[poppler] Why TrueType vertical glyphs for Adobe-CNS1, -GB1, -Korea1 use "kana" script tag?

[Koji Otani]

Because I had not enough knowledge about Chinese and Korean fonts, I
think.
I'll appreciate it if you would fix them.	
----------
Koji Otani

From: suzuki toshiya <mpsuzuki at hiroshima-u.ac.jp>
Subject: Why TrueType vertical glyphs for Adobe-CNS1, -GB1, -Korea1 use "kana" script tag?
Date: Mon, 26 Mar 2012 18:03:58 +0900
Message-ID: <4F7030FE.8040005 at hiroshima-u.ac.jp>

mpsuzuki> Dear Otani-san,
mpsuzuki> 
mpsuzuki> During the testing for GlobalParamsWin.cc improvement with MinGW,
mpsuzuki> I found that the vertical glyphs for Adobe-CNS1, -GB1, -Korea1
mpsuzuki> with external (non-embedded) TrueType fonts do not work well with
mpsuzuki> Chinese/Korean TrueType fonts bundled to Microsoft Windows; SimSun,
mpsuzuki> MingLiU and Batang.
mpsuzuki> 
mpsuzuki> The reason is very clear; FoFiTrueType::setupGSUB() prepares the
mpsuzuki> vert or vrt2 GSUB features for default language system and specified
mpsuzuki> script. In current poppler, "kana" script tag is used in all cases
mpsuzuki> of Adobe-CNS1, -GB1, -Korea1. But SimSun, MingLiU, and Batang fonts
mpsuzuki> have no layout features for "kana" script tag (furthermore, these
mpsuzuki> fonts do not know anything about "kana" script).
mpsuzuki> The reason why "kana" is used always is because of your patch applied
mpsuzuki> on 2007:
mpsuzuki> 
mpsuzuki> commit 14a8361039d708661b8699b2e7c4496135021a85
mpsuzuki> Author: Albert Astals Cid <aacid at kde.org>
mpsuzuki> Date:   Fri Jul 13 22:18:05 2007 +0000
mpsuzuki> 
mpsuzuki>             * fofi/FoFiTrueType.cc
mpsuzuki>             * fofi/FoFiTrueType.h
mpsuzuki>             * poppler/CairoFontEngine.cc
mpsuzuki>             * poppler/CharCodeToUnicode.cc
mpsuzuki>             * poppler/CharCodeToUnicode.h
mpsuzuki>             * poppler/GfxFont.cc
mpsuzuki>             * poppler/GfxFont.h
mpsuzuki>             * poppler/SplashOutputDev.cc: Patch by
mpsuzuki>             Koji Otani <sho at bbr.jp> to fix several problems with Japanese fonts.
mpsuzuki>             Fixes bug 11413
mpsuzuki> 
mpsuzuki> Could you explain the background why you used "kana" for all cases?
mpsuzuki> Or, you can list the fonts that you used for testing your patch in 2007.
mpsuzuki> 
mpsuzuki> I think using "hani" for Chinese, "hang" for Korean is safer, but
mpsuzuki> if there are many Chinese/Korean fonts using "kana" script tag (and
mpsuzuki> not using "hani" or "hang" tags for vertical shaping), more enhancement
mpsuzuki> for vertical glyphs is needed. I will work for it.
mpsuzuki> 
mpsuzuki> Regards,
mpsuzuki> mpsuzuki
mpsuzuki>