6.2 Feature Modification Tools

Feature Modification Tools

Modifying existing vector features is a core component of GIS data maintenance in Esri ArcGIS Pro. Whether adjusting administrative boundaries, updating utility line networks, or updating parcel geometry, GIS professionals must select and configure appropriate editing tools. ArcGIS Pro consolidates geometric editing workflows inside the Modify Features pane, accessible from the Edit tab. Mastering these tools—ranging from basic splitting and merging to advanced vertex editing and topological edge alignment—is essential for passing the ArcGIS Pro Foundation certification exam.

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The Modify Features Pane Architecture

The Modify Features pane organizes geometry modification tools into specialized task categories. Editors can filter tools using a text search box or pin frequently used tools to a Favorites tab for immediate access.

+-----------------------------------------------------------------------+
| Modify Features Pane                                                  |
|-----------------------------------------------------------------------|
| [ Search tools (e.g., Split, Reshape)...                            ] |
|                                                                       |
|  v Core Edit Tasks                                                    |
|    > Reshape           > Split             > Merge                    |
|    > Edit Vertices     > Extend/Trim       > Clip                     |
|                                                                       |
|  v Alignment Tasks                                                    |
|    > Align Features    > Align Edge        > Move                     |
|                                                                       |
|  v Construction Tasks                                                 |
|    > Construct Polygons                    > Duplicate Geometry       |
+-----------------------------------------------------------------------+

Workflow Execution Model

Editing operations within the Modify Features pane typically follow a two-step pattern:

1. Feature Selection: Select one or more target features using the interactive Selection tool or Map view context selection.
2. Tool Execution: Activate the desired tool, configure tool parameters or sketch replacement geometry, and click Apply or press F2 to execute the modification.

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Feature Division & Combination Tools

Split Tool

The Split tool divides an existing polyline or polygon feature into two or more independent features:

• Interactive Sketch Split: Editors draw a split line across the selected feature; the feature divides along the intersection of the sketch.
• Split by Distance / Percentage: Divides polylines at a specified distance from the start vertex or at proportional percentage intervals.
• Attribute Handling: When a geodatabase feature is split, attribute domains govern how values are apportioned. Range domains follow their assigned split policy (Duplicate, Default Value, or Ratio), while coded value domains typically duplicate original values unless rules dictate otherwise.

Merge Tool

The Merge tool combines two or more selected features belonging to the same feature class into a single feature:

• Target Attribute Selection: The editor explicitly chooses which feature's attribute values are preserved in the final output record.
• Multipart Geometry Options: Non-contiguous features can be merged into a single multipart feature, where multiple spatial components share a single entry in the attribute table.

Merge Operation Workflow:
[ Feature A: Pipe_ID=101, Dia=8" ]  +  [ Feature B: Pipe_ID=102, Dia=8" ]
                                | 
                                v
             [ Select Target Record: Keep Pipe_ID=101 ]
                                | 
                                v
           [ Merged Single Feature: Pipe_ID=101, Combined Length ]

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Geometric Adjustment & Boundary Editing Tools

Reshape Tool

The Reshape tool replaces a portion of a selected line or polygon boundary with a newly sketched line.

• Intersection Rule: The replacement sketch line must cross the original feature boundary at least twice (for polygons) or cross a polyline feature to establish clear entry and exit points.
• Execution: The portion of the original boundary between the intersection points is deleted and replaced with the new sketch path upon completion.

Extend and Trim Tools

• Extend Tool: Modifies polyline features by extending their endpoint along their trajectory until they intersect a designated boundary line or adjacent feature.
• Trim Tool: Cuts back overshooting polyline segments that cross past a designated boundary line, removing unwanted dangle segments.

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Spatial Alignment & Connectivity Tools

Maintaining topological consistency across coincident layer boundaries is vital for clean GIS databases.

+-----------------------------------------------------------------------+
| Alignment Tools Comparison                                            |
|-----------------------------------------------------------------------|
| Tool           | Primary Target      | Behavior                       |
|----------------|---------------------|--------------------------------|
| Align Features | Multiple Layers     | Adjusts selected features to   |
|                |                     | match an aligned sketch line.  |
|----------------|---------------------|--------------------------------|
| Align Edge     | Shared Topology     | Moves a shared topological edge|
|                | Edges               | and snaps coincident features. |
+-----------------------------------------------------------------------+

Align Features Tool

The Align Features tool adjusts features within a specified buffer distance to match a newly drawn alignment path. It is commonly used to adjust legacy vector data to updated high-resolution aerial imagery without manually editing individual vertices.

Align Edge Tool

The Align Edge tool operates on map topology or geodatabase topology edges. When an editor selects a topological edge and sketches a new path, all coincident feature boundaries sharing that edge are automatically updated in unison, preventing gaps or overlaps.

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Construct & Clip Tools

Construct Polygons Tool

The Construct Polygons tool creates new polygon features from closed areas bounded by selected line features or intersecting polygon boundaries. Editors specify the target polygon layer and template, allowing rapid polygon generation from line networks (e.g., creating land parcels from street centerlines).

Clip Tool

The Clip tool trims or cuts features based on the spatial extent of an overlapping input polygon geometry:

• Discard Area of Overlap: Removes portions of target features falling inside the clip polygon.
• Preserve Area of Overlap: Retains only portions of target features falling inside the clip boundary, deleting outer areas.
• Clip All Intersecting Features: Applies clipping across all selectable layers intersecting the clipping geometry.

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Edit Vertices Tool & Segment Conversion

When precise micro-adjustments are required, the Edit Vertices tool provides direct control over the structural geometry of a vector feature.

+-----------------------------------------------------------------------+
| Edit Vertices Pane Controls                                           |
|-----------------------------------------------------------------------|
| Vertex Table:                                                         |
| Index | X Coordinate  | Y Coordinate  | Z Elevation | Segment Type    |
| 0     | 542100.12     | 4120500.45    | 120.5       | Straight        |
| 1     | 542145.88     | 4120530.10    | 121.0       | Bezier Curve    |
| 2     | 542200.00     | 4120580.00    | 121.5       | Circular Arc    |
|-----------------------------------------------------------------------|
| Actions: [ Add Vertex ]  [ Delete Vertex ]  [ Move Relative ]         |
+-----------------------------------------------------------------------+

Vertex Editing Operations

• Insert Vertex: Adds a new vertex along a feature segment when right-clicking or using the vertex toolbar.
• Delete Vertex: Removes an existing vertex, causing adjacent segments to bridge directly.
• Move Vertex: Interactively drags a vertex or updates its numeric X, Y, and Z coordinates directly in the Edit Vertices pane table.
• Change Segment Types: Right-clicking a segment allows converting straight lines to Bezier curves (adjusting tangency and curvature handles) or circular arcs (adjusting radii points), providing smooth geometric representations for CAD integration or curb digitization.