Is there a way to support CJK languages in one document without applying commands

Question

I cant seem to find a way to support all the CJK (Chinese, Japanese and Korean) lanaguages in one document.

Yes you can apply something like \ch{...} to render Chinese for example, however, is there a way to have it render the content without applying commands to the content. For example, how can I get the below to work without either some of the characters missing or square white boxes appearing on some characters

\documentclass{article}
\usepackage{xeCJK}
\begin{document}
Japanese: フォントはまた、数学的な形態および他の環境で使用することができるフォントはまた、数学的な形態および他の環境で使用することができる
Chinese: 关于数学部分 
Korean: 전체 문서에 대한 기본 정보를 소개 단락.
\end{document}

I would like to add one or more CJK content without having to apply commands for each of the languages.

I am happy to use XeLaTeX, LuaLaTeX etc... I have been playing with XeLaTeX as this supports characters better than others but I can't seem to get it to work.

I have spent a lot of time on this going around in circles and not be able to find a good solution without characters missing or white boxes appearing.

Help would very much be appreciated.

Answer 1

Only a partial answer since I don't know enough about these languages to help with proper language support like e.g. linebreaking. (You might want to look at babel and/or luatexja for that)

If you only need the font support to avoid missing characters you can use the multiscript font feature in LuaLaTeX: (This example requires Noto Serif CJK to be installed, but you can add four others fonts instead.)

\documentclass{article}
% You probably need luatexja and/or babel for linebreaking
% But here we will cheat for now and just use larger paper:
\usepackage[margin=1cm,a3paper]{geometry}
\directlua{
  \directlua {
  luaotfload.add_multiscript("cjk",
      {
        Hang = "Noto Serif CJK KR:mode=node;script=hang;",
        Hani = "Noto Serif CJK TC:mode=node;script=hani;",
        Kana = "Noto Serif CJK JP:mode=node;script=kana;",
        Hira = "Noto Serif CJK JP:mode=node;script=hira;",
      }
    )
  }
}
\usepackage{fontspec}
\setmainfont[RawFeature={multiscript=cjk}]{Noto Serif}
\begin{document}
Japanese: フォントはまた、数学的な形態および他の環境で使用することができるフォントはまた、数学的な形態および他の環境で使用することができる
Chinese: 关于数学部分
Korean: 전체 문서에 대한 기본 정보를 소개 단락.
\end{document}