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The FOSS4G Map by Jason Sanford of Ubisense
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The foss4g Map
or ...
how many open source geo tools can I useto create a simple web map
mobile edition
mobile edition
mobile edition
mobile edition
•Yet another slippy map API, but options are good
•Very active development, bug fixes
•Polymaps/jQuery-like object chaining•my_map.addLayer( my_layer ).setView( new L.LatLng( 39.741, -105.011 ), 18 );
•Open Source BSD-licensed
•Use it behind the firewall, in disconnected environments
Map Tiles =
MapQuest OSM Tiles
+
Custom Tiles
OSM Based Tiles Open Aerial Tiles
•From my experience, updated almost instantly•Great cartography•Free to use•just attribute MapQuest and OSM contributors
what about these?Custom overlay tiles also OSM based
osm2pgsql
Geofabrik offers OSM downloads that are updated daily ...
... cut down to the state level in the US.
We use the data loaded into PostGIS for:•map tile creation•map feature selection
For more information on PostGIS,see the 54 other talks during this conference
Browser based web map design studio
Changes to map styles are visible immediately, not after a test run
Pan and zoom the map like any other slippy map to see scale
dependent changes
Multiple data source options like PostGIS, GeoJSON, shapefile, KML,
GeoTIFF, SQLite
Easily set tile export extent
Tile Exports
Adjust zoom levels to export and view immediate change in tile
count
No more accidental 4 million tile jobs
TileMill Exports = MBTiles file
Tiles are stored in a single file, not thousands (or millions), making them much more portable
MBTiles files are simple SQLite databases
MBTiles files can be served a few different ways
mbutil
MapProxy
Feature Selection
var marker = new L.Marker( new L.LatLng( 39.74, -104.98 ), { icon: new Foss4gIcon()} );
marker.bindPopup( “<h2>The Conference</h2>....” );
Feature Selection
map.on( “click”, handleMapClick );
function handleMapClick ( event ) { var lat = event.latlng.lat; var lng = event.latlng.lng; $.getJSON( “select?lat=” + lat + “&lon=” + lng + “&zoom=” + map.getZoom(), handleResponse );}
function handleResponse ( data /* GeoJSON FeatureCollection */ ) {// Pass GeoJSON Feature(s) to instance of L.GeoJSON (GeoJSON layer) to create markers or lines// Populate Information panel with feature type/name and appropriate image (fork and knife)}
