POI icons are blurry

[kkaefer]

With the new changes, the POI icons are blurry. Also, they're way too small on retina screens.

[ansis]

#102 would be one approach to fixing this for unscaled/unrotated icons.

As you mentioned, using sdf for things like oneway arrows would be great. This probably won't help with maki blurriness though.

[ansis]

Retina icon regression fixed in 874b8ac

[ansis]

4d496b4 fixes most blurriness by using linear filtering only when the icon is rotated (line markers) or when the map is rotating (to prevent jiggling). The switch between linear/nearest is slightly noticeable, but this isn't something that can be avoided.

Splitting support for sdf incons into #161. sdf will be useful, but won't help reduce blurriness for complex icons that are as small as what we're currently using (12px).

[kkaefer]

Can we turn on linear filtering when the user is zooming, and back off if zooming stipped? Otherwise you'll still see a slight jiggle effect when zooming with the trackpad.