Using variable fonts

[gaborpapp]

I see that variable fonts are supported with the -varfont parameter, but I cannot figure out how to specify which typeface to use from the font file. Any help would be appreciated.

[gaborpapp]

I tried setting something like this: -varfont font.otf?wght=900&wdth=200, I had to escape ? and &, because I'm not on Windows.
Whatever I did I got the same default result. So I ended up converting the font instance to a static font with fonttools.

[Chlumsky]

Can you provide the font so I can test it?

[gaborpapp]

Sure. Is it ok if I send a link by email?

[Chlumsky]

No problem.

[Chlumsky]

The variable axes of this font are named

• Width (50 to 200),
• Weight (200 to 900),
• and ital (0 to 1).

So you can use for example -varfont "Obviously.otf?Width=100&Weight=500&ital=0.5"

[gaborpapp]

Thanks a lot! This indeed works.
May I ask how you figured out the axes? Both https://wakamaifondue.com/ and ttx lists wdht, wght and ital.

<!-- Width -->
<Axis>
  <AxisTag>wdth</AxisTag>
  <Flags>0x0</Flags>
  <MinValue>50.0</MinValue>
  <DefaultValue>50.0</DefaultValue>
  <MaxValue>200.0</MaxValue>
  <AxisNameID>263</AxisNameID>
</Axis>

<!-- Weight -->
<Axis>
  <AxisTag>wght</AxisTag>
  <Flags>0x0</Flags>
  <MinValue>200.0</MinValue>
  <DefaultValue>200.0</DefaultValue>
  <MaxValue>900.0</MaxValue>
  <AxisNameID>264</AxisNameID>
</Axis>

<!-- Italic -->
<Axis>
  <AxisTag>ital</AxisTag>
  <Flags>0x0</Flags>
  <MinValue>0.0</MinValue>
  <DefaultValue>0.0</DefaultValue>
  <MaxValue>1.0</MaxValue>
  <AxisNameID>265</AxisNameID>
</Axis>

[Chlumsky]

I got it directly from FreeType's FT_Get_MM_Var listed as FT_Var_Axis::name. It's though possible that this is not the best source of the axis names for the library so if anyone has a better suggestion, let me know.

[gaborpapp]

The problem is that they don't seem to match with other sources, but since we need to use the axis names for Freetype anyway, it would be a nice feature to add a command line parameter to list axis names.