Thursday, March 8, 2007

Welcome to Census KML!

A couple of days ago my wife asked me to help her map some Census data. I have always been interested in maps, and after a couple of web searches, I found a couple of interesting examples of people using Google Earth to map data. In particular, I found this post on the Juice Analytics blog. This got me going - I had some spare time, a desire to learn Ruby, a lot of data, a love of data visualization, and a purpose.

I plan to use this blog to share what I've created and let others share their knowledge, feedback, and experience. Please join in the discussion and check back frequently as I hope to share what I've found.

This wouldn't be much of a start if I didn't share some of the progress I've been making. The following screen shot shows the 2000 Census population by County Subdivision data where each meter of height represents 10 people. [There is also coloring, but I've found what appears to be a bug in Google Earth such that it doesn't properly draw colors for 3D polygons.]

1 comment:

Anonymous said...

Interesting take on KML mapping.

Quick notes: GE needs polygon coordinates in counter-clockwise order to display colors correctly. Typically, ESRI shapefiles store polygon coordinates in clockwise order.

Also, polygon rendering really taxes the end-user's graphics card. Judging from your screen-shots, you have a pretty stout card on your machine. But something to keep in mind as you distribute your content more broadly.

Looking forward to seeing more,

Brian Timoney