Hello there,
Following a discussion in
this thread, I thought it would make sense to create a new thread on the topic of non-linear interpolation.
The principle is explained very nicely (I think) by Underware
here.
I'm personally interested in this, because I'm trying to create an animated version of a typeface I'm working on. Of course one could simply animate it in animation software, but HOI in a variable font would be a much more elegant and flexible solution. Obviously this is just one example use for HOI, the possibilities are endless.
So, is there any chance we will see HOI become part of the variable fonts spec? Are there any work-arounds or alternatives to animation? And what would be the key arguments for making HOI a reality?
Lots of questions, I know. Just throwing it out there.
Cheers,
Jasper
Picture by Underware:
https://underware.nl/case-studies/hoi/
Comments
That said, I've not played directly with any HOI fonts, and don't know what environment dependencies might exist. This is why I consider the mechanisms used to be loopholes — which sounds nicer than 'hacks' —, because the behaviour is undefined in the spec, so platforms might interpret the data in different ways.
Just have a look at grammato.com.
There already exists an open version of the OpenType spec: the Open Font Format (ISO/IEC 14496-22:2019). I could imagine that if MS continues to stall on the OpenType spec per se, new-stuff momentum might shift to the Open Font Format.
Something between those two approaches would be best: an established but less bureaucratic and more flexible framework than ISO, and a more open and transparent process than the ad hoc working groups. For a while, I thought W3C might be a good place, because their draft it, build it, publish it approach to specification seems like a good model for a font format, but given the obvious synergies between text encoding and text display, and the significant crossover of individual expertise and engagement, I think Unicode would probably be the best place.
That being said, this thread (and much later the above issue) got me thinking about how there seems to be a lot of interest in HOI but not a lot of explanation of the actual nuts and bolts, which would help in understanding what can and cannot be done. Then I realized that I didn't really know either, so I wrote up an explainer to try and explain it to myself. At the moment this is a very terse explanation with a bit of math on bezier curves and assumes some prior knowledge of how 'fvar' and 'gvar' work. It could also really use some animations. It does work everything down to an actual example font which is fun to play with in Samsa. As terse an explanation as it is, hopefully it's helpful.
Understanding Non-Linear Interpolation in OpenType Variable Fonts
You can request a copy of the plugin at pkolchanov.ru/nla