Indiemapper + Google My Maps
Posted by Andy on July 19th, 2010. 1 CommentGoogle Maps’ “My Maps” feature is a great way to create and view geographic data and annotations on Google’s base maps. But it’s also a great tool for generating the source data for simple but polished maps made with indiemapper.
While a lot user-generated content on Google Maps may seem to suffer pushpin fever, the tool can be purposed for nicer cartographic uses than maps of giant martini glasses, musical notes, and eight-balls. Google base maps can serve as an easy reference for accurately creating custom points and shapes, but may be too noisy for professional, published maps. Luckily, My Maps allows you to export your data to KML which can then be loaded into your handy web-based cartography application, indiemapper!
In this post is an example of how My Maps might be used for a basic overview map of America’s most famous road, Route 66.
Google Maps
Manually drawing Route 66 would be a tedious task with an awful lot of clicking. Google offers a huge advantage by allowing you to create a line that follows roads, using its routing algorithms. Route 66 roughly follows modern interstates from Chicago to Los Angeles. Google wants to use a different route directly between the two cities, but an intermediate click around Albuquerque ensures that it’ll follow the correct southern route.
My final map is meant to appear at a fairly small size, perhaps the width of a couple of columns in accompaniment of a newspaper article. As such, minor deviations of the interstates from Route 66 are not of much concern because of the small scale. However, in certain spots where the difference is notable, such as in western Arizona, I can click and drag the route to conform to the correct road.
Besides the actual path I’ll want to indicate some of the larger cities along Route 66 using basic placemarks. It would be okay to use crazy helicopter or snowflake icons here, but that garish fun won’t be carried over to indiemapper.
That’ll do for now. To export to KML, I save the map and click the “View in Google Earth” link. The KML file that is generated actually only contains a “network link” to a location on Google’s servers. In my experience this means that loading this KML file will always show the latest version of the map as saved on My Maps, no matter when the file was downloaded.
Indiemapper
As the KML from Google Maps will only contain the custom point and line data that I created, my indiemapper map will need a base map. Natural Earth Vector data from indiemapper’s shapefile library is perfect for the job. I’ll add countries, states and provinces, and lakes and reservoirs.
Then after loading the KML and a bit of styling work, everything is in place.
Everything, that is, except labels. I want city and state labels. After choosing to add a layer in the usual manner, the label options for the KML data source are two. name_kml is the titles of lines, placemarks, and shapes—in this case, the cities. Note that the only choices in this panel are for labels and reference layers. For most other data sources there would be options for single and multivariate thematic layers. KML exported from Google Maps contains only text attributes and no numeric values on which to base any thematic layers.
After adding labels for NAME on the States and Provinces layer, I edit the styles and placement of all the labels in the page. I’m going with the Geochet (Georgia + Trebuchet) template for the city and state labels. I don’t need the “Route 66″ label that appeared for the line because that will simply be the title of the map, so I can just drag it off the page and out of view, using the Annotation layer for the title instead.
There. A very simple overview map of Route 66. If you’d like to investigate further, check out the IMP file for this map, the KML source, or the original data in Google Maps.
Final thoughts
Google My Maps tools are geared toward miscellaneous features with names and descriptions, and it is difficult to organize this map data into real thematic content that taps into the strengths of indiemapper. However, Google Maps is ideal for generating simple geodata quickly. I think of two sides to the way indiemapper and Google Maps can work together: Google Maps is a way to add custom data to indiemapper, and indiemapper is a way to add certain custom styles to Google Maps data. For the former, KML from Google Maps may not provide sophisticated thematic data, but it’s great for easily creating ancillary information or features for very simple maps. As for the latter, indiemapper’s built-in reference and thematic data, as well as its projection and export capabilities, offer an alternative base style to Google base maps which are not suitable for every purpose.











































