Hello, I use fallbacks to substitute "Arabic" digits in math to Indic ones. The mechanism doesn't work in the newest context. I tried it with mkxl version in 2025.02.04 17:52 in a clean install. The email is a bit long, but please bear with me, so I can learn a few other things along the way. Compiling type-imp-mathdigits.mkiv (provided in the distribution) does not change the digits to Indic form. This is the part after the typescript definition: \usetypescript [mathdigits] [xits-dejavu] [extendedarabicindic]
\setupbodyfont[dejavu] \starttext $3+2=5 \quad \bf 3+2=5$ \stoptext
The logs contain the following, which shows dejavusansmono is not loaded. mkiv lua stats > loaded fonts: 3 files: texgyredejavu-math.otf,
dejavuserif-bold.ttf, dejavuserif.ttf
IIUC one issue is that setupbodyfont kind of undoes the usetypescript command because dejavu typescripts already define MathRoman. Could you also explain the difference between setupbodyfont and switchtobodyfont? Do I need the latter? If I use the following instead, the Arabic digits do turn into Indic ones. \usetypescript [mathdigits] [xits-dejavu] [extendedarabicindic]
\setupbodyfont[dejavu] \definefontsynonym[MathRoman][MathRomanBold][fallbacks=mathdigits] \switchtobodyfont[sans]
With some caveats: 1) This still ignores the MathRoman definition in the above typescript (if I change the above to use euler, e.g., I see no change). 2) This only changes MathRoman and not MathRomanBold. So if I have something like {\bf $2+3$}, then the fallback does not kick in. 3) I can't use \definefontsynonym[MathRoman][MathRoman][fallbacks=mathdigits] because it creates a loop. Is there a way to "deep copy" font definitions (rather than the "copy by reference") we have here? That way, I could run the fallback for both MathRoman and MathRomanBold. Speaking of which, what's the difference between \definefont and \definefontsynonym? What happens when either of these appear within a typescript definition? Is the only difference, that within typescripts we have a separate namespace to which the Sans, Serif, MathRoman, etc. are attached? Can I access the MathRoman defined within typescript MyTypescript as "MyTypescriptMathRoman" or something like that? What about if I define BaseMath (a non-standard name, other than Sans, SansBold, MathRoman, etc.)? Are these also attached to that namespace? What is typescriptcollection BTW? Is it only cosmetic? Or can we pull in all definitions from a collection? Does it have to be the same as the file name? What's the difference between MathRoman and MathRomanBold? I thought when we would automatically get the Bold, Italic, BoldItalic variants when we define something like Sans. Or do we need to pull in some setups for that? For math, it seems that MathRoman has all the bold glyphs inside (at the digitsbold offset). Does it also have the bold version of other symbols? Then, what's the use of MathRomanBold? In the math typescripts, I see the feature "math\mathsizesuffix"? Is it for normal, script, scriptscript size? Who sets this macro? Are the math typescripts loaded multiple times with different \mathsizesuffix values? At what time? Back to the original question, if I switch usetypescript and setupbodyfont (see below), I see the math font changes taking effect (e.g., by picking up euler-math.otf instead of xits-math.otf). However, the fallback still doesn't work. \setupbodyfont[dejavu]
\usetypescript [mathdigits] [xits-dejavu] [extendedarabicindic] %\definefontsynonym[MathRoman][MathRomanBold][fallbacks=mathdigits] \switchtobodyfont[sans,20pt]
I need to uncomment the third line above to get the fallbacks to work. I feel that the digitsnormal in MathRomanBold (used in the fallback) is slightly bolder than the normal one, but my eyes may be failing me :) Now it gets more mysterious. See this code snippet: % no change from mathdigits file
\starttypescript [mathdigits] [dejavu] [arabicindic,extendedarabicindic] \resetfontfallback [mathdigits] \definefontfallback [mathdigits] [dejavusansmono] [digits\typescriptthree] [check=yes,force=yes,offset=digitsnormal] \definefontfallback [mathdigits] [dejavusansmonobold] [digits\typescriptthree] [check=yes,force=yes,offset=digitsbold] \stoptypescript
\starttypescript [mathdigits] [xits-dejavu]
[arabicindic,extendedarabicindic] \usetypescript [mathdigits] [dejavu] [\typescriptthree] \definefontsynonym[MathRoman] [file:xits-math.otf][features=math\mathsizesuffix,goodies=xits-math,fallbacks=mathdigits] % copied from comments of the same file \definefontsynonym[MathRomanDigitsXitsDejavu] [file:xits-math.otf][features=math\mathsizesuffix,goodies=xits-math,fallbacks=mathdigits] \stoptypescript
\setupbodyfont[dejavu]
\usetypescript [mathdigits] [xits-dejavu] [extendedarabicindic] % copied essentially from comments of the same file \definefontsynonym [MathRoman] [MathRomanDigitsXitsDejavu] \switchtobodyfont[sans,20pt]
\starttext
$3+2=5 \quad \bf 3+2=5$ math with fallback\\ {\bf$3+2=5 \quad \bf 3+2=5$ bold math}\\ {۳ + ۲ = ۵ \bf ۳ + ۲ = ۵ text Indic digits}\\ {3 + 2 = 5 \bf 3 + 2 = 5 text Arabic diigts}\\ %$$\sum_{i=1}^{8} x^2 = \pi\alpha + e^{-\beta}$$ \stoptext
If the last line is uncommented, I ran into the following error. Sorry, but I can't typeset math unless various parameters have been set. This is normally done by loading special math fonts into the math family slots. Your font set is lacking at least the parameter mentioned earlier. When it's commented, the fallbacks still don't happen, even if I rewrite the last definition as \definefontsynonym [MathRoman] [MathRomanDigitsXitsDejavu][fallbacks=mathdigits]. In some other tests (not with math), I noticed that in fallback definition, I also need to set the target key to be the same as the second parameter of the definition; something like: \definefontfallback [mathdigits] [dejavusansmono] [digitsarabicindic]
[check=yes,force=yes,offset=digitsnormal,target=digitsarabicindic]
But I don't have a MWE for it right now. Thanks a lot for your help, Mohammad