Our box drawing character range is too broad (was: \u25ef rendered too big)

[mrbeardad]

Windows Terminal version

1.18.3181.0

Windows build number

10.0.22621.0

Other Software

lazygit v0.40.2
nerdfont v3.1.1 SauceCodePro

Steps to reproduce

\u25ef -> ◯

Expected Behavior

render correctly when turn off atlas

Actual Behavior

[DHowett]

This is a two-part problem.

1. A font authoring issue. There is no glyph in "Sauce Code Pro" for U+25EF.
2. The engine cuts it off instead of letting it extend outside its boundary. @lhecker, Atlas Engine believes all glyphs in range U+2500 to U+25FF to be block elements, but in truth the box drawing and block elements blocks only extend from U+2500 to U+259F. The block after that is "geometric shapes".

Even if we fix 2, the circle will not look ideal since it is much bigger than a single monospaced character cell. If you want it to look right, choose a more complete font.

[j4james]

Font fallback configuration could possibly also help with scenarios like this (#2664).

[mrbeardad]

Another question, does atlas always cut glyph off rather than scale it?

[DHowett]

Font fallback configuration could possibly also help with scenarios like this (#2664).

Absolutely!

Another question, does atlas always cut glyph off rather than scale it?

No. For normal glyphs (see bug 2 in #16451 (comment)), Atlas always allows the glyph to extend out of bounds. It is incorrect to scale glyphs down, as we have seen with characters from non-en-US languages and italic or bold text.

[lhecker]

I'd like to leave this issue open to track the U+259F vs. U+25FF you mentioned, Dustin.

But that aside, I also don't personally wish to specifically address the ◯ glyph right now. Scaling glyphs down, as we've done with the old text renderer, has lead to all sorts of similarly subtle bugs over the years and I don't really want to reintroduce them. I'd rather implement customized font fallback in a future Terminal version.

[lhecker]

Oh right, this was fixed with #16729.