[blueblob]

With the ability to add parameters to fonts, I wonder how long it will be until we have Turing Complete fonts.

[CharlesW]

https://litherum.blogspot.com/2019/03/addition-font.html

"So this is pretty cool, but it turns out that the contextual substitution lookup type is really powerful. This is because the table that it references can be itself, which means it can be recursive."

[…]

"So thats a pretty powerful virtual machine. I think the above is sufficient to prove Turing complete-ness."

[raphlinus]

Behdad had this result earlier: https://twitter.com/behdadesfahbod/status/958065026262183936

[Diris]

Font hinting is already turing complete[0]. (I learned about the in this[1] iceberg meme)

[0] https://en.wikipedia.org/wiki/TrueType#Hinting_language

[1] https://suricrasia.online/iceberg/

[gorkish]

Postscript fonts? Fully programmable font glyphs in the 80's. Little used, but very fun. I recall a typewriter font that would vary the glyphs position, weight and edges a bit to simulate coming from a manual typewriter.

One could, if so inclined, build a complete COLRv1 font parser in PostScript.

[aaaaaaaaaaab]

TrueType already has a Turing-complete bytecode.