Do I need to use \usepackage[T1]{fontenc} if I use lualatex?

Question

When producing documents with pdflatex that may contain special utf-8 characters, it is recommended to add the following to the preamble

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}

I know that with lualatex the inputenc line is not necessary, since everything is set up to use utf-8 encoding by default. But I don't know what to do about that fontenc line. Do I need to include it or not if I am using lualatex?

Answer 1

If you want to use pdflatex, you should use in your preamble:

\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}

If you want to use lualatex or xelatex, you should use in your preamble:

\usepackage{fontspec}
\setsansfont{CMU Sans Serif}%{Arial}
\setmainfont{CMU Serif}%{Times New Roman}
\setmonofont{CMU Typewriter Text}%{Consolas}

If you want to compile your document time to time with lualatex or with pdflatex without changing preamble, you can use ifluatex package. Typical preamble for this purpose can looks like:

%%============================ Compiler Directives =======================%%
%%                                                                        %%
% !TeX program = lualatex                                   
% !TeX encoding = utf8
% !TeX spellcheck = english
%%                                                                        %%
%%============================== Document Class ==========================%%
%%                                                                        %%
\documentclass[14pt]{article}
\usepackage{ifluatex}
%%                                                                        %%
%%========================================================================%%

\ifluatex 
    \usepackage{fontspec}
    \setsansfont{CMU Sans Serif}%{Arial}
    \setmainfont{CMU Serif}%{Times New Roman}
    \setmonofont{CMU Typewriter Text}%{Consolas}
    \defaultfontfeatures{Ligatures={TeX}}
\else
    \usepackage[utf8]{inputenc}
    \usepackage[T2A,T1]{fontenc}
\fi

\usepackage[english]{babel}

\begin{document}



\end{document}

Answer 2

No, Luatex does not require using the fontenc package.

Answer 3

I still like to use 8 bit fonts for IPA (T3 encoding) and non-math Greek (LGR encoding)

I use them via the "substitutefont" package, and I believe that still requires that fontenc be loaded.

Anyway one thing I noticed is that if you load fontenc after fontspec then things break so if you do use fontenc, load it before fontspec.

Loading it before fontspec doesn't seem to harm anything.

EDIT:

I did a test. When loading fontenc after fontspec stuff, as long as TU is last specified encoding, things work. Take away the TU in this code and you'll see how it breaks.

\documentclass[letterpaper, fontsize=14pt]{scrbook}
\usepackage{fontspec}
\defaultfontfeatures{
  Ligatures = TeX,
  Extension = .ttf}
\setmainfont
  [ UprightFont = *-Regular ,
    ItalicFont  = *-Italic ,
    BoldFont    = *-Medium ,
    BoldItalicFont = *-MediumItalic ]
  {ClearSans}
\setsansfont
  [ UprightFont = *-Regular ,
    ItalicFont  = *-Italic ,
    BoldFont    = *-Bold ,
    BoldItalicFont = *-BoldItalic ]
  {ClearSans}
\usepackage[LGR,T1,TU]{fontenc}
\begin{document}
\chapter{Chapter One}
This is content.
\section{Section One}
This is more content.
\end{document}