Last week we received a request for blog entry on a 3D effect we could provide for displaying building footprints using cartographic representations.
Representations for 3D drop-shadow
1.Once your building footprint data is in a geodatabase (required for cartographic representations) add it to ArcMap.
2.Set the symbol's outline width to 0.00 pts.
3.Right-click on the layer and choose Convert Symbology to Representation. I used the defaults setting for the representations.
4.Right-click (again) on the layer and choose Convert Symbology to Representation. I changed the Rule_ID field to RULE_ID_DS and the override field to OVERRIDE_DS ("DS" for drop shadow).
5.Clean up the TOC so that you have just a layer for the buildings representations that draws above a layer for the drop shadow representations.
6.Change the drop shadow representations to have a medium or dark gray or ground tone (depending on the colors in your map's background. You can also set the transparency (Display tab) to something like 50%.
7.For the drop shadow layer add the Move geometric effect and set the values to X Offset = 2pts and Y Offset = -2pts.
Here is what a larger portion of my map looked like:
One thing to be careful of is when you have very small buildings, a 2pt offset may be enough to cause the drop shadow to appear separate from the building. If that building is isolated, the effect won't look so good and the solution is to use a 1.5 or 1.2 pt. offset instead.
