Plotting Country Capitals on Raphael World Map
You can read more about geographic coordinate conversion on Wikipedia but the Raphael World Map example already had a DMS to Decimal Degree conversion function in there so I have extracted it into my own online geo-coordinate conversion tool. This way, I can handle data that presents coordinates with degrees, minutess, and seconds instead of just decimal degrees.
In terms of finding geo coordinates of all the country capitals, there are several good sources, but I decided to retrieve this data from World Bank since they have an API. Instead of writing an Ajax request, I just pulled the JSON with all country information, parsed out the capital city geo coordinates, and converted them into an inline array.
After that, I cleaned up the original Raphael World Map example and plotted all these capital cities on the Map. Check out the demo and take a look at the source.
As a next step it would be nice to add zooming into the map and label the capitals or show the names in a tooltip. There are many Raphael plugins for zooming and you could even implement a standalone SVG zooming library. In terms of tooltips, you could use this jsfiddle or something more fancy like this Raphael SVG Tool Tip extension, but this is beyond the scope of my simple Raphael World Map example.
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