Random cool stuff I've been hacking on (mostly spatial indices)

Random cool stuff I've been hacking on (mostly spatial indices)

JSGeo 2017, August 15th

6d07e6d95a43357254698ce9723350e6?s=128

Vladimir Agafonkin

August 15, 2017
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  1. hello, friends!

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  3. random cool stuff I’ve been hacking on JSGeo, August 15th

    2017 Vlad (mostly spatial indices)
  4. github.com/mourner/rbush

  5. box queries

  6. finding nearest neighbors

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  11. • rendering and querying shapes in OpenLayers • processing shapes

    in MapShaper • placing labels and handling annotations in iD OpenStreetMap editor • interactive plotting in Bokeh real time apps
  12. • deriving road speed profiles and live traffic from telemetry

    data • deriving lane geometry, turn restrictions, one-way roads, sidewalks from telemetry data • detecting and fixing issues in OSM data • comparing road networks (e.g. OSM vs TIGER) map matching / processing
  13. map matching / processing • matching Wikidata against OSM for

    geocoding • TurfJS modules like line-intersect, line-split, line- overlap, dissolve, mask, collect • matching features against polygons (e.g. administrative classification) • concaveman: generating an outline of a point set
  14. github.com/mapbox/tile-reduce

  15. osmlab.github.io/osm-qa-tiles

  16. tile-reduce

  17. which polygon?

  18. github.com/mapbox/which-polygon

  19. github.com/mapbox/linematch

  20. buffer, union, difference: slow

  21. github.com/mapbox/linematch freaking fast

  22. github.com/mapbox/lineclip freaking fast

  23. github.com/mourner/rbush-knn

  24. distance from a point to a bounding box

  25. distance from a segment to a bounding box

  26. github.com/mapbox/concaveman

  27. github.com/mapbox/concaveman

  28. github.com/mourner/kdbush

  29. github.com/mourner/kdbush •supports points only (not boxes) •can’t add/remove points dynamically

    •indexing is 5–8 times faster
  30. github.com/mapbox/supercluster

  31. github.com/mapbox/supercluster

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  33. geodesic nearest neighbors?

  34. distance from a point to a bounding box on a

    sphere?!
  35. bbox on a sphere

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  37. convert to 3D coords?

  38. convert to 3D coords? •can’t use the same index for

    bounding box queries •imprecise for bigger distances •indexing and querying can be slow
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  42. when you found a use for differential math for the

    first time in a 13-year career
  43. github.com/mourner/geokdbush

  44. measuring distances fast

  45. measuring distances fast

  46. euclidean geometry with lat/lon

  47. euclidean geometry with lat/lon

  48. github.com/mapbox/cheap-ruler •distance •bearing •destination •lineDistance •area •along •pointOnLine •lineSlice •lineSliceAlong

    •bufferPoint •bufferBBox •insideBBox freaking fast!
  49. github.com/mapbox/earcut

  50. github.com/mapbox/delaunator

  51. github.com/mapbox/alpha-shake coming soon…

  52. github.com/mapbox/polysnap coming soon… my long-time nemesis

  53. github.com/mapbox/geobuf GeoJSON <–> compact binary lossless & freaking fast!

  54. github.com/mapbox/webgl-wind

  55. awesome job alert: GL Map Rendering Engineer grnh.se/7g6l4h1