Is it possible to show relations (for example traffic flow) between polygons (for example counties) by highlighting related polygons by doing a query on a start polygon using QGIS?
Here is an example: Blue polygons represent counties, delaunay-lines with arrow show traffic flow in one direction and (purple) desire-lines without arrow show total traffic flow.
What im doing so far: Flow lines or delaunay lines (created by aequilibrae plugin for qgis)
To explain the second picture: You do a query on the green polygon. The result is that related polygons get highlighted by the amount of traffic relations (red for a lot, yellow for not so much, blue for no traffic at all) to the green polygon.