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Shadow settings for line features

May 20 2009 | 0 comments
Categories: Cartographic Representations, Symbology

I would like to know if there is any way (apart from duplicating the line) to make shadowed lines out of polyline features. When I try with simple symbology, I duplicate the line and offset it. However, this doesn't always work well depending on the way the original feature was digitized. Plus, I would also like to have some control on the shadow, such as transparency, gradient fill, etc.
Thank you.

Mapping Center Answer:

It depends on how prominently the line features and their drop-shadows are in your map.  If these lines are the most important information theme on the map, then duplicate the line.  Drop-shawdows for lines is an easy concept to understand, but very difficult to deliver. 

The standard symbology, with a two-layer symbol isn't suitable for much from a cartographic quality perspective. It will do when the lines are just part of the background context for a map, and not prominent.

Cartographic representations offer a middle ground.  The offset symbology there is pretty good, but it doesn't handle complex line features (lots of relatively intricate geometry at the map's scale) well.

It's often best, if appropriate given the kind of data you have and it's role on your map, to simplify the data, but only slightly, with the intent of removing unnecessary intricacy from the data. You may need to do some hand-editing to repair damage the simplification tool does, because it is indiscriminate about which vertices get removed--often removing vertices that provide "defining character" for a given shape.

So, if you need high quality presentation for prominent line features, first, if possible try the simplification in combination with representations.  That will be faster.  Otherwise manually offsetting a copy of the data is the only way to achieve this effect with an ultra-high level of quality.


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