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Scale bar with custom units (18th century Swedish Miles), are they possible?

October 01 2007 | 0 comments

I want to create several scalebars in a single map layout. Some of them need to have units that
are not supported in ArcMap. For instance, one of the scalebars needs to be in 18th Century German miles (25,000 feet), another needs to be in 18th Century Swedish miles (32,577 feet), and yet another in Leagues (15,840 feet). Do you have a good idea about how to do this? Is there a way for me to define new reference units in ArcGIS so that these units will be available for any new projects I want to create?

Mapping Center Answer:

You’ll have to do this manually based on a conversion factor from one of the units we do support. The idea would be to create a scalebar using the modern units but with the interval set to a value that includes the conversion factor. Then convert it to graphics and change the text.

If this is something that you run into frequently, it is possible via ArcObjects to implement new classes of units and add them to your local system. Each unit we support now is implemented as it’s own object class that implements the IUnit COM interface. I doubt it is a trivial programming task—I’ve never heard of anyone undertaking it.

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