Hello, I was testing matching of fonts with a :postscriptname pattern with partial name matching, for example "Noto", "Liberation", "Deja". I know that FontConfig doesn't support matching with wildcards and I know these loosely qualified patterns are cringe. Still API FcFontMatch and/or fc-match seem to do a bare minimum to handle them, but fail with a less trivial pattern, casting some doubts they are really respecting the contract of "using the normal fontconfig matching rules to find the best font available" (as per the documentation). First I make the questions, then I elaborate them: 1) Why a :postscriptname pattern partially matching name seems it can't be used together a :style pattern? 2) Why match on a :postscriptname doesn't perform more pattern normalizations? For examples it trims spaces, which is good, but it doesn't (for example) convert commas ',' to hyphen '-' (which it would in general match more fonts); 3) Why partial match on :family produces even worse results than on :postscriptname? Elaborating the questions, at first I actually tried doing some partial matches on family name, and the results were quite bad: $ fc-match ":family=Liberation" postscriptname style family Noto Sans:style=Regular:postscriptname=NotoSans-Regular ... (notice it returned a Noto font instead of any available Liberation font). Then I tried with matching :postscriptname and these matches seem to to be promising: $ fc-match ":postscriptname=Liberation" postscriptname style family Liberation Mono:style=Regular:postscriptname=LiberationMono $ fc-match ":postscriptname=Noto" postscriptname style family Noto Mono:style=Regular:postscriptname=NotoMono $ fc-match ":postscriptname=Deja" postscriptname style family DejaVu Sans:style=Book:postscriptname=DejaVuSans At this pointed I really want to enforce a scalable font, and not a monospaced one. This works: $ fc-match ":postscriptname=Liberation:spacing=0" postscriptname style family Liberation Sans:style=Regular:postscriptname=LiberationSans But if I also want an italic font (which is definitely available) then this fails: fc-match ":postscriptname=Liberation:spacing=0:style=Italic" postscriptname style family Liberation Sans:style=Regular:postscriptname=LiberationSans The behavior is reproducible using the linked testbed which has a small font database[1] (with small differences, as it seems to prefer "Bold" fonts to "Regular" ones), using the latest FontConfig git revision. As one more discussion point, I noticed that some pattern normalization is performed in :postscriptname, as for example trimming spaces. For example the following works, which is great: fc-match ":postscriptname=Liberation Sans-Bold" postscriptname family style Liberation Sans:style=Bold:postscriptname=LiberationSans-Bold But that's seem to be the only normalization performed, and the following match will fail: fc-match ":postscriptname=LiberationSans,Bold" postscriptname family style Liberation Sans:style=Regular:postscriptname=LiberationSans Please consider that using the comma as in "LiberationSans,Bold" is quite a common convention as suggested in the PdfReference for a long time (before ISO standardization) to compose a postscript name for the font (read 5.5.2 TrueType Fonts in PdfReference 1.7[2], suggestion removed starting with ISO 32000-1:2008). Thank you for your attention. Cheers, Francesco [1] https://github.com/user-attachments/files/17990992/testpsmatch.zip [2] https://opensource.adobe.com/dc-acrobat-sdk-docs/pdfstandards/pdfreference1.7old.pdf
