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

JSGeo 2017, August 15th

Transcript

1. hello, friends!
   

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3. random cool stuff
   I’ve been hacking on
   JSGeo, August 15th 2017
   Vlad
   (mostly spatial indices)
   

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4. github.com/mourner/rbush
   

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5. box queries
   

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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
    

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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
    

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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
    

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14. github.com/mapbox/tile-reduce
    

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

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16. tile-reduce
    

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17. which polygon?
    

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18. github.com/mapbox/which-polygon
    

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19. github.com/mapbox/linematch
    

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20. buffer, union, difference: slow
    

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21. github.com/mapbox/linematch
    freaking fast
    

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22. github.com/mapbox/lineclip
    freaking fast
    

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23. github.com/mourner/rbush-knn
    

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24. distance from a point to a bounding box
    

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25. distance from a segment to a bounding box
    

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26. github.com/mapbox/concaveman
    

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27. github.com/mapbox/concaveman
    

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28. github.com/mourner/kdbush
    

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29. github.com/mourner/kdbush
    •supports points only (not boxes)
    
    •can’t add/remove points dynamically
    
    •indexing is 5–8 times faster
    

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30. github.com/mapbox/supercluster
    

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31. github.com/mapbox/supercluster
    

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33. geodesic nearest neighbors?
    

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34. distance from a point to a bounding box
    on a sphere?!
    

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35. bbox on a sphere
    

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37. convert to 3D coords?
    

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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
    

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43. github.com/mourner/geokdbush
    

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44. measuring distances fast
    

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45. measuring distances fast
    

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46. euclidean geometry with lat/lon
    

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47. euclidean geometry with lat/lon
    

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48. github.com/mapbox/cheap-ruler
    •distance
    
    •bearing
    
    •destination
    
    •lineDistance
    
    •area
    
    •along
    •pointOnLine
    
    •lineSlice
    
    •lineSliceAlong
    
    •bufferPoint
    
    •bufferBBox
    
    •insideBBox
    freaking
    fast!
    

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49. github.com/mapbox/earcut
    

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50. github.com/mapbox/delaunator
    

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

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

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

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54. github.com/mapbox/webgl-wind
    

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

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