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display overlapping bus lines

September 01 2008 | 0 comments
Categories: Cartographic Effects, Cartographic Representations, Symbology

Hi, I am a planner reviewing the bus lines in my city. Currently, we have all the bus routes set up on ArcGIS, but when we display them, we can't do so clearly for those lines that overlap because they share the same center lines. Is there some solution that can automate the offsetting of bus lines when two or more overlap? We do not wish to "hardcode" the position of the bus lines in an offset position because we can have up to 20 lines through a corridor, and depending on our analysis, we may sometimes display all 20, or just 1, 2, or some other number of routes. Thank you!

Mapping Center Answer:

Unfortunately there's no way to dynamically display (i.e., not hardcode) your routes such that there are no offsets.  From a cartographic perspective, that's something of a holy grail.

We did a blog entry some time ago on a method to produce decent looking offset routes called, Create route maps with the ArcGIS Schematics extension.

I would suggest using the ArcGIS Schematics solution, at a minimum, for the scenario with all 20 routes.  The problem with not using it is that the generic symbol offset property is just a hard one-direction offset and won't respect the idea of route direction.

So, the only other solution is to use cartographic representations for your scenarios with fewer routes where you can edit the representation geometry (by selecting just a subset of vertexes and moving them parallel), which for simple maps will be faster--but for any complex maps, even with just 4 or 5 routes, it will be faster to use the Schematics-based solution.

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