Replace one Glyph with Many

Hello folks. :slight_smile:
To outline my problem I am in the situation of alternating an existing font to get rid of some redundant tasks within the workflow that I feel could be done on the fly by correct use of OT features.
The font is used as an all caps headline font in german. Ä Ü are altered and Ö is supposed to be replaced by O E …

Right now Ä Ü are altered I am using components of O E within the Odieresis glyph—kind of a dirty hack—but it just works fine for this task.
Out of curiosity I am now interested if it is even possible to replace Odieresis with the glyphs of O and E. I read something about the GSUB lookup type 2 but I wasn’t able to find an explanation answering my question on how to actually do it.

I am more than happy if someone is going to answer my question and makes me a little bit smarter again. :smiley:
Cheers imik

Put this in a feature that makes sense for you, maybe titl:

sub Adiereis by A E;
sub Odieresis by O E;

And so on. It is more complicated if you need to limit it to certain contexts only.

Thank you for your quick reply. :slight_smile:
I tried it out quickly putting into the titl feature. It works fine but not in the actual layout programs of choice: Adobe …
I can turn the feature on and of in other programs like the font managing program, textEdit etc.
A while back I had a similar problem on another project that features where not working in Adobe InDesign and Illustrator but I didn’t had the time to dig into this problem. Do you have an idea what could cause this problem?

It works in Adobe InDesign. AI does not support titling case, I think.

For one to many substitutions to work in Indesign, you need to activate the ‘World Ready composer’.