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

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hello, friends!

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

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github.com/mourner/rbush

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box queries

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ﬁnding nearest neighbors

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• 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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• 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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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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github.com/mapbox/tile-reduce

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osmlab.github.io/osm-qa-tiles

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tile-reduce

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which polygon?

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github.com/mapbox/which-polygon

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github.com/mapbox/linematch

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buffer, union, difference: slow

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github.com/mapbox/linematch freaking fast

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github.com/mapbox/lineclip freaking fast

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github.com/mourner/rbush-knn

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distance from a point to a bounding box

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distance from a segment to a bounding box

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github.com/mapbox/concaveman

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github.com/mapbox/concaveman

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github.com/mourner/kdbush

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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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github.com/mapbox/supercluster

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github.com/mapbox/supercluster

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geodesic nearest neighbors?

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

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bbox on a sphere

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convert to 3D coords?

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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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when you found a use for differential math for the ﬁrst time in a 13-year career

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github.com/mourner/geokdbush

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measuring distances fast

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measuring distances fast

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euclidean geometry with lat/lon

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euclidean geometry with lat/lon

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