Cannot enable the "ss07" feature in FiraCode font

[MarcosBaungartner]

Greetings,
I'm trying to enable the ss07 feature in FiraCode font, but it doesn't working.

Command:

pyftfeatfreeze -n -v -f "ss07" FiraCode-Regular.ttf FiraCode-Regular-ss07.ttf

Output:

INFO: [RemapByOTL] Running with options: Namespace(features='ss07', info=False, inpath='FiraCode-Regular.ttf', lang=None, names=True, outpath='FiraCode-Regular-ss07.ttf', rename=False, replacenames='', report=False, script='latn', usesuffix='', verbose=True, zapnames=False)
INFO: [openFont] Opened font: FiraCode-Regular.ttf
INFO: [filterFeatureIndex] FeatureIndex: [3, 19, 35, 51, 67, 93, 109, 125, 141, 157, 173, 189, 205, 221, 237, 253, 269, 285, 301, 317, 333, 349]
INFO: [filterLookupList] Features to apply: ['ss07']
INFO: [filterLookupList] Lookups: [138, 139]

INFO: [saveFont] Saved font: FiraCode-Regular-ss07.ttf
INFO: Finished processing.

This command with these feature works fine:

pyftfeatfreeze -n -v -f "ss01,ss03,ss05" FiraCode-Regular.ttf FiraCode-Regular-ss01-03-05.ttf

[Axel-Shark]

I'm not having any luck either. If I pass "ss02,ss03" I get an error for the 3 changes. If I do "ss02, ss03", I only get an error on <= and >= (so & should have gone through), but the change isn't registered when I re-select Fira Code regular. Doesn't seem to be baked.

[MarcosBaungartner]

I'm not having any luck either. If I pass "ss02,ss03" I get an error for the 3 changes. If I do "ss02, ss03", I only get an error on <= and >= (so & should have gone through), but the change isn't registered when I re-select Fira Code regular. Doesn't seem to be baked.

If i put a space like "ss03, ss05" it doesn't work.
You don't need the quotes, try this:
pyftfeatfreeze -n -v -f ss02,ss03

[Axel-Shark]

From this command I get the following warnings:
pyftfeatfreeze -n -v -f ss02,ss03 FiraCode-Regular.ttf FiraCode-Regular-ss02-03.ttf

INFO: [applySubstitutions] Remap: 'ampersand' -> 'ampersand.ss03'
WARNING: [applySubstitutions] Cannot remap 'ampersand_ampersand.liga' -> 'ampersand.ss03' because neither has a Unicode value assigned in any of the cmap tables.
WARNING: [applySubstitutions] Cannot remap 'greater_equal.liga' -> 'greater_equal.ss02' because neither has a Unicode value assigned in any of the cmap tables.
WARNING: [applySubstitutions] Cannot remap 'less_equal.liga' -> 'less_equal.ss02' because neither has a Unicode value assigned in any of the cmap tables.

[twardoch]

Yes, that is as designed.

[Axel-Shark]

Ah ok. Thanks. First time trying to use this or bake in ligature changes. So disregard warnings? Still not seeing the ss02 and ss03 changes in the font on reload.

[twardoch]

It should remap 1:1 glyphs where the source has a Unicode. Ligatures won’t work.

[MarcosBaungartner]

But if i enable these settings in Visual Studio Code, they all work swiftly:

In settings.json:
"editor.fontLigatures": "'true', 'ss07'",

[twardoch]

You can use ligatures when they’re OT features but the feature freezer cannot remap ligatures to default glyphs because they don’t correspond to a single Unicode character

[twardoch]

This tool moves the Unicode codepoints for a glyph that represents a single character — from the default glyph that has a Unicode to an alternate glyph (which is normally accessible via a feature). This tool only remaps 1:1 substitutions, while ligatures are n:1.

The tool also won’t work on “stacked features” e.g. for variants of ligatures, because the source glyph must have a Unicode.

[MarcosBaungartner]

Yes, i used "enable" as a matter of speaking.
I understand that it only remaps the Unicode, so the ss07 doesn't have a Unicode because it is a ligature, so the tool cannot remap that.
Thanks for clarify that.

[twardoch]

Yes, it further won’t work if a glyph is only accessible only through a combination of multiple features, which is not a systemic limitation, just of the implementation.

[arrowtype]

I’m uncertain whether I’m having the same issue or experiencing something different in my Recursive project.

arrowtype/recursive-code-config#4 (comment)

In Instanced statics, almost all stylistic sets will freeze in, except for a simplified i – even though its naming & substitution rules are almost exactly like other glyphs that are working. @twardoch do you think this is likely to be the same, or something different? (Thanks for such an amazing tool, by the way!)

[MuTsunTsai]

@mrbaungartner I made a new app that can handle your needs. Please check it out: https://mutsuntsai.github.io/fontfreeze/

[MarcosBaungartner]

@mrbaungartner I made a new app that can handle your needs. Please check it out: https://mutsuntsai.github.io/fontfreeze/

@MuTsunTsai Very nice tool, but it is throwing an error when I try to generate the FiraCode with ss01-03-05-08 features.

[MuTsunTsai]

@mrbaungartner Try start with FiraCode-VF.ttf (in the variable_ttf folder in the zip file); I have no problem generating ss01-03-05-08 with it. Please report further issue directly in the FontFreeze repo.

[MarcosBaungartner]

@MuTsunTsai It works with the variable_ttf, but it is lighter than the FiraCode-Regular.ttf (I get an error if I generate with a Weight of 450)

[MuTsunTsai]

@MarcosBaungartner Did you use the latest version of FiraCode (6.002)? I have no problem generating ss01-03-05-08 with weight 450 using FiraCode-VF.ttf. And please, do report further issue directly in the FontFreeze repo, as I won't be routinely checking replies here, and any further discussion would be off-topic here.