%% This is part of the OpTeX project, see http://petr.olsak.net/optex \_codedecl \fontfam {Fonts selection system <2023-06-16>} % preloaded in format \_doc ----------------------------- The main principle of the Font Selection System is: run one or more modifiers followed by \^`\fontsel`. Modifiers save data and \^`\fontsel` selects the font considering saved data. Each basic variant selector \`\rm`, \`\bf`, \`\it`, \`\bi`, and \`\tt` runs internal variant modifier \`\_fmodrm`, \`\_fmodbf`, \`\_fmodit`, \`\_fmodbi` and \`\_fmodtt`. These modifiers save their data to the \`\_famv` macro which is `rm` or `bf` or `it` or `bi` or `tt`. The \`\currvar` selector is \^`\fontsel` by default, but variant selectors declared by \^`\famvardef` change it. \_cod ----------------------------- \_def\_famv{rm} % default value \_protected\_def \_fmodrm {\_def\_famv{rm}} \_protected\_def \_fmodbf {\_def\_famv{bf}} \_protected\_def \_fmodit {\_def\_famv{it}} \_protected\_def \_fmodbi {\_def\_famv{bi}} \_protected\_def \_fmodtt {\_def\_famv{tt}} \_protected\_def \_rm {\_fmodrm \_fontsel \_marm} \_protected\_def \_bf {\_fmodbf \_fontsel \_mabf} \_protected\_def \_it {\_fmodit \_fontsel \_mait} \_protected\_def \_bi {\_fmodbi \_fontsel \_mabi} \_protected\_def \_tt {\_fmodtt \_fontsel \_matt} \_protected\_def \_currvar {\_fontsel} \_protected\_def \currvar{\_currvar} \_public \rm \bf \it \bi \tt ; \_doc ----------------------------- The \`\fontsel` creates the in the format `\_ten` and loads the font associated to the . The loading is done by: \begitems \style a * `\letfont = \savedswitch \_sizespec` * `\font = \fontnamegen \_sizespec` \enditems The a) variant is used when \~`\_fontnamegen` isn't defined, i.e.\ \^`\fontfam` wasn't used: only basic variant and \^`\_sizespec` is taken into account. The b) variant is processed when \^`\fontfam` was used: all data saved by all font modifiers are used during expansion of \^`\_fontnamegen`.\nl After the font is loaded, final job is done by \`\_fontselA```. \_cod ----------------------------- \_protected\_def \_fontsel {% \_ifx\_fontnamegen\_undefined % \fontfam was not used \_ea\_let \_ea\_tmpf \_csname _ten\_famv\_endcsname \_ea\_fontlet \_csname _ten\_xfamv\_endcsname \_tmpf \_sizespec \_else % \fontfam is used \_ea\_font \_csname _ten\_xfamv\_endcsname {\_fontnamegen}\_sizespec \_fi \_relax \_ea \_fontselA \_csname _ten\_xfamv\_endcsname } \_def\_fontselA #1{% \_protected\_def \_currvar {\_fontsel}% default value of \_currvar \_logfont #1% font selecting should be logged. \_setwsp #1% wordspace setting \_fontloaded #1% initial settings if font is loaded firstly #1% select the font } \_def \_logfont #1{} \_def \_xfamv {\_famv} \_public \fontsel ; \_doc ----------------------------- If a font is loaded by macros \^`\fontsel` or \^`\resizethefont` then the \`\_fontloaded``` is called immediately after it. If the font is loaded first then its `\skewchar` is equal to $-1$. We run \`\_newfontloaded``` and set `\skewchar=-2` in this case. A user can define a `\_newfontloaded` macro. We are sure that `\_newfontloaded` macro is called only once for each instance of the font given by its name, OTF features and size specification. The `\skewchar` value is globally saved to the font (like `\fontdimen`). If it is used in math typesetting then it is set to a positive value.\nl The `\_newfontloaded` should be defined for micro-typographic configuration of fonts, for example. The `mte.opm` package uses it. See also \ulink[http://petr.olsak.net/optex/optex-tricks.html\#fontexpand]{\OpTeX/ trick 0058}. \_cod ----------------------------- \_def\_fontloaded #1{\_ifnum\_skewchar#1=-1 \_skewchar#1=-2 \_newfontloaded#1\_fi} \_def\_newfontloaded #1{} \_doc ----------------------------- \`\_ttunifont` is default font for \^`\tt` variant when \^`\initunifonts` is declared. User can re-define it or use \^`\famvardef``\tt`. The \`\_unifmodtt` macro is used instead \^`\_fmodtt` after \^`\initunifonts`. It ignores the loading part of the following \^`\fontsel` and do loading itself. \_cod ----------------------------- \_def\_ttunifont{[lmmono10-regular]:\_fontfeatures-tlig;} \_def\_unifmodtt\_fontsel{% ignore following \_fontsel \_ea\_font \_csname _ten\_ttfamv\_endcsname {\_ttunifont}\_sizespec \_relax \_ea\_fontselA \_csname _ten\_ttfamv\_endcsname \_def \_currvar{\_tt}% } \_def\_ttfamv{tt} \_doc ---------------------------- A large part of the Font Selection System was re-implemented in Feb. 2022. We want to keep backward compatibility: \_cod ---------------------------- \_def \_tryloadrm\_tenrm {\_fmodrm \_fontsel} \_def \_tryloadbf\_tenbf {\_fmodbf \_fontsel} \_def \_tryloadit\_tenit {\_fmodit \_fontsel} \_def \_tryloadbi\_tenbi {\_fmodbi \_fontsel} \_def \_tryloadtt\_tentt {\_fmodtt \_fontsel} \_def \_reloading {} \_doc ----------------------------- The \`\_famdecl` `[] \ {} {} {} {}`\nl `{} {\def`\^`\_fontnamegen``{}}` runs \^`\initunifonts`, then checks if `\` is defined. If it is true, then closes the file by `\endinput`. Else it defines `\` and saves it to the internal `\_f::main.fam` command. The macro \`\_initfontfamily` needs it. The \`\_currfamily` is set to the `` because the following \^`\moddef` commands need to be in the right font family context. The `\_currfamily` is set to the `` by the `\` too, because `\` must set the right font family context. The font family context is given by the current `\_currfamily` value and by the current meaning of the \^`\_fontnamegen` macro. The \`\_mathfaminfo` is saved for usage in the catalog. \_cod ----------------------------- \_def\_famdecl [#1]#2#3#4#5#6#7#8{% \_initunifonts \_unichars \_uniaccents \_unless\_ifcsname _f:\_csstring#2:main.fam\_endcsname \_isfont{#7}\_iffalse \_opwarning{Family [#1] skipped, font "#7" not found}\_endinput \_ifcsname _fams:\_famfile\_endcsname \_famsubstitute \_fi \_else \_edef\_currfamily {\_csstring #2}\_def\_mathfaminfo{#6}% \_wterm {FONT: [#1] -- \_string#2 \_detokenize{(#3)^^J mods:{#4} vars:{#5} math:{#6}}}% \_unless \_ifx #2\_undefined \_opwarning{\_string#2 is redefined by \_string\_famdecl\_space[#1]}\_fi \_protected\_edef#2{\_def\_noexpand\_currfamily{\_csstring #2}\_unexpanded{#8\_resetfam}}% \_ea \_let \_csname _f:\_currfamily:main.fam\_endcsname =#2% \_fi \_else \_csname _f:\_csstring#2:main.fam\_endcsname \_rm \_endinput \_empty\_fi } \_def\_initfontfamily{% \_csname _f:\_currfamily:main.fam\_endcsname \_rm } \_doc ----------------------------- \`\_fvars` ` ` saves data for usage by the `\_currV` macro. If a template is only dot then previous template is used (it can be used if the font family doesn't dispose with all standard variants). \nl \`\_currV` expands to a template declared by `\_fvars` depending on the ``. Usable only of standard four variants. Next variants can be declared by the \^`\famvardef` macro. \nl \`\_fsetV` `=,...,=` expands to `\def\_V{}` in the loop. \nl \`\_onlyif` `=,...,: {}` runs only if the `\_V` is defined as `` or `` or ... or ``. \nl \`\_prepcommalist` `ab,{},cd,\_fin,` expands to `ab,,cd,` (auxiliary macro used in `\_onlyif`).\nl \`\_ffonum` is a shortcut for oldstyle digits font features used in font family files. You can do `\let\_ffonum=\ignoreit` if you don't want to set old digits together with `\caps`. \_cod ----------------------------- \_def\_fvars #1 #2 #3 #4 {% \_sdef{_fvar:rm}{#1}% \_sdef{_fvar:bf}{#2}% \_ifx.#2\_slet{_fvar:bf}{_fvar:rm}\_fi \_sdef{_fvar:it}{#3}% \_ifx.#3\_slet{_fvar:it}{_fvar:rm}\_fi \_sdef{_fvar:bi}{#4}% \_ifx.#4\_slet{_fvar:bi}{_fvar:it}\_fi } \_def\_currV{\_trycs{_fvar:\_famv}{rm}} \_def\_V{ } \_def \_fsetV #1 {\_fsetVa #1,=,} \_def \_fsetVa #1=#2,{\_isempty{#1}\_iffalse \_ifx,#1\_else\_sdef{_#1V}{#2}\_ea\_ea\_ea\_fsetVa\_fi\_fi } \_def \_onlyif #1=#2:#3{% \_edef\_act{\_noexpand\_isinlist{,\_prepcommalist #2,\_fin,}{,\_cs{_#1V},}}\_act \_iftrue #3\_fi } \_def\_prepcommalist#1,{\_ifx\_fin#1\_empty\_else #1,\_ea\_prepcommalist\_fi} \_def\_ffonum {+onum;+pnum} \_doc ----------------------------- The \`\moddef` `\ {}` simply speaking does `\def\{}`, but we need to respect the family context. In fact, `\protected\def\_f::{}` is performed and the `\` is defined as \`\_famdepend``\{_f:\_currfamily:}`. It expands to `\_f:\_currfamily:` value if it is defined or it prints the warning. When the `\_currfamily` value is changed then we can declare the same `\` with a different meaning. \`\_setnewmeaning` `=\_tmpa ` does exactly `\_let =\_tmpa` but warning is printed if is defined already and it is not a variant selector or font modifier. \`\_addtomodlist` `` adds given modifier to \`\_modlist` macro. This list is used after \^`\resetmod` when a new family is selected by a family selector, see \`\_resetfam` macro. This allows reinitializing the same current modifiers in the font context after the family is changed. \_cod ----------------------------- \_def \_moddef #1#2{% \_edef\_tmp{\_csstring#1}% \_sdef{_f:\_currfamily:\_tmp}{\_addtomodlist#1#2}% \_protected \_edef \_tmpa{\_noexpand\_famdepend\_noexpand#1{_f:\_noexpand\_currfamily:\_tmp}}% \_setnewmeaning #1=\_tmpa \moddef } \_protected \_def\_resetmod {\_cs{_f:\_currfamily:resetmod}} % private variant of \resetmod \_def \_resetfam{% \_def\_addtomodlist##1{}\_resetmod \_edef \_modlist{\_ea}\_modlist \_let\_addtomodlist=\_addtomodlistb \_ifcsname _f:\_currfamily:\_ea\_csstring \_currvar \_endcsname \_else \_ea\_ifx\_currvar\_tt \_else \_def\_currvar{\_fontsel}\_fi \_fi % corrected \_currvar in the new family } \_def \_currfamily{} % default current family is empty \_def \_modlist{} % list of currently used modifiers \_def \_addtomodlist#1{\_addto\_modlist#1} \_let \_addtomodlistb=\_addtomodlist \_def\_famdepend#1#2{\_ifcsname#2\_endcsname \_csname#2\_ea\_endcsname \_else \_ifx\_addtomodlist\_addtomodlistb \_opwarning{\_string#1 is undeclared in family "\_currfamily", ignored}\_fi\_fi } \_def\_setnewmeaning #1=\_tmpa#2{% \_ifx #1\_undefined \_else \_ifx #1\_tmpa \_else \_opwarning{\_string#1 is redefined by \_string#2}% \_fi\_fi \_let#1=\_tmpa } \_public \moddef ; \_doc ----------------------------- \`\fontdef` ` {}` does: \begtt \catcode`\<=13 \begingroup \ea\endgroup \ea\let \ea \the\font \endtt It means that font modifiers used in are applied in the group and the resulting selected font (current at the end of the group) is set to the . We want to declare in its real name directly by `\font` primitive in order to save this name for reporting later (in overfull messages, for example). This is the reason why \`\_xfamv` and \`\_ttfamv` are re-defined locally here. They have precedence when \^`\fontsel` constructs the name. \_cod ----------------------------- \_protected\_def \_fontdef #1#2{\_begingroup \_edef\_xfamv{\_csstring#1}\_let\_ttfamv\_xfamv #2% \_ea\_endgroup\_ea \_let\_ea #1\_the\_font } \_public \fontdef ; \_doc ----------------------------- The \`\famvardef` `\xxx {}` does, roughly speaking: \begtt \catcode`\<=13 \def \xxx {{\ea}\the\font \def\_currvar{\xxx}} \endtt but the macro `\xxx` is declared as family-dependent. It is analogically as in `\moddef`. The `\xxx` is defined as `\_famdepend\xxx{_f:\_currfamily:xxx}` and `\_f::xxx` is defined as mentioned.\nl `\famvardef\tt` behaves somewhat differently: it defines internal version `\_tt` (it is used in \^`\_ttfont` and \^`\_urlfont`) and set `\tt` to the same meaning. \_cod ----------------------------- \_protected\_def \_famvardef #1#2{% \_sdef{_f:\_currfamily:\_csstring#1}% {{\_edef\_xfamv{\_csstring#1}\_let\_ttfamv\_xfamv #2\_ea}\_the\_font \_def\_currvar{#1}}% \_protected\_edef\_tmpa {% \_noexpand\_famdepend\_noexpand#1{_f:\_noexpand\_currfamily:\_csstring#1}}% \_ifx #1\tt \_protected\_def\_tt{{\_def\_xfamv{tt}#2\_ea}\_the\_font \_def\_currvar{\_tt}}% \_let\tt=\_tt \_else \_setnewmeaning #1=\_tmpa \famvardef \_fi } \_public \famvardef ; \_doc ----------------------------- The \`\fontfam` `[]` does: \begitems * Convert its parameter to lower case and without spaces, e.g.\ ``. * If the file `f-.opm` exists read it and finish. * Try to load user defined `fams-local.opm`. * If the `` is declared in `fams-local.opm` or `fams-ini.opm` read relevant file and finish. * Print the list of declared families. \enditems The `fams-local.opm` is read by the \`\_tryloadfamslocal` macro. It sets itself to `\_relax` because we need not load this file twice. The \`\_listfamnames` macro prints registered font families to the terminal and to the log file. \_cod ----------------------------- \_protected\_def \_fontfam [#1]{% \_lowercase{\_edef\_famname{\_ea\_removespaces \_expanded{#1} {} }}% \_isfile {f-\_famname.opm}\_iftrue \_edef\_famfile{f-\_famname}\_opinput {f-\_famname.opm}% \_else \_tryloadfamslocal \_edef\_famfile{\_trycs{_famf:\_famname}{}}% \_ifx\_famfile\_empty \_ifcsname _fams:f-\_famname \_endcsname \_edef\_famfile{f-\_famname}\_famsubstitute \_else \_listfamnames \_fi \_else \_opinput {\_famfile.opm}% \_fi\_empty\_fi } \_def\_tryloadfamslocal{% \_isfile {fams-local.opm}\_iftrue \_opinput {fams-local.opm}\_famfrom={}\_famsrc={}% \_fi \_let \_tryloadfamslocal=\_relax % need not to load fams-local.opm twice } \_def\_listfamnames {% \_wterm{===== List of font families ======} \_begingroup \_let\_famtext=\_wterm \_def\_faminfo [##1]##2##3##4{% \_wterm{ \_space\_noexpand\fontfam [##1] -- ##2}% \_let\_famalias=\_famaliasA}% \_opinput {fams-ini.opm}% \_isfile {fams-local.opm}\_iftrue \_opinput {fams-local.opm}\_fi \_message{^^J}% \_endgroup } \_def\_famaliasA{\_message{ \_space\_space\_space\_space -- alias:} \_def\_famalias[##1]{\_message{[##1]}}\_famalias } \_public \fontfam ; \_doc ----------------------------- \`\fontfamsub` `[][]` declares automatic substitution of by which is done when is not installed. I.e. if there is no `f-.opm` file or there is no regular font of the family installed. \`\_famsubstitute` is internal macro used in \^`\fontfam` and \^`\_famdecl` macros. It consumes the rest of the macro, runs \^`\nospacefuturelet` in order to do `\endinput` to the current `f-file` and runs \^`\fontfam` again. The table of such substutitions are saved in the macros `\_fams:`. \_cod ----------------------------- \_def \_fontfamsub [#1]#2[#3]{\_tryloadfamslocal \_lowercase{\_edef\_tmp{\_removespaces #1 {} }}% \_sxdef{_fams:\_trycs{_famf:\_tmp}{f-\_tmp}}{#3}% } \_def\_famsubstitute #1\_empty\_fi{\_fi\_fi\_fi \_wterm {FONT-SUB: \_famfile\_space -> [\_cs{_fams:\_famfile}]}% \_nospacefuturelet\_tmp\_famsubstituteA % we want to \endinput current f-file } \_def\_famsubstituteA{\_fontfam[\_cs{_fams:\_famfile}]} \_public \fontfamsub ; \_doc ----------------------------- When the `fams-ini.opm` or `fams-local.opm` files are read then we need to save only a mapping from family names or alias names to the font family file names. All other information is ignored in this case. But if these files are read by the `\_listfamnames` macro or when printing a catalog then more information is used and printed.\nl \`\_famtext` does nothing or prints the text on the terminal. \nl \`\_faminfo` `[] {} {} {}` does\nl `\_def \_famf: {}` (only if differs from `f-`) or prints information on the terminal. The data are used when printing the font catalog. \nl \`\_famalias` `[]` does `\def \_famf: {}` where `` is stored from the previous `\_faminfo` command. Or prints information on the terminal. \nl \`\_famfrom` declares type foundry or owner or designer of the font family. It can be used in `fams-ini.opm` or `fams-local.opm` and it is printed in the font catalog. \nl \`\_famsrc` declares the source, where is the font family from (used in `fams-ini.opm` and if the font isn't found when the fonts catalog is printed). \_cod ----------------------------- \_def\_famtext #1{} \_def\_faminfo [#1]#2#3#4{% \_lowercase{\_edef\_tmp{\_ea\_removespaces #1 {} }}% \_edef\_tmpa{f-\_tmp}\_def\_famfile{#3}% \_unless\_ifx\_tmpa\_famfile \_sdef{_famf:\_tmp}{#3}\_fi } \_def\_famalias [#1]{% \_lowercase{\_edef\_tmpa{\_ea\_removespaces #1 {} }}% \_sdef{_famf:\_tmpa\_ea}\_ea{\_famfile}% } \_newtoks\_famfrom \_newtoks\_famsrc \_input fams-ini.opm \_let\_famfile=\_undefined \_famfrom={} \_famsrc={} \_doc ----------------------------- When the \^`\fontfam``[catalog]` is used then the file `fonts-catalog.opm` is read. The macro \^`\_faminfo` is redefined here in order to print catalog samples of all declared modifiers/variant pairs. The user can declare different samples and different behavior of the catalog, see the end of catalog listing for more information. The default parameters \`\catalogsample`, \`\catalogmathsample`, \`\catalogonly`, \`\catalogexclude` and \`\catalognextfam` of the catalog are declared here. \_cod ----------------------------- \_newtoks \_catalogsample \_newtoks \_catalogmathsample \_newtoks \_catalogonly \_newtoks \_catalogexclude \_newtoks \_catalognextfam \_catalogsample={ABCDabcd Qsty fi fl áéíóúüů řžč ÁÉÍÓÚ ŘŽČ 0123456789} \_catalognextfam={\_bigskip} \_public \catalogonly \catalogexclude \catalogsample \catalogmathsample \catalognextfam ; \_doc ----------------------------- The font features are managed in the \`\_fontfeatures` macro. It expands to \begitems * \`\_defaultfontfeatures` -- used for each font, * \`\_ffadded` -- features added by \^`\setff`, * \`\_ffcolor` -- features added by \^`\setfontcolor` (this is obsolette) * \`\_ffletterspace` -- features added by \^`\setletterspace`, * \`\_ffwordspace` -- features added by \^`\setwordspace`. \enditems The macros \^`\_ffadded`, \^`\_ffcolor`, \^`\_ffletterspace`, \^`\_ffwordspace` are empty by default. \_cod ----------------------------- \_def \_fontfeatures{\_defaultfontfeatures\_ffadded\_ffcolor\_ffletterspace\_ffwordspace} \_def \_defaultfontfeatures {+tlig;} \_def \_ffadded{} \_def \_ffcolor{} \_def \_ffletterspace{} \_def \_ffwordspace{} \_doc ----------------------------- The \`\setff` `{}` adds next font features to \^`\_ffadded`. Usage \^`\setff{}` resets empty set of all \^`\_ffadded` features. \_cod ----------------------------- \_def \_setff #1{% \_ifx^#1^\_def\_ffadded{}\_else \_edef\_ffadded{\_ffadded #1;}\_fi } \_public \setff ; \_doc ----------------------------- \`\setletterspace` is based on the special font features provided by `luaotfload` package.\nl The \`\setwordspace` recalculates the `\fontdimen2,3,4` of the font using the \`\setwsp` macro which is used by the \^`\_fontselA` macro. It activates a dummy font feature `+Ws` too in order the font is reloded by the `\font` primitive (with independent `\fontdimen` registers). If the \^`\setwordspace` is used again to the same font then we need to reset `\fondimen` registers first. It is done by `\_sws:` macro which keeps the original values of the `\fontdimen`s.\nl \`\setfontcolor` is kept here only for backward compatibility but not recommended. Use real color switches and the \^`\transparency` instead. \_cod ----------------------------- \_def \_setfontcolor #1{% \_edef\_tmp{\_calculatefontcolor{#1}}% \_ifx\_tmp\_empty \_def\_ffcolor{}\_else \_edef\_ffcolor{color=\_tmp;}\_fi } \_def \_setletterspace #1{% \_if^#1^\_def\_ffletterspace{}\_else \_edef\_ffletterspace{letterspace=#1;}\_fi } \_def \_setwordspace #1{% \_if^#1^\_def\_setwsp##1{}\_def\_ffwordspace{}% \_else \_def\_setwsp{\_setwspA#1/}\_def\_ffwordspace{+Ws;}\_fi } \_def\_setwsp #1{} \_def\_setwspA #1{\_ifx/#1\_ea\_setwspB \_else\_afterfi{\_setwspC#1}\_fi} \_def\_setwspB #1/#2/#3/#4{% \_csname _sws:\_fontname#4\_endcsname \_relax \_ea\_xdef \_csname _sws:\_fontname#4\_endcsname {\_foreach 234\_do{\_fontdimen##1#4=\_the\_fontdimen##1#4}}% \_fontdimen2#4=#1\_fontdimen2#4% \_fontdimen3#4=#2\_fontdimen3#4\_fontdimen4#4=#3\_fontdimen4#4} \_def\_setwspC #1/{\_setwspB #1/#1/#1/} \_def\_calculatefontcolor#1{\_trycs{_fc:#1}{#1}} % you can define more smart macro ... \_sdef{_fc:red}{FF0000FF} \_sdef{_fc:green}{00FF00FF} \_sdef{_fc:blue}{0000FFFF} \_sdef{_fc:yellow}{FFFF00FF} \_sdef{_fc:cyan}{00FFFFFF} \_sdef{_fc:magenta}{FF00FFFF} \_sdef{_fc:white}{FFFFFFFF} \_sdef{_fc:grey}{00000080} \_sdef{_fc:lgrey}{00000025} \_sdef{_fc:black}{} % ... you can declare more colors... \_public \setfontcolor \setletterspace \setwordspace ; \_doc ----------------------------- \`\_regoptsizes` ` ? ` prepares data for using by the \`\_optname` `` macro. The data are saved to the `\_oz:` macro. When the `\_optname` is expanded then the data are scanned by the macro \`\_optnameA` `? `\code{<}`` in the loop.\nl \`\_optfontalias` `{ is undeclared in the current family" and nothing happens. But you can declare the same variant selector by \^`\famvardef` macro in the context of a new family. Then the same command may do different work depending on the current font family. Suppose that the selected font family provides the font modifier `\medium` for mediate weight of fonts. Then you can declare: \begtt \famvardef \mf {\medium\rm} \famvardef \mi {\medium\it} \endtt Now, you can use six independent variant selectors `\rm`, `\bf`, `\it`, `\bi`, `\mf` and `\mi` in the selected font family. A `\` can be written before `` in the `\famvardef` parameter. Then the `\` is declared in the current family but it can use fonts from another family represented by the `\`. When you are mixing fonts from more families then you probably run into a problem with incompatible ex-heights. This problem can be solved using \^`\setfontsize` and \^`\famvardef` macros: \begtt \fontfam[Heros] \fontfam[Termes] \def\exhcorr{\setfontsize{mag.88}} \famvardef\rmsans{\Heros\exhcorr\rm} \famvardef\itsans{\Heros\exhcorr\it} Compare ex-height of Termes \rmsans with Heros \rm and Termes. \endtt The variant selectors (declared by \~`\famvardef`) or font modifiers (declared by \~`\moddef`) are (typically) control sequences in the public namespace (`\mf`, `\caps`). They are most often declared in font family files and they are loaded by \^`\fontfam`. A conflict with such names in the public namespace can be here. For example: if `\mf` is defined by a user and then `\fontfam[Roboto]` is used then `\famvardef\mf` is performed for Roboto family and the original meaning of `\mf` is lost. But \OpTeX/ prints warning about it. There are two cases: \begtt \def\mf{Metafont} \fontfam[Roboto] % warning: "The \mf is redefined by \famvardef" is printed or \fontfam[Roboto] \def\mf{Metafont} % \mf variant selector redefined by user, we suppose that \mf % is used only in the meaning of "Metafont" in the document. \endtt \secc[tt] The `\tt` variant selector \^`\tt` is an additional special variant selector which is defined as \"select typewriter font independently of the current font family". By default, the typewriter font-face from LatinModern font family is used. The \^`\tt` variant selector is used in \OpTeX/ internal macros \^`\_ttfont` (verbatim texts) and \^`\_urlfont` (printing URL's). The behavior of \^`\tt` can be re-defined by \^`\famvardef`. For example: \begtt \fontfam[Cursor] \fontfam[Heros] \fontfam[Termes] \famvardef\tt{\Cursor\setff{-liga;-tlig}\rm} Test in Termes: {\tt text}. {\Heros\rm Test in Heros: {\tt text}}. Test in URL \url{http://something.org}. \endtt % You can see that \^`\tt` stay family independent. This is a special feature only for \^`\tt` selector. New definitions of \^`\_ttfont` and \^`\_urlfont` are done too. It is recommended to use `\setff{-liga;-tlig}` to suppress the ligatures in typewriter fonts. If Unicode math font is loaded then the `\tt` macro selects typewriter font-face in math mode too. This face is selected from used Unicode math font and it is independent of `\famvardef\tt` declaration. \secc[fontmacros] Font commands defined by `\def` Such font commands can be used as fonts selectors for titles, footnotes, citations, etc. Users can define them. The following example shows how to define a \"title-font selector". Titles are not only bigger but they are typically in the bold variant. When a user puts `{\it...}` into the title text then he/she expects bold italic here, no normal italic. You can remember the great song by John Lennon \"Let It Be" and define: \begtt \def\titlefont{\setfontsize{at14pt}\bf \let\it\bi} ... {\titlefont Title in bold 14pt font and {\it bold 14pt italics} too} \endtt \OpTeX/ defines similar internal commands \^`\_titfont`, \^`\_chapfont`, \^`\_secfont` and \^`\_seccfont`, see section~\ref[sections]. The commands \^`\typosize` and \^`\boldify` are used in these macros. They set the math fonts to given size too and they are defined in section~\ref[opmac-fonts]. \secc[setff] Modifying font features %---------------------------- Each OTF font provides \"font features". You can list these font features by `otfinfo -f font.otf`. For example, LinLibertine fonts provide `frac` font feature. If it is active then fractions like 1/2 are printed in a special form. The font features are part of the font context data. The macro \^`\setff` `{}` acts like family independent font modifier and prepares a new . You must use a variant selector in order to reinitialize the font with the new font feature. For example \^`\setff``{+frac}\rm` or \^`\setff``{+frac}`\^`\currvar`. You can declare a new variant selector too: \begtt \fontfam[LinLibertine] \famvardef \fraclig {\setff{+frac}\currvar} Compare 1/2 or 1/10 \fraclig to 1/2 or 1/10. \endtt If the used font does not support the given font feature then the font is reloaded without warning nor error, silently. The font feature is not activated. The `onum` font feature (old-style digits) is connected to `\caps` macro for Caps+SmallCaps variant in \OpTeX/ font family files. So you need not create a new modifier, just use `{\caps`\^`\currvar`` 012345}`. \secc[specff] Special font modifiers %--------------------------- Despite the font modifiers declared in the font family file (and dependent on the font family), we have following font modifiers (independent of font family): \begtt \catcode`\<=13 \setfontsize{} % sets the font size \setff{} % adds the font feature \setletterspace{} % sets letter spacing \setwordspace{} % modifies word spacing \endtt The \^`\setfontsize` command is described in the section \ref[setfontsize]. The \^`\setff` command was described in previous subsection. \^`\setletterspace` `{}` specifies the letter spacing of the font. The `` is a decimal number without unit. The unit is supposed as 1/100 of the font size. I.e. `2.5` means 0.25 pt when the font is at 10 pt size. The empty parameter `` means no letter spacing which is the default. \^`\setwordspace` `{}` scales the default interword space (defined in the font) and its stretching and shrinking parameters by given `` factor. For example `\setwordspace{2.5}` multiplies interword space by 2.5. \^`\setwordspace` can use different multiplication factors if its parameter is in the format `{///}`. For example, `\setwordspace{/1/2.5/1}` enlarges only stretching 2.5~times. You can use `\setff` with other font features provided by Lua\TeX/ and `luaotfload` package (see documentation of `loaotfload` package for more information): \begtt \setff{embolden=1.5}\rm % font is bolder because outline has nonzero width \setff{slant=0.2}\rm % font is slanted by a linear transformation \setff{extend=1.2}\rm % font is extended by a linear transformation. \setff{colr=yes}\rm % if the font includes colored characters, use colors \setff{upper}\rm % to uppercase (lower=lowecase) conversion at font level \setff{fallback=name}\rm % use fonts from a list given by name if missing chars \endtt Use font transformations `embolden`, `slant`, `extend` and \^`\setletterspace`, \^`\setwordspace` with care. The best setting of these values is the default setting in every font, of course. If you really need to set a different letter spacing then it is strongly recommended to add `\setff{-liga}` to disable ligatures. And setting a positive letter spacing probably needs to scale interword spacing too. All mentioned font modifiers (except for `\setfontsize`) work only with Unicode fonts loaded by \^`\fontfam`. \secc[fontfamfiles] How to create the font family file %------------------------------------------------------ \printdoctail f-heros.opm \printdoctail f-lmfonts.opm \secc How to register the font family in the Font Selection System %--------------------------------------------------------------- \printdoctail fams-ini.opm \endinput 2023-06-16 \fontfamsub improved. 2023-05-30 \catalognextfam introduced. 2023-04-22 \setwordspace: \fontdimens reset, bug fixed. 2023-03-09 \_famsrc, \fontfamsub introduced 2022-12-01 \faminfo saves f- to the format only when needed 2022-11-08 \protected: \fontdef, \famvardef, \fontfam 2022-02-22 Font Selection System reimplemented, \fontsel introduced 2021-09-24 \_unichars used in \initunifonts 2021-07-16 \initunifonts: optex_hook_into_luaotfload added. 2021-05-23 concept of \_fontfeatures macro re-implemented 2021-05-02 simpler \_resizefont, better concept of doc, moving parts from fonts-resize 2021-04-22 \_ffonum introduced 2021-04-19 \setwordspace: parameter format {/A/B/C} implemented. 2021-02-25 \_ttunifont introduced 2021-01-27 lua hack (print function) removed because luaotfload 3.17 removes bug. 2020-12-12 \_modlist added, doc improved 2020-04-18 \_tryloadfamslocal introduced \_fontdecl -> \_famdecl with different concept 2020-03-18 released