Choosing the right font format to package
Navigating the multi font format hell
In this page:
- OTF is used as an abbreviation for the OpenType CFF format,
- TTF is used as an abbreviation for the OpenType TT format.
The following decision tree is used to choose the font format to package in Fedora:
- If upstream works with one preferred OpenType format (TTF or OTF), use this format.
- If a font is available in both TTF and OTF versions, package the most recent (timestamp) and complete (size) version.
- If both formats are generated from the same source upstream, package the OTF version.
- Most font editors work with cubic splines natively, and we don't ignore CFF hinting the way we do TT hinting (different legal context), so the OTF version may be slightly better for us.
- For already packaged fonts, continue to package the TTF format till OpenOffice.org is fixed.
- The rationale is to avoid upsetting users that already created documents using the TTF version.
- After OpenOffice.org is fixed apply the same policy as for new packages.
- As an exception, a package maintainer is authorized to use his best judgement and package both versions in a single rpm, if a user manages to convince him it's not a terribly bad idea.
- Never do it by default.
- That will double the package size so livecd and bandwidth-constrained users won't be happy about it.
- Also we have little control on the version fontconfig will serve to applications.
- But at least the packaging will be simple.
- Since it seems several projects use different font names for the OTF and TTF variants, systematically package a fontconfig ruleset that maps the font name we do not package to the one we do.
And lastly :
- Do not package new Type1 fonts. If someone cares about a Type1 font, he should get it converted to OpenType CFF before we consider packaging it.