Calibre viewer playing poorly with Japanese (vertical) text

[Aster Selene]

Hello! This is my first time here and I'm not sure if variants of this question have been asked before or what, but I thought I might give it a shot.

So I happen to have a few Japanese books in my library, and one quirk about them is that they read right-to-left (both in terms of turning pages and in terms of actual reading lines), and everything is written vertically. Like so:



You start reading from the right line, read top-down, and move onto the next lines on the left.

Unfortunately, the fact they're this way tends to make eBook readers play very badly with them, as I presume they're accustomed to expecting lines to be horizontally read and vertically stacked as usual. Oftentimes they'll do things like have layouting problems, or parse the text incorrectly.

In the case of calibre, the layouting is preserved and even the furigana is kept, which is awesome. But...



The problem is that this is not the full chapter, but if you were to "flip a page", it would skip to chapter 2, without displaying the text that makes up the rest of chapter 1 (which is, as you can probably imagine, quite a lot of text). What it seems to be doing is displaying as much text as the current window or screen can possibly show, but since it doesn't register data that extends horizontally instead of vertically as being something that should be read through page flips, it registers a page turn as something that should skip all the way down to whatever's delineated as the next section, while whatever text was going off horizontally to the side is left unreadable due to the lack of a wide enough monitor/window.

I'm curious if anything can be done about this, whether through calibre itself, or through a plugin or whatnot (or if it's even been addressed already and I just haven't seen anything about it in the existing materials, or, heck, if maybe calibre already supports this and I'm missing something). I would appreciate it -- it's a bit difficult to deal with missing more than half of the text of the actual book! Right now the only real workaround is this plugin, which lets you actually go into the editor and convert the direction to horizontal, but as it can cause layouting issues (especially if the book in question has pictures), it would be helpful if support for reading in this direction could be possible natively.

[jhowell]

Are you using the latest version of calibre? This was supposedly fixed in calibre 5.

See the thread New programmer seeking to work on the lack of vertical/Japanese ebook formatting.