Coordination

[springmeyer]

The goal of this library is to start sharing core types for geometries.

The primary motivation is to enable ABI compatible, zero-copy operations between modular C++ libraries when they are combined into the same program.

A secondary motivation is general code sharing across C++ codebases implementing support for GeoJSON-like/OGC style geometries. The focus will be on Mapbox maintained code, but this library should be easily pluggable anywhere.

Running list of the primary downstream consumers this library is prioritizing and integration needs (will be editing in place):

Downstream

• geojson-vt-cpp: https://github.com/mapbox/geojson-vt-cpp
  • Relevant files:
    • https://github.com/mapbox/geojson-vt-cpp/blob/f9edd5c7b7b8717f1ca8139712210517221fb982/include/mapbox/geojsonvt/types.hpp#L14-L70
  • Team to coordinate with: @mourner
• mapbox-gl-native: https://github.com/mapbox/mapbox-gl-native
  • Relevant files:
    • https://github.com/mapbox/mapbox-gl-native/blob/e7ac0f6d4c39fed294effaed3ccd1d423fb4d913/src/mbgl/renderer/fill_bucket.hpp#L59
    • https://github.com/mapbox/mapbox-gl-native/blob/2656b5c733a7c7a18f81c80518e4bfef75b03582/include/mbgl/util/vec.hpp
    • https://github.com/mapbox/mapbox-gl-native/blob/41f63db98bb0f1bd960b3555c20d8f09c212dbc5/include/mbgl/util/geo.hpp#L16-L168
  • Team to coordinate with: @jfirebaugh
• vector-tile: https://github.com/mapbox/vector-tile
  • Team to coordinate with: @flippmoke @ericfischer
• mapnik: https://github.com/mapnik/mapnik
  • Relevant files:
    • https://github.com/mapnik/mapnik/blob/f5d6af4bb86240b7e41b60e3d910aae5bf40af88/include/mapnik/geometry.hpp#L36-L58
  • Team to coordinate with: @artemp
• OSRM: https://github.com/Project-OSRM/osrm-backend
  • Team to coordinate with: @danpat
  • Relevant files: https://github.com/Project-OSRM/osrm-backend/blob/master/src/engine/plugins/tile.cpp

[springmeyer]

Progress so far:

• tippecanoe: Use geometry.hpp tippecanoe#244
• mapbox-gl-native: [core] Use geometry.hpp's point type mapbox-gl-native#4951 and [core] Use geometry.hpp feature type mapbox-gl-native#4921
• geojson-vt-cpp: [WIP] Use mapbox::geometry geojson-vt-cpp#39

[mourner]

Also: https://github.com/mapbox/geojson-cpp. It will be used in gl-native, and indirectly geojson-vt-cpp and supercluster.hpp.

[jfirebaugh]

Biggest remaining integration task in mapbox-gl-native is to replace these types with geometry.hpp's geometry type.

@mourner put it perfectly: "the choice is either to get rid of this first and then integrate new geojson-vt & supercluster effortlessly, or write tons of conversion code"

[springmeyer]

Back here to update more success in code sharing and adoption of geometry.hpp:

• Mapnik: Geometry.hpp mapnik/mapnik#3646
• Supercluster.hpp: https://github.com/mapbox/supercluster.hpp
• mapbox/vector-tile: https://github.com/mapbox/vector-tile

Next step I'm seeing here before closing is to (I will do this):

• Update the readme with a more detailed description of what this library is about. I will include a description that algorithms are out of scope for geometry.hpp core but nevertheless a critical usecase and are being developed at https://github.com/mapbox/spatial-algorithms
• Add links to downstream users