fontname: "serif" resolved to: (PangoCairoFcFont) "EB Garamond, 08 Regular" /usr/share/fonts/opentype/ebgaramond/EBGaramond08-Regular.otf
which is the same as what I get for the solution with fontname defined for a node directly. But if possible, Iād like a solution where I wouldnāt need to specify the font at all when using Graphviz (neither in the graph, nor in the command). It would be nice if Graphviz had a configuration file I could put in my home directory, but I couldnāt find any mention of it.
Yes, it should have been dot -Nfontname=serif -Tpng ...
(by the way, the most recent release of Graphviz accepts dot -Afontname=serif -Tpng ... to set the default for nodes, edges, and graphs)
Unfortunately, there is no config file for Graphviz.
But you could define a shell alias like: alias dot=ādot -Afontname=serifā
Thank you for the alias suggestion. I didnāt think about it, Iām not used to aliases. Two impediments come to my mind (not of Graphvizās nature). One, I should make an alias for every Graphviz command (I might use any of them). Two, aliases should make my commands always less portable across different shells. If I make an alias for Bash, it wonāt be used in Dash. And even if I managed to make it work for both, one day I might use another shell in which it wouldnāt work. Both these impediments are to overcome, but still.
But I wonder, why shouldnāt Graphviz use settings in ~/.config/fontconfig/fonts.conf by default? I donāt know fontconfig, is there any technical reason?
PS. When I think about it, setting fontname to serif should tell Graphviz to use a serif font. But mind we, there is selected a serif DejaVu version anyway. So itās like Graphviz understand setting this attribute as an indication not exactly to use a serif font, but to read the configuration in fonts.conf. Would you agree?
Long, long, long ago, people on the internet said to try using ~/.fonts.conf instead
Overall, this seems like a fontconfig question; graphviz is just above it in the stack, but doesnāt have any knowledge of how fontconfig customization works.
Stephen, if you mean Graphviz would work with ~/.fonts.conf, then no, it doesnāt. I did cp ~/.config/fontconfig/fonts.conf ~/.fonts.conf and the output still contains āDejaVuā, not āGaramondā. (And just to note that Iām aware of it, freedesktop.org says here that itās deprecated.)
And Iām not sure whether this is a fontconfig question. As I said, from what I can see, it is fontname, Graphvizās attribute, that causes it to use the configuration in ~/.config/fontconfig/fonts.conf.
Iāve looked into this , and learned a few things.
Until running āfc-match serifā showed the binding you expect (EB Garamond?), this doesnāt seem like a graphviz issue. (pango uses fontconfig to find fonts.)
One problem is to figure out where to put user config files for fontconfig. On this computer, a MacBook, a lot of fontconfig customization files live in /opt/homebrew/etc/fonts/conf.d Sadly, 50-user.conf shows that loading $HOME/.config/fontconfig/conf.d is commented out, but <include ignore_missing="yes" deprecated="yes">~/.fonts.conf</include> lives on, which you can verify pretty easily. For example, drop an invalid XML tag into the user config file - fc-match will complain. (One an always edit 50-user.conf to try to get ~/.config/fontconfig working if thatās important.)
Second problem is to figure out how to write an override for <famlly>serif</family>. Iām stumped. My initial attempts failed. No matter what I wrote in ~/.fonts,config on this computer all I can get is:
At first that seems weird, but this definition is found in /opt/homebrew/etc/fonts/conf.d/65-nonlatin.conf.default so may be legit?
According to the README in /opt/homebrew/etc/fonts/conf.d my definitions should be read earlier and override the 65 prefix config, but Iām out of ideas here. Iāve tried about half a dozen ways of writing an override in ~/.fonts.config and none of them work.
which is indeed what I expect. So does it suggest a problem on the Graphvizās part or not, Iām not sure?
Just so we can compare, my /etc/fonts/conf.d/50-user.conf is
<?xml version="1.0"?>
<!DOCTYPE fontconfig SYSTEM "fonts.dtd">
<fontconfig>
<its:rules xmlns:its="http://www.w3.org/2005/11/its" version="1.0">
<its:translateRule translate="no" selector="/fontconfig/*[not(self::description)]"/>
</its:rules>
<description>Load per-user customization files</description>
<!--
Load per-user customization files where stored on XDG Base Directory
specification compliant places. it should be usually:
$HOME/.config/fontconfig/conf.d
$HOME/.config/fontconfig/fonts.conf
-->
<include ignore_missing="yes" prefix="xdg">fontconfig/conf.d</include>
<include ignore_missing="yes" prefix="xdg">fontconfig/fonts.conf</include>
<!-- the following elements will be removed in the future -->
<include ignore_missing="yes" deprecated="yes">~/.fonts.conf.d</include>
<include ignore_missing="yes" deprecated="yes">~/.fonts.conf</include>
</fontconfig>
Have you used the correct file? It should be ~/.fonts.conf, not ~/.fonts.config.
The only other thing I can contribute is that graphviz might specify Times-Roman or Times, not Serif unless some graphviz driver rewrites/overrides. The code is the most reliable documentation for details at that level
So did you succeed in overwriting the selection of the Hiragino font, or not?
Then, what does Graphviz specify, and where? Iām not accustomed to the codeā¦ (I might try to get! But it would certainly take time. The closest I can find is DEFAULT_FONTNAME Ā· Search Ā· GitLab)
One thing came to my mind to clear the picture, to do (in Bash)
for string in Times-Roman TimesRoman 'Times Roman'
do fc-match "$string"
done
which is different both from fc-match serif (DejaVu), Graphviz without fontname (DejaVu), and Graphviz with fontname (EB Garamond). But really, I donāt know which one I should expect to be the closest match.
Itās not a good situation, because thereās been a lot of work by different people, some long retired or moved away, on font binding and rendering over the years. Also because graphviz is intended to work with multiple conflicting or overlapping back end graphics systems with the goal of 100% compatibility. In primordial times graphviz was Postscript fonts with built in font tables. Huge step forward with freetype, fontconfig, libgd. Patches to smooth over differences with Windows. Another huge step with cairo pango, probably with some extensions . Later, native MacOS quartz drivers. With some driver selections, font sizing is done in one system (e.g. cairo pango) and rendering in another system (e.g. native SVG renderer). Some of the relevant code, e.g. hardwiring of default fonts, is in graphviz/lib/common/const.h and thereabouts. Other code found in graphviz/plugin. It is dismaying to see how often font names and translations are wired into arbitrary code.
Hereās a useful piece of information: on this computer, when I run dot on digraph G { a } the API call to pango_font_description_from_string in libpango.dylib passes the string argument
āTimes New Roman, REGULARā
This probably comes from line 111 of pango/gvgetfontlist_pango.c
Also I learned you can set FC_DEBUG to get more output, e.g. FC_DEBUG=1024 fc-match Serif shows what config files as being processed; FC_DEBUG=65535 seemed like it might have the potential to turn on a lot of messages. Well, er, we should have read this first: Ubuntu Manpage: fonts.conf - Font configuration files
Thank you, I will address your posts later. For now I just wanted to correct a statement from my last post. Writing
(ā¦) which is different both from fc-match serif (DejaVu), Graphviz without fontname (DejaVu), and Graphviz with fontname (EB Garamond)
I meant that only the first line (i.e. NimbusRoman-Regular.otf: "Nimbus Roman" "Regular") mentions a different font than in the quote. The two other lines of course mention the same font as in the quote (i.e. DejaVu).
OK, to be able to proceed with what I have found out, from now on Iām going to assume that itās true that I have built Graphviz with fontconfig support. If you can, please tell me whether my test above can prove it, or if it canāt, how I should test it properly.
I read fonts-conf (to be fair, I did read it the past, but only partially). I donāt understand everything yet, so should there arise a need to make use of information it contains, Iāll probably need to read again relevant parts.
I think Iām starting to imagine how this could be a āfontconfig questionā (that is, regardless of whether itās true, thatās yet to verify). I still donāt know how Graphviz works in this regard, though, so please correct me if Iāll be wrong.
I havenāt found any direct information how Graphviz should behave having no fontname defined (if thereās none indeed, maybe it could be added somewhere?). Iāve found only two related passages. One is in Font FAQ | Graphviz, and reads
[u]nder fontconfig, fontnames are family names, which fontconfig matches to the closest font it finds.
I understand it to suggest that fontconfig receives fontnameās value as is (otherwise, I expect there a description of how it be changed).
I understand it to suggest that if fontname isnāt given a value by the user, itās given a value of Times-Roman. That in turn should suggest that this attribute is used for something, and this āsomethingā might be passing its value to fontconfig. Of course, under the hood there may be more happening to this value.
should involve Graphvizās passing the string Times-Roman to fontconfig,
and that fontconfig should match it in the same way as with fc-match,
then
fc-match Times-Roman
should match DejaVu, that is, the same font as the pipeline in point 1 matches. Thatās not the case, though. Instead (what I have already showed in an earlier post) it gives
NimbusRoman-Regular.otf: "Nimbus Roman" "Regular"
Iāll take a look into the code now, maybe Iāll find some clues (but rather not).
How do you get the API calls?
To summarize, the goal is now to find what exact pattern fontconfig receives from Graphviz if there is no fontname specified. (Maybe also what it receives when fontname is specified, just to verify.) Then, assuming this be expected from the Graphvizās point of view, and the way it be matched be expected from the fontconfigās point of view, Iāll just make a rule in my fonts.conf so that this pattern be treated the same as the pattern serif, and my problem will be solved (and I can try to help you, Stephen, if you are still confused about fontconfig). If either assumption turned out to be false, probably Iād want to delve into this.
Update. Iām looking at the code and starting to suspect Graphviz doesnāt call fontconfig directly. In Font FAQ | Graphviz we read that
[t]ext layout is performed by pango, which accepts text and computes a layout with metrics that determine node sizes
so maybe itās Pango that does this instead? Graphviz give it text, Pango call fontconfig, then return mentioned ālayoutā. It would match the fact that you, Stephen, has pointed me to the function pango_font_description_from_string (and mean I have taken the longer route to get that)ā¦
Right, looks like thatās proof. Of course, pango requires fontconfig.
Itās unfortunate some of the build documentation is from an earlier era when the core drivers (like graphviz native PostScript and SVG) were written so they could be self-contained, but probably for a long time we have not considered that or tested if that works; pangoās needed for internationalization, anyway.
The -v command line option shows some runtime messages related to font binding, too.
I tried just now, and agree that ~/.fonts.conf (or whatever is the path where fontconfig is running) seems to have no effect on the binding that fontconfig makes in graphviz. The following verbose message confirms this
fontname: āTimes-Romanā resolved to: (ps:pango Times New Roman, REGULAR) (PangoCairoCoreTextFont) āTimes New Roman, 14ā
though fc-match Times-Roman on my computer is easily overridden to any other local font.
Sorry I havenāt been able to shed any light on this.
