
If I have time...I would like to write about this in a separate issue at a later date.

[danielweck]

Great expert feedback, thank you very much :)
@JayPanoz I borrowed the original font face recommendations from ReadiumCSS, let's see how to backport the proposal here into RCSS

[danielweck]

https://github.com/readium/readium-css/blob/master/css/dist/ReadiumCSS-ebpaj_fonts_patch.css

[peaceroad]

Indeed, even with the settings in this pull request and running Thorium in the development environment, the font did not actually change.
Looks like I had to modify the r2-navigator-js package.
So I submitted a pull request.
readium/r2-navigator-js#79
I think now (probably) it will be displayed in BIZ UD fonts on Windows.

However, since I have not checked in detail, it is possible that this is a redundant specification or a strange setting.
I did a quick check. (The attached image shows this branch with r2-navigator-js modified.)

Another thing is that even before changing this font family, I have noticed that in vertical writing, there are cases where the leftmost sentence column is cut off. I haven't checked if it's already registered as an issue, but if not, I'd like to submit it as an issue later. (I don't know if this is a problem that can be fixed right away.)

[danielweck]

Thank you once again for looking into this. The navigator changes are actually directly related to the upstream ReadiumCSS project.

@JayPanoz could you please take a look? Adding the recommended font faces to the local stack seems like a safe and sensible action.

[danielweck]

Related: readium/r2-navigator-js#79

[peaceroad]

After that, I changed my mind and decided to use "Yu Gothic Medium" for sans-serif, which is pre-installed in the Windows Japanese environment. For now, it seems to be the most effective fallback for readability.

• This font has a weight of 500, which eliminates the difficulty of reading due to the thinness of the normal Yu Gothic

• Half-width ASCII characters in vertical display are not good with the BIZ UD font, so using the Yu font will solve this

I will commit after this.
I commented on this and committed to Readium-CSS earlier.
readium/readium-css#146 (comment)

Note that the Yu font (Yu Mincho Medium) with a weight of 500 for serif is not pre-installed in the Windows Japanese environment. Therefore, I left the BIZ UD font as the preferred font for serif.

[danielweck]

Resolution: readium/readium-css#146

[danielweck]

ReadiumCSS backport into navigator: readium/r2-navigator-js@17b86f2

[danielweck]

Fixed via 3a79251

Thank you @peaceroad