[web app] Are there metrics labels available?
Looking at a font in Samsa, I see that one of the font metrics(?) plunges way down around wght=200, and I’m not sure why, or what that value might be:
https://github.com/Lorp/samsa/assets/45946693/12e83349-51f2-4def-b7cf-945d248b703d
Is there a way to see a label for that within the app?
Oh, I think I found it!
Looks like it might be stro (strikeout offset) within the mvar table.
I’ll dig a little further to see if I’ve set that with a silly mistake, somewhere.
The OT Spec relates stro to OS/2.yStrikeoutPosition:
| 'stro' | strikeout offset | OS/2.yStrikeoutPosition |
|---|
So, after looking into the font slightly further, I’m wondering if Samsa is being inaccurate here.
If I use the FontTools Instancer to instance the variable font at wght=200 vs wght=750 (opsz=72 in both), then inspect with TTX, the OS/2.yStrikeoutPosition is different but pretty similar:
-
<yStrikeoutPosition value="633"/>for wght=200 -
<yStrikeoutPosition value="615"/>for wght=750
Here’s a variable font that exhibits the issue (it has a limited/trial glyphset, so I can share it here, and folks are welcome to use it for testing purposes / inspecting internal font data:): AT-NameSansVariable.Trial.ttf.zip
Thanks for the report. I didn’t complete MVAR handling to my satisfaction, so I don’t think it’s reliable for now. I’ll take a look soon.