Setting fonts repeatedly with different covers is not effective #6566
Description
Description
In the following example, the font Libertinus Serif support all characters in the text 123.
If I set text.font to ((name: font, covers: regex("1")), font), then the second item in the list (font) is not effective, leading to 1⬜⬜ rather than 123.
#let font = "Libertinus Serif"
#text(font: font)[123]
#text(font: (
(name: font, covers: regex("1")),
font,
))[123]
Full code
#set page(height: auto, width: auto, margin: 1em)
#set text(fallback: false)
#let font = "Libertinus Serif"
#text(font: font)[123]
#text(font: (
(name: font, covers: regex("1")),
font,
))[123]Is this behaviour expected?
Use case
The above is a minimal but meaningless example, and here's a real example.
I am using Twitter Color Emoji font, but the official version didn't update after Unicode 14. Therefore, I use Noto Color Emoji as a fallback.
However, I want to use both 🔗 link (Unicode 6.0) and ⛓💥 broken chain (⛓+zwj+💥, Unicode 15.1). These two emojis are used in pairs, but only the former is included in Twemoji. As a result, I want both of them fallback to Noto Color Emoji.
To sum up,
- For 🔗 and ⛓💥, use Noto Color Emoji.
- For other emojis, use Twitter Color Emoji if possible.
- For other emojis, use Noto Color Emoji.
That is,
#set text(font: (
(name: "Noto Color Emoji", covers: regex("[🔗⛓💥]")),
"Twitter Color Emoji",
"Noto Color Emoji",
))
Full code
#set page(height: auto, width: auto, margin: 1em)
#import emoji: chain, fingerprint, key
#let broken-chain = emoji.chains + sym.zwj + emoji.explosion
// https://github.com/googlefonts/noto-emoji/blob/b3e3051a088047d19fd4d49b1c3ac42fb8c3aaf8/fonts/NotoColorEmoji.ttf
// Note that this version is newer than that in typst.app.
#let font-n = "Noto Color Emoji"
// TwitterColorEmoji-SVGinOT.ttf in https://github.com/13rac1/twemoji-color-font/releases/download/v14.0.2/TwitterColorEmoji-SVGinOT-14.0.2.zip
#let font-t = "Twitter Color Emoji"
#set text(font: ("Libertinus Serif", font-n), fallback: false)
#table(
stroke: none,
align: start + horizon,
columns: 3,
table.hline(),
table.header()[*Font*][*Current*][*Explanation*],
table.hline(stroke: 0.5pt),
font-n, text(font: font-n)[#chain#broken-chain#fingerprint#key], [✅✅✅✅],
font-t, text(font: font-t)[#chain#broken-chain#fingerprint#key], [✅💔❌✅],
[Noto (#chain#broken-chain), Twitter, Noto],
text(font: (
(name: font-n, covers: regex("[" + chain + broken-chain + "]")),
font-t,
font-n,
))[#chain#broken-chain#fingerprint#key],
[✅✅⬜✅],
[Expected of the above],
text(font: (font-t, font-n), {
text(font: font-n)[#chain#broken-chain]
[#fingerprint#key]
}),
[✅✅✅✅],
table.hline(),
)
#set text(0.7em)
- ✅ = OK
- 💔 = This is a zwj-joined emoji, but splitted
- ❌ = Missing / fallback
- ⬜ = Tofu(Yes, there are many workarounds for this specific demand: #let broken-chain = text(font: …, …), show "⛓💥": …, etc.)
A related post
What is the designed behaviour of font covers in math equations? - Questions - Typst Forum
Reproduction URL
No response
Operating system
Windows
Typst version
- I am using the latest version of Typst