GitLab

* Describe how to exhaustively pre-generate all tiles

* clarify that `tileCoords` contains tile coordinates, not tiles

* Support for topojson in example

* Add topojson global

* start at supporting far away worlds

* test 3 world limit

* rename and lint

It's not strictly required, but it's useful metadata, and part of the recommended license template text (see http://choosealicense.com/licenses/isc/ and https://opensource.org/licenses/isc-license)

Save empty tiles at the bottom of the pyramid, per https://github.com/mapbox/geojson-vt-cpp/pull/47#discussion_r68474205 (#65)

ignore features with null geometry

As per the GeoJSON spec, "A feature object must have a member with
the name "geometry". The value of the geometry member is a geometry
object as defined above or a JSON null value." [1]

[1] http://geojson.org/geojson-spec.html#feature-objects

Previously when there was a null geometry there would be a JS error
in trying to access feature.geometry.type.

this is for consistency; it would be nicer to take buffer into account
but we can handle this later, not a big deal.

Turns out this is an extremely rare use case and the public method is
easy to misuse, so let’s move this code to external repo, just reusing
the files from the repo.