Trials and Tribulations: How to find correct font names for Pandoc's use with LuaLaTeX?

Note: the following instructions were tested on Mac OSX. They should work on Linux too. For Windows you'll have to adapt them as needed.

LuaLaTeX makes it easy to use any font installed on your system when using pandoc to generate PDFs from Markdown source text.

Really easy? Yes... but only if you know how to specify a font name that LuaLaTeX actually understands!

Consider this: I was interested in all variations of my newly installed FOSS Adobe Source Code Pro fonts. They are said to have a really good coverage of box drawing characters, and I wanted to see that by letting pandoc --latex-engine=lualatex convert the following code block sample (which I copied from here) to PDF. This code box is part of my Markdown file 'fun-with-box-drawing.md':

        ┌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┐
        ┆Part of    ░▒▓▓▓▓┆
        ┆this stroked ░▒▓▓┆     ████████████▒
        ┆box is shaded.░▒▓┆     █████OK█████▓
        └╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌┘     ████████████▓
   ╔═══════════════╗            ▒▓▓▓▓▓▓▓▓▓▓▓▓
   ║Here are some  ║
   ║block elements ║ ┌───────────┐
   ║within a box.  ║ │ ▏▏▏▏▏▏▏ ▁ │
   ╠═══════════════╣ │ ▎▎▎▎▎▎ ▂▁ │
   ╙────┰─────┰────╜ │ ▍▍▍▍▍ ▃▂▁ │
        ┃     ┗━━━━━━┥ ▌▌▌▌ ▄▃▂▁ │
        ┃ → → → → → →│ ▋▋▋ ▅▄▃▂▁ │
        ┃ → → → → → →│ ▊▊ ▆▅▄▃▂▁ │
        ┗━━━━━━━━━━━━┥ ▉ ▇▆▅▄▃▂▁ │
                     │ ██▇▆▅▄▃▂▁ │
                     └───────────┘

Question: Which fontname to use?

Now what is a valid font name that can be given so that LuaLaTeX actually finds it? The filenames of my installed 'Source Code' fonts are these:

kp@mbp:~> ls -1 /Library/Fonts/SourceCodePro-*
 /Library/Fonts/SourceCodePro-Black.ttf
 /Library/Fonts/SourceCodePro-Bold.ttf
 /Library/Fonts/SourceCodePro-ExtraLight.ttf
 /Library/Fonts/SourceCodePro-Light.ttf
 /Library/Fonts/SourceCodePro-Regular.ttf
 /Library/Fonts/SourceCodePro-Semibold.ttf

I expected that adding -V monofont=SourceCodePro-Light to the Pandoc command line would work. It didn't. Next, I tried -V monofont=SourceCodePro-Light.ttf. Still no dice!

Then I tried to find out to the PostScript name as stored inside the font file itself. This is because a font's filename frequently does not match the PostScript name:

kp@mbp:> otfinfo -i /Library/Fonts/SourceCodePro-Light.ttf | head -n 17
 Family:              Source Code Pro Light
 Subfamily:           Regular
 Full name:           Source Code Pro Light
 PostScript name:     SourceCodePro-Light
 Preferred family:    Source Code Pro
 Preferred subfamily: Light
 Version:             Version 1.010;PS Version 1.000;hotconv 1.0.70;makeotf.lib2.5.5900
 Unique ID:           1.010;ADBE;SourceCodePro-Light;ADOBE
 Designer:            Paul D. Hunt
 Manufacturer:        Adobe Systems Incorporated
 Vendor URL:          http://www.adobe.com/type
 Trademark:           Source is a trademark of Adobe Systems Incorporated in the United States and/or other countries.
 Copyright:           Copyright 2010, 2012 Adobe Systems Incorporated. All Rights Reserved.
 License URL:         http://www.adobe.com/type/legal.html
 License Description: Copyright 2010, 2012 Adobe Systems Incorporated (http://www.adobe.com/), with Reserved Font Name 'Source'.
                      All Rights Reserved. Source is a trademark of Adobe Systems Incorporated in the United States and/or other countries.

 This Font Software is licensed under the SIL Open Font License, Version 1.1.

Hmmm... in this case it matched. I had tried the name SourceCodePro-Light already. For completeness, despite my extremely low expectation in this case, I also tried -V monofont="Source Code Pro Light". After all, otfinfo -i had suggested this as being the "Full name" of the font in question... Guess what?

Next, I tried to employ FontConfig's fc-list command to see what other fancy font names were available:

kp@mbp:~> fc-list | grep -i source | grep -i code
 /Library/Fonts/SourceCodePro-Black.ttf: Source Code Pro,Source Code Pro Black:style=Black,Regular
 /Library/Fonts/SourceCodePro-Light.ttf: Source Code Pro,Source Code Pro Light:style=Light,Regular
 /Library/Fonts/SourceCodePro-ExtraLight.ttf: Source Code Pro,Source Code Pro ExtraLight:style=ExtraLight,Regular
 /Library/Fonts/SourceCodePro-Semibold.ttf: Source Code Pro,Source Code Pro Semibold:style=Semibold,Regular
 /Library/Fonts/SourceCodePro-Bold.ttf: Source Code Pro:style=Bold
 /Library/Fonts/SourceCodePro-Regular.ttf: Source Code Pro:style=Regular

So fc-list didn't come up with anything different than otfinfo already had.

What now? Some search-engineing brought me a step closer to the solution.

Solution

Three years ago, TeXExchange users Ulrike Fischer and topskip came up with a shell script that prints a complete list of font names that may be used with LuaLaTeX.

Unfortunately the script had stopped working with newer versions of LuaLaTeX (such as is included in TeXLive 2014).

I updated Ulrike's and topskip's script to work with TeXLive 2014:

#!/usr/bin/env texlua

kpse.set_program_name("listluatexfonts")

cachefile  = kpse.expand_var("$TEXMFVAR")  .. "/luatex-cache/generic/names/luaotfload-names.luc"
fontlist = dofile(cachefile)
assert(fontlist,"Could not load font name database")

local tmp = {}

for _,font in ipairs(fontlist.mappings) do
  tmp[#tmp + 1] = font.fontname
end
table.sort(tmp)

for _,fontname in ipairs(tmp) do
  print(fontname)
end

Copy above code, save it as listluatexfonts somewhere on your $PATH and make it executable (chmod a+x listluatexfonts).

If you have recently installed new fonts (or if you never did run a LuaLaTeX command before), then run this command first to update the font cache available to LuaLaTeX:

luaotfload-tool -u -vvv

This will generate an updated cache of font names as luaotfload-names.luc in a path where it is found and can be used by LuaLaTeX.

kp@mbp:~> luaotfload-tool -u -vvv
 luaotfload | util : Setting log level
 luaotfload | util : Task completed successfully
 luaotfload | db : Updating the font names database.
 luaotfload | db : Font names database loaded
 luaotfload | db : Loading took 18 ms.
 luaotfload | db : Blacklisting 8 files and directories.
 luaotfload | db : Whitelisting 0 files.
 luaotfload | db : Scanning TEXMF fonts...
 luaotfload | db : Initiating scan of 401 directories.
 luaotfload | db : Scanned 1496 files, 0 new.
 luaotfload | db : Scanning OS fonts...
 luaotfload | db : Searching in static system directories...
 luaotfload | db : Scanned 610 files, 0 new.
 luaotfload | db : Scanned 0 font files; 0 new entries.
 luaotfload | db : Creating filename map.
 luaotfload | db : Analyzing families, sizes, and styles.
 luaotfload | db : Ordering design sizes.
 luaotfload | db : Rebuilt in 649 ms.
 luaotfload | db : Font index saved at ...
 luaotfload | db : Gzip: /Users/kp/.texlive2014/texmf-var/luatex-cache/generic/names/luaotfload-names.lua.gz
 luaotfload | db : Byte: /Users/kp/.texlive2014/texmf-var/luatex-cache/generic/names/luaotfload-names.luc
 luaotfload | cache : Lookup cache saved.
 luaotfload | cache : Lookup cache emptied.
 luaotfload | db : Fonts in the database: 1591
 luaotfload | util : Task completed successfully

Now run the above script:

./listluatexfonts

I did it as listluatexfonts | grep -i source and saw this list:

sourcecodeproblack
sourcecodeprobold
sourcecodeproextralight
sourcecodeprolight
sourcecodepromedium
sourcecodeproregular
sourcecodeprosemibold

Uh-huh!

Now my Pandoc command also worked and it produced the outputs I wanted:

 for font in $(listluatexfonts | grep -i source | grep -i code); do
   pandoc                                          \
      --highlight-style=espresso                   \
      --latex-engine=lualatex                      \
       -V monofont="${font}"                       \
       -o fun-with-box-drawing---using-${font}.pdf \
        box-drawing-fun-with-adobe-source-code-pro-fonts.md
 done

It turned out that the box drawing I had used wasn't the best to really highlight the specific differences between the various Source Code font faces. A better one is this:

 +×△▲△©━┭╱═══╲┮━©△▲△×+
╔══╩╬╩╡÷╱← 0 →╲÷╞╩╬╩══╗
╚═╗╭╫╮ợ╱┅┅┓┅┏┅┅╲ọ╭╫╮╔═╝
╒═╝╎║┊╱X╭─────╮X╲┊║╎╚═╕
││┐╎║┊╳╓╖ BOX ╥╖╳┊║╎┌││
└││╎║╰─╨╠═════╣╨─╯║╎││┘
│└│╞╝╔╗▞╟╱╲╳╱╲╢▚╔╗╚╡│┘│
╰─╥┧Y║║▞ ┳┳┳┳┳ ▚║║Y┟╥─╯
☐┌╢┗┛╠║▞┍╇╇Ø╇╇┑▚║╣┗┛╟┐☑
┃!╚══╝┎┐│━┵┼┶━│┌┒╚══╝!┃
┃└┐┼┃│┃╷└─────┘╷┃│┃┼┌┘┃
┃♪╿│▼▽┃╰───*───╯┃▽▼│╿√┃
╚╦╧╰─>┡ DRAWING ┩<─╯╧╦╝
╶I┉┉┉┭└┄┄┄┄┄┄┄┄┄┘┮┉┉┉I╴
╭──┬─┴/ SOU┬RCE \┴─┬──╮
┢━━┷━━━━╸CO┼DE╺━━━━┷━━┪
━━━┻╾╮←(┏┑PRO┍┓)→╭╼┻━━━
░▒▓▌─╯┯━┷└───┘┷━┯╰─▐▓▒░
z─────┘────¡────└─────z

Here is a side-by-side screenshot of the resulting PDFs produced by pandoc for Source Code Black and ExtraLight font faces: