Web Mapping Services Overview (2/7)

Part 2: Tile Maps and APIs

Say you’re playing around on Google Maps. You click and hold your mouse button to magically drag the map around from Timbuktu to Connecticut. Then you zoom in on Schenectady until you can see your cousin’s car parked in his driveway and his kid playing with his dog in the yard. You might not think much of it now, but let’s remember that all of this was novel just a few years ago. This new (circa 2005) sort of interface is called a slippy map. Continue reading


Web Mapping Services Overview (1/7)

Part 1: What is a WMS?

A Web Map Service (WMS) is an OGC (Open Geospatial Consortium) specification that “defines a common interface for disseminating digital maps, rendered from spatial data, across the Internet. WMS supports the networked interchange of web based map layers, which are generally rendered in a digital image such as JPEG, GIF, PNG, etc.”1

In English, a WMS is computer language (script) that tells a server, “gimme your map!” The server then responds by sending an image file to your (the client’s) browser (e.g., Firefox, etc.). It is important to note that a WMS is not a map mash-up or a slippy map, which are increasingly the norm of interactive web maps made for public consumption. For information on how those work, see Part 2. Continue reading

Technology Research Memo 2: ArcGIS Online

TYPE: Applications


LANGUAGE: MapViewer: JavaScript; Explorer: Silverlight

REFERENCE MAP SUPPORT: Toggle Map Type (1), Custom Vectors (1)

THEMATIC MAP ISOMORPHS: Choropleth (1), Proportional Symbol (1), Graph/Chart (1)

CARTOGRAPHIC INTERACTIONS: Reexpress (1), Arrange/Linked Views (1), Sequence/Animate (2), Resymbolize (1), Overlay/Toggle Layers (1), Pan (1), Zoom (1), Retrieve (1), Calculate (1)

OTHER ISSUES: Requires a free account to use. Good documentation and full tutorial. Functionality continues to be updated.

WEBSITE: www.arcgis.com

DOCUMENTATION: http://help.arcgis.com/en/arcgisexplorer/help

EXAMPLES: Links in Gallery: http://www.arcgis.com/home/gallery.html Continue reading