How To: Create a shadow effect on a feature in ArcMap
Applying visual effects to elements on a map allows for distinction between foreground objects and background objects. When applied, this can visualize the primary object as an area of interest.
One of the main methods in figure-ground contrast is shadowing, or giving a 'drop shadow' effect to a figure. A drop shadow creates the impression that the feature is raised above the ground, drawing attention towards the primary object.
The instructions provided describe how to create a shadow effect for a shapefile feature in ArcMap. The Move geometric effect is used on a cartographic representation to create a drop shadow.
- Select the desired feature(s) via the Select Features tool.
- Right-click the feature class in the Table Of Contents, and click Convert Symbology to Representation.
Note: To execute the cartographic representation conversions, multipart polygons must be transformed into singlepart polygons via the Multipart To Singlepart tool. Refer to the following link for more information, ArcGIS for Desktop: Multipart To Singlepart.
- In the Convert Symbology to Representation dialog box, verify the parameters and click Convert.
Note: This tool is unavailable for ArcGIS for Desktop Basic licenses. To convert symbology into cartographic representations, it is recommended to maintain the data in a geodatabase. If the data exists outside of a geodatabase, the results of the conversion are output to the default geodatabase.
- Right-click the new feature class, and click Properties. In the Layer Properties dialog box, select the Symbology tab, and click the Color patch under 'Solid color pattern' to select the color of preference.
A hatch or gradient color pattern can also be used by clicking the right-arrow and selecting the desired pattern.
- Click the plus (+) symbol above the pattern menu to launch the Geometric Effects dialog box. Select Move, and click OK. Alter the X and Y offset accordingly ('5 pt' is a good example). Click Apply > OK.
- In the Table Of Contents, drag and drop the original feature class to the top of the list of layers. This provides the visual effect for the selected feature(s) of a drop shadow.
Note: To further increase the contrast between the primary object and the background, select a slightly darker shade.Besides shadowing, there are other figure-ground contrast methods to distinguish primary objects from secondary objects. Feathering visualizes primary objects by softening and blending the edges of the map. Refer to the following link for more information on feathering, ArcGIS Resources: Figure-ground: Feathering.
Whitewash is another method of figure-ground contrast where the entire map, except the primary object, is altered to appear slightly washed out. Refer to the following link for more information, ArcGIS Resources: Figure-ground: Whitewash.