This video explains the basics of Turf.js. Turf.js is a spatial analysis library for JavaScript. You can use Turf.js in web mapping applications to create buffers, intersect and union polygons, dissolve on attributes, perform spatial joins, and much more. Continue reading “Spatial Analysis in Leaflet using Turf.js”
Filtering data in Leaflet
This video shows an example of how to filter data in Leaflet using HTML radio buttons to make a selection. This is analagous to using a definition query in ArcGIS or a filter feature in QGIS. We are limiting which data is included in a feature group based on its attributes. Continue reading “Filtering data in Leaflet”
Displaying YOUR GIS data in a leaflet map (pt 2 – lines and polygons)
This video shows how to load your line and polygon GIS data into a leaflet web map, This requires using the Leaflet.Ajax plug-in. I also demonstrate the basics of styling and filtering line and polygon data. Continue reading “Displaying YOUR GIS data in a leaflet map (pt 2 – lines and polygons)”
Displaying YOUR GIS data in a leaflet web map (pt 1- Points)
This video shows how to export your GIS data to a GeoJSON text file and load it into a leaflet web map, This requires using the Leaflet.Ajax plug-in. I also demonstrate the basics of styling and filtering point data. Continue reading “Displaying YOUR GIS data in a leaflet web map (pt 1- Points)”
Client Server Architecture for Web GIS
How is programming for the web different than programming for a single computer?
If you want to create web GIS applications you need to understand the basics of client-server architecture
What does the client do?
What does the server do?
How do the client and server communicate?
What implications does all of this have for web GIS applications?
What is GeoJSON and why should you care?
GeoJSON is a core technology in web GIS. It allows vector data to be stored in a text-based format that is easily handled in JavaScript, sent across the internet, or stored in a database (including web storage). Continue reading “What is GeoJSON and why should you care?”