TODO - Map quality

Geometry

try fixed pt again, for determinism purposes mostly
- successful: Lines of ~0 length gone
- but due to bad polyline shifting, some things would loudly break if we squished pts down always
underlying problems
- bad polyline shifting remains
  - from the remaining cases, looks like we need to totally remove some tight points and retry
  - make polygons use the corrections too?
generalized_trim_back
- breaks down when we have jagged lane endings due to polyline shift angle correction
- sometimes a lane polyline hits the perpendicular of a trimmed road! where was this happening?
handle small roads again somehow?
- VERY overeager... ate half of the map
  - can we capture snapshots of incremental changes?
    - save initial map at every step, be able to load raw + initial with a focus point
  - try merging the shortest roads first
- deal with loop roads
- manually draw a picture of the weird intersection to see what would look reasonable. i think we need original road bands from deleted stuff to make decent polygons.
- model U-turns
degenerate-2's should only have one crosswalk
- then make them thinner
ped paths through sidewalk corners are totally broken
- calculate the better paths first, then make the corner geometry from that?
car turns often clip sidewalk corners now
figure out what to do about yellow center lines
- intersections on one-ways look weird
- yellow and white lines intersect cars and turn icons and such
- who should own drawing them?

if building front path intersects another building, then scrap that building.
- or wait, just require bldgs to be even closer to sidewalk first.
- need to do polygon vs polygon check!
- will need to speed it up with quadtree containing entire buildings. make sure these are easy to use.
can we make OSM buildings with holes?
- experiment with https://docs.rs/clipping/0.1.1/clipping/gh/struct.CPolygon.html and https://github.com/21re/rust-geo-booleanop