handle big polygons

[bbest]

Efficiently handle many/big polygons with WMS and SLD in GeoServer.

Use GeoServer to efficiently handle many/big polygons with many vertices so GUI doesn't send individual vertices to client, which for polygons with many vertices becomes unwieldy and slow. The fastest way I know is to overlay a WMS png, which could be styled with a style layer descriptor (SLD).

• Publishing a PostGIS table — GeoServer 2.13.x User Manual
• wms - Can I do custom styling on GeoServer - Geographic Information Systems Stack Exchange
• Polygons — GeoServer 2.12.x User Manual

[bbest]

Shiny alternative:

• Render large spatial datasets in shiny leaflet · Issue #38 · ropensci/auunconf
• leafier/leaflet_test at amy-jeff-dev · ropenscilabs/leafier
  • server_simplify.R: subset and simplify based on input$map_bounds

[bbest]

Vector Tiles

Leaflet Vector Tiles // Speaker Deck

• SpatialServer/Leaflet.MapboxVectorTile: A Leaflet Plugin that renders Mapbox Vector Tiles on HTML5 Canvas.
• Leaflet/Leaflet.VectorGrid: Display gridded vector data (sliced GeoJSON or protobuf vector tiles) in Leaflet 1.0.0
• Leaflet – OpenMapTiles
• spatialdev/PGRestAPI: Node.js REST API for PostGres Spatial Entities. AKA: Chubbs Spatial Server
  • Create Mapbox Vector Tiles on the fly from PostGIS or shapefiles. more...
  • Serve pre-created Vector Tiles .mbtiles files
  • Serve pre-created PNG .mbtiles files (like TileStream)
  • REST API for querying Postgres tables - Supports spatial intersection, tabular queries and aggregation queries
  • REST API returns GeoJSON, CSV, Shapefile or esriJSON
  • Templates for creating custom web service endpoints - (Execute custom SQL functions, for example)
  • Rasters in PostGIS offer basic intersect operations and zonal stats. Find sum of raster values that intersect a polygon, for example.

rstudio/leaflet migrating 0.7 to 1.2

NOTE: RStudio/leaflet is still on leaflet 0.7, which does not support vector tiles, but close to migrating...

• Upgrade LeafletJS to 1.x · Issue #357 · rstudio/leaflet
• Upgrade to Leaflet v1.x by jcheng5 · Pull Request #453 · rstudio/leaflet
• update markercluster->v0.1.1, leaflet-measure->2.1.7, leaflet-omnivore->0.3.4 by timelyportfolio · Pull Request #458 · rstudio/leaflet
• Commits · bhaskarvk/leaflet
• bhaskarvk/leaflet at upgrade/leaflet-v1.x

Red Cross Example

https://github.com/AmericanRedCross/GeoForce

This is the front-end JavaScript application that utilizes AngularJS, Leaflet, and Bootstrap.

[bbest]

GeoServer Vector Tiles

• Vector tiles tutorial — GeoServer 2.13.x User Manual

var style_highlighted = new ol.style.Style({
   fill: new ol.style.Fill({
     color: 'yellow'
   }),
   stroke: new ol.style.Stroke({
     color: '#880000',
     width: 1
   })
 });

//...

 function simpleStyle(feature) {
   if (feature.get("region_un") == "Africa") {
     return style_highlighted;
   }
   return style_simple;
 }

Vector tile output with Africa highlighted

[bbest]

working

• added support for TMS layer, used by Geoserver layers by stefanocudini · Pull Request #71 · SpatialServer/Leaflet.MapboxVectorTile

• Leaflet.MapboxVectorTile/configuration.md at master · SpatialServer/Leaflet.MapboxVectorTile

  • Leaflet Vector Tiles // Speaker Deck

• load server software, a la MBON in a Box, using docker, RStudio Server, Shiny... · Issue #4 · marinebon/sdg14

  • GeoServer: Install Map Vector Tiles
  • GeoServer: Enable CORS in GeoServer

• commit 199922b#diff-5e15f604c40ccd66afb0ce7e9d2d44f5 - MapBoxVectorTiles for Summit test app working: vectortiles/app.R

other

• openlayers/vector_tiles.R at master · crazycapivara/openlayers

[bbest]

t-rex

http://t-rex.tileserver.ch/
Create and serve your own vector tiles

Serve vector tiles

• Live tiles from PostGIS databases and GDAL vector formats
• Zero-configuration mode
• Embedded webserver
• Visual styling with Maputnik

Generate vector tiles

• Tile generation command with simple parallelization
• Generate configuration template
• Support for custom tile grids

Easy to Use

• Auto-detection of layers in database
• Single human readeable configuration file
• Automatic reprojection to grid CRS
• Install package or run in a Docker container

[bbest]

MapZen Vector Tiles

This likes the way to go in future:

Vector Tile Service · Mapzen:

The Mapzen vector tile server uses the familiar slippy tile zoom/x/y URL format:

http://tile.mapzen.com/mapzen/vector/v1/{layers}/{z}/{x}/{y}.{format}?api_key={api_key}

Note: uses standard {y}, not {-y} like GeoServer, which means don't need {-y} tms hack in Leaflet.MapboxVectorTile like I implemented in https://github.com/bbest/leaflet.extras.

Mapzen Pricing:

MAPS - Vector tiles & display

• $0: 50,000 requests/month
• 5¢: per additional 1,000 requests

Documentation

• Vector Tile Service
• Make a map - Vector Tile Service

Setting up your own MVT Server

• mapzen/d3-vector-tiles: Adapting d3.geo.tile to show Mapzen vector tiles
• Serving Vector Tiles - Paul’s Blog
• tilezen/tileserver: A lightweight tileserver to share code paths with tilequeue for tile generation.
• Mapzen Vector Tile Service · tilezen/vector-datasource Wiki