Mapbox-gl-js: Improve rendering of glyphs with thin strokes

[rasagy]

Steps to Trigger Behavior

Use a typeface with thin strokes (Calligraphic fonts like Gothic Ultra, Kingthings etc)

Expected Behavior

Expect the type to be rendered with more detail (especially the thin strokes)

Actual Behavior

Gothic Ultra:

Kingthings:

Slippy map

[kkaefer]

also see https://github.com/mapbox/mapbox-gl-native/issues/137

[lucaswoj]

@rasagy You can read a little bit more about the way we render glyphs here: https://www.mapbox.com/blog/text-signed-distance-fields

[mourner]

Currently no plans to pursue this (see also discussion in https://github.com/mapbox/mapbox-gl-native/issues/137)