Variable font export problem (calculated instances)

Hello everyone! I am currently working on a complex variable font design with 8 axes for my graduation project. It is not a typical font as it only uses punctuations, accents and symbols and the different masters aren’t typically matching (i.e. bold light etc), they instead try to show emotions.

I have been fixing my drawings so the calculated instances look correct, with very little kinks etc. Within the glyphs app and using the variable preview tool, instances look good and they are all compatible (top).
But once I export my font in variable format, the same instance looks like this (bottom):

When I export my font in classic ttf or otf format with all instances but no variable features it looks correct, just like in Glyphs.

If anyone of you has an idea why the export won’t work properly despite having no error message I would appreciate the help, thank you :slight_smile:

Can you show how you drew the paths, and what your master setup is? What axis coordinates did you use?

All the paths are compatible, the transistion is sometimes rough because of the design but I have corrected most of it in the file and this is what Glyphs shows me.

I have 8 axis, each goes from the same master at 0 to 1 corresponding master for each at 200, so the two extremes are drawn. And then I have calculated instances mixing 2 axis (100-100 on the corresponding axis) which are the ones that don’t export well in variable but export correctly in classic individual files.

You probably need 2^8 = 256 masters for a variable font to work reliably, but some might be skipped depending on the design and where the Origin is (which seems hard to understand). Static instances are more forgiving.

I wonder if one day Glyphs will take care of the missing masters on export. Unless I’m behind the updates on all this :slight_smile:

You most certainly don’t need all those masters. And just filling up the full space is not a good idea. As interpolating something in a corner will blow up either when doing it in Glyphs or when letting to variable font do it.

Can you show some screenshots that show what you get from the variable font and what you would expect?

Fair enough, I thought mostly about finishing the grid with intermediate masters/layers which is where we usually get differences between static and variable