Shared edges and reshaping

The Reshape Shared Edges tool allows you to reshape the shared edges of coincident polygon and polyline features without the restrictions of editing one pair of topology nodes at a time. This tool allows you to use either a selected polygon or set of contiguous polylines or digitize a new edit sketch line as the source for reshaping shared edges across nodes. Reshape Shared Edges improves productivity when reshaping shared edges and reduces time-consuming edits. It also ensures that features that need to be coincident remain coincident. For example, this tool can be used for reshaping a section of a coastline, and a set of coincident polygon and polyline features in various feature classes, in a single operation.

Reshaping features

Below are a few terms you should be familiar with when working with the Reshape Shared Edges tool.

• Reshaper features—Feature(s) that reflect the geometry used to reshape/update other features. Acceptable reshaper features are a single polygon (cannot be multipart or have interior rings), a single polyline or a set of contiguous polyline features, and a sketch feature digitized specifically for the operation. These features can be stored in the current database, in another database, or simply as shapefiles.
• Representative features—Features that are used to determine which shared edges are reshaped. These may be a polygon or a set of contiguous polyline features, except that you can select a multiringed polygon as long as the reshaper features only intersect one of the rings.
• Reshaping region—The part of the representative features to be reshaped by the reshaper features.
• Shared edges—Any linear part of a representative polyline or polygon feature's geometry that is coincident with another feature.
• Candidate features—The polyline and polygon features that are candidates for reshaping or clipping because they share edges within the reshaping region and with the representative features.

You can configure the behavior of the Reshape Shared Edges tool in two ways:

• Reshape Shared Edges Configuration dialog box—Controls what happens to candidate features
• Reshape Shared Edges window— Determines if a candidate feature is processed

The Reshape Shared Edges Configuration dialog box lists all the polyline feature classes, and their subtypes, in the current edit workspace. Features in checked feature classes/subtypes are cropped or deleted during processing; features in unchecked ones are reshaped. The default configuration is all unchecked, so all candidate features are reshaped. Check the check boxes for the feature classes and subtypes that you want to be cropped or deleted. You can optionally save these settings as your new default configuration.

For example, you might receive a new survey that indicates that the coastline has shifted. That survey may be contained in a shapefile. After adding the shapefile to the Table Of Contents window, you can proceed in one of two ways:

• You can use a coastline feature in the shapefile as your reshaper curve. You would leave the CoastlineL feature class unchecked in the Reshape Shared Edges Configuration dialog box so that those existing features would be reshaped.
• You could select a feature in the shapefile and copy and paste it into the CoastlineL feature class. You would check the CoastlineL feature class in the Reshape Shared Edges Configuration dialog box so that Candidate CoastlineL features would get clipped or deleted. You would then select the new CoastlineL feature to use as the reshaper curve. The tool clips or deletes any Candidate CoastlineL features it identifies rather than reshape them to overlap the new CoastlineL feature, leaving the new feature alone and reshaping all other features to conform to it.

Your configuration settings determine what happens to candidate feature classes and subtypes. Once you have selected your reshaper feature(s) and the tool has determined exactly which coincident features are candidates for reshaping, you can control which ones are processed and which are ignored by selecting/deselecting them in the tree view of the Reshape Shared Edges window. You can select or deselect

• Individual features
• Specific subtypes
• Entire feature classes by checking or unchecking the appropriate check box

Any features that are checked are processed according to the settings in the Reshape Shared Edges Configuration dialog box. For example, if you specified that a feature class should be clipped or deleted, those candidate features that are checked are clipped or deleted. Conversely, if you specified that the feature class should be reshaped, or the feature class is a polygon feature class, those candidate features that are checked are reshaped. Finally, regardless of the configuration setting, any unchecked features are ignored during the processing.