makeotf: Within a ‘vkrn’ feature, value record format A should set YAdvance about afdko HOT 6 CLOSED

This is indeed a bug. The feature specification says explicitly Here the <metric> represents an X advance adjustment, except when used in the vkrn feature, in which case it represents a Y advance adjustment. For the moment, you can work around it by using the record value format B: < 0 0 0 -100>.

from afdko.

As Ken Lunde pointed out to me, the logic does work correctly for a kern pair. The bug exists only for a single glyph positioning adjustment. I will fix this, but out of curiosity, do you have a use case for a single glyph positioning statement in vkrn?

from afdko.

The 'vpal' GSUB feature is probably the better vehicle for such a metrics adjustment.

from afdko.

Should “vpal” (and other vertical features) trigger the vertical interpretation of ValueRecord format A? From the current spec, the answer seems “no” — should the spec could be adjusted?

from afdko.

Seems like a good idea to me.

from afdko.

Fixed, in makeotf and in feature file spec v 1.19

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