Layered Colour Font – Metrics Best Practice


I’ve been making some edits to a layered color font I made a couple of years ago in an older version of Glyphs.

I note that I had included specific metrics for both Width and Weight for each master (matching in each master of course).
I also see that I’ve also included a pair of Stem Values in both Vertical and Horizontal sections (also matching in each master).

My questions are:
Should the Width and Weight values be generic since they are unlikely to be accurate for all masters? (The tutorial image shows them at 100 / 100)

Should stem weights also be generic or not added at all, as they also can’t be accurate across all masters? (There’s no mention of this in the tutorial or handbook)

Might there be any connection with these metrics and this issue: Myfonts font rendering is corrupted

Thanks loads


The interpolation values are arbitrary. They are just for calculating, so they do need to be different somehow, otherwise you cannot differentiate. Pick numbers that make sense to you. Usually that would be the size of the stem. But whatever helps you keep the oversight, is OK.


Are you speaking about the Axis coordinates or the Stems.

In a layer font you usually don’t need hinting. So you don’t need stems either.


Thanks Both.

My question was for each type of metric.
If the weight/width are arbitrary I can add any number that makes sense.
With the stems, since there is no interpolation or hinting, is it be to leave them blank?



Stems are only needed if you have hinting. So you can omit them.


OK. Thanks!