Re: org mode table alignment issue with CJK characters

[Zelphir Kaltstahl <zelphirkaltstahl@posteo.de>]

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On 3/23/23 15:44, Zelphir Kaltstahl wrote:
>
> Hello org mode users!
>
> I recently looked into getting org mode tables to properly align cell borders 
> and table border, when using Chinese characters in them.
>
> I found out, that there is valign mode [1] and was happy with it for a few 
> days. But then I opened a document with lots of tables and some of those 
> tables bigger than what I had before in other documents. Scrolling inside that 
> document became quite laggy. So teeth-gnashingly I deactivated valign mode, 
> already suspecting it to be the culprit. And I was right. After deactivating 
> it, I could scroll perfectly fine again.
>
> So I returned to the second alternative I had found out about, when searching 
> for a solution: Finding a font, which renders Chinese characters at exactly 
> double the width of latin/ASCII characters. I found a font named "Sarasa" [2] 
> and experimented a bit with setting the font globally, then setting it only 
> when opening an org mode buffer. Now it looks like that font does character 
> widths almost correctly (see attached screenshot, see slightly wider 4 ASCII 
> characters than 2 Chinese characters).
>
> My settings for org mode regarding fonts/faces are:
>
> ~~~~
> (add-hook 'org-mode-hook
>            (function
>             (lambda ()
>               ;; Only do the following in graphical mode, as it will
>               ;; break when using emacs in terminal mode.
>               (when (display-graphic-p)
>                 ;; Sarasa font is fromhttps://github.com/be5invis/Sarasa-Gothic.
>                 (setq buffer-face-mode-face
>                       '(:family "Sarasa Mono CL"
>                         :weight normal
>                         :height 110))
>                 (buffer-face-mode)))))
> ~~~~
>
> However, it seems, that now org mode does not align tables correctly, even 
> though an ASCII character is half the width of a Chinese character in the 
> tables. Org mode seems to add too few or too many spaces, which are displayed 
> as spaces of various width.—Is that because of the 1 pixel width difference?
>
> Do I need to look for another font, which does things truly exactly, no 1 
> pixel too wide funny business? Maybe someone knows a more exact font?
>
> Ultimately: How can I make tables align correctly?
>
> My Emacs version is: GNU Emacs 28.2
>
> My org mode version is: 9.6.1
>
> [1]: https://github.com/casouri/valign
>
> [2]: https://github.com/be5invis/Sarasa-Gothic
>
I have tried something else today:

I looked at how the font is rendered in Libre Office. There it seems, that the 
characters align perfectly (see attached screenshot). So maybe this is an Emacs 
in general issue of font rendering, which adds a pixel to ASCII characters or 
takes one away from CJK characters?

-- 
repositories:https://notabug.org/ZelphirKaltstahl

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