unicode-range glyph PBFs

[yhahn]

@mikemorris

• Be able to package glyph PBFs independently of vector tiles, basically if someone asks for character range <from>-<to>, hand them back the PBF for those characters. Yes, we know this won't handle shaping.
• Hook this up to some HTTP endpoint.
• See how having llmr retrieve glyph PBFs independently of vector tiles behaves/performs.
• This is either a massive fail or promising and we can look into how to approach shaping for character sets that need it.

Background/goal/interest: being able to have a GL spec that is not tied to a running server. e.g. once glyph PBFs are generated for a given fontset they could be distributed/hosted on S3 or any webserver or locally for demos and when explaining how the whole system works to other devs.

[yhahn]

Also, yes, we've all assumed this would perform horribly and blow up in our face. I want to see it for myself before dismissing it : )

[springmeyer]

This will be huge.

[mikemorris]

Tracking in https://github.com/mapbox/fontserver/tree/glyphrange

[yhahn]

Deployed @mikemorris's work today so you should be able to get to these range glyph PBFs now.

cc @ansis

[mikemorris]

So this looks very promising outside of Asia, but, um, 11 megabyte glyph range protobufs seem like a problem.

/cc @yhahn

[yhahn]

Per voice, thinking we should just have the server start responding 400 for now after cyrillic or armenian (https://github.com/mapbox/llmr/compare/glyphrange#diff-98670d9a9d7579d7f13daf74887fd97bR156) and slowly start expanding upwards as we figure out how we'll shape Arabic and handle challenges like the CJK block.

[mikemorris]

This is now in master, next steps in #36