Magnus Manske wrote:
Imagine this for the U.S.: If we had the border data for all counties, and want to draw a world map with the U.S. as a single entity, the county polygons would be fused into state polygons, which then would be fused into a few country polygons (continental, Hawaii, Alaska).
In my implementation, all data sets can carry meta information as well. The Danube in the example is painted in blue because it carries a "type:river" marker. Different object groups can be defined for different purposes (political, geographical, etc.) Also, objects can be labeled in all languages in-place. I currently don't show the labels, though.
Isn't this reimplementing some sort of a GIS data format and visualization system? I think there was at least one person on this list who claimed to have significant knowledge of the GIS field, and I know there are some open-source systems already available.
Stuff tends to get pretty complex as you go along: dealing with projections (since the earth isn't flat), 3d data, increasing/decreasing resolution as you zoom in/out, and even automatically placing labels.
-Mark