Better line breaking

[ansis]

It should be possible to set a max label width and then line-wrap.

[kkaefer]

Note that we have to do this on the server when we calculate the shaping with pango. Pango accepts a maximum width and wraps according to writing direction.

[ansis]

If the server added an indication of where breaking is allowed, and the direction of the text, could we do the rest on the client?

[nickidlugash]

Just curious where we are on this.

POI labels are particularly troublesome without line-wrapping:

tracking for Outdoors style: https://github.com/mapbox/gl-ported-maps/issues/2

[mikemorris]

@springmeyer What do you think of @ansis' suggestion? I've seen how mapnik implements this, haven't ported over to fontserver yet though.

[springmeyer]

Yes, @ansis's suggestion sounds reasonable to me. Variable wrap-width is pretty critical as evidences with a quick scan of https://github.com/mapbox/mapbox-streets-style.tm2/blob/master/label.mss.

[mikemorris]

Opened mapbox/node-fontnik#28

[ansis]

we might be able to do this in the browser.

https://github.com/devongovett/linebreaker
http://www.unicode.org/Public/6.2.0/ucd/LineBreak.txt

The table could probably be compressed and/or simplified well enough for our needs. The algorithm itself is pretty simple

[mikemorris]

Implemented by @ansis in 9f25d1b

[mikemorris]

This will eventually need to break on more than just spaces, using the Unicode line breaking algorithm referenced by @ansis.

http://www.unicode.org/Public/7.0.0/ucd/LineBreak.txt
http://rishida.net/scripts/samples/wrapping.html

[mourner]

I think what we have after 53b81da is good enough for now.