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How To: Digitize or create lines and polygons without clicking at every vertex

Summary

ArcGIS can digitize or trace features without mouse or puck-clicking using several options: streaming, tracing, or freehand drawing. With these methods, the mouse pointer is used to trace the desired feature.

Procedure

There are three options provided to do this: Digitize by streaming, Digitize by tracing, and Digitize by freehand drawing.

Digitize by streaming (stream mode digitizing)

Stream mode is often used while digitizing hardcopy maps on a digitizing board. Vertices are automatically added at different intervals as the pointer is moved.

  1. Start an edit session.
Note:
To specify the Stream Mode, click the Editor drop-down button > Options. This opens the Editing Options dialog box. In the Stream Mode field of the General tab, specify the Stream Tolerance (how far apart vertices are drawn) and Group (number of points removed from an Undo click) values. Click OK after editing.

For the Stream Tolerance, the map units of a data frame are determined by the coordinate system of the data frame. If the coordinate system is Geographic, the map units are in decimal degrees. The Stream Tolerance must be set to a very small number, 0.01 - 0.0001, depending on the map scale, for new vertices to be added when the mouse pointer is moved.
This is the Editing Options dialog box.
  1. Navigate to the Editor toolbar, and click the Create Features button. This opens the Create Features window.
  2. Select the layer to edit and specify the Construction Tools.
Note:
For the Digitize by streaming and Digitize by tracing methods, choosing only the Line, Polygon, or Auto Complete Polygon option from Construction Tools enables the Streaming function or the Trace tool.
  1. Right-click the map, and select Streaming.

    Select Streaming to enable stream mode digitizing.
  2. Move the pointer to digitize features.
Note:
Clicking on the map while streaming suspends the streaming session.
  1. To close the streaming session, right-click > Finish Sketch.
    Select Finish Sketch to complete digitizing session. Select Finish Part to complete one part of digitizing session.
  2. To complete one part of digitizing a feature, right-click > Finish Part. Click the map again to start digitizing another feature.

Digitize by tracing

Tracing is used to create a new feature which follow the shape of an existing feature. Tracing can be done by tracing directly over an existing feature or at an offset value.

  1. Start an edit session.
  2. Navigate to the Editor toolbar, and click the Create Features button. This opens the Create Features window.
  3. Select the layer to edit and the Construction Tools.
  4. Navigate to the Editor toolbar, and click the Trace tool. This is the Trace tool.
  5. Click the map, and start tracing by moving the pointer.
Note:
To specify the Trace Options, right-click on the map > Trace Options. This opens the Trace Options dialog box. For the Offset value, the default value is set to zero. This is to trace directly on top of an existing feature. Specify a different value to trace at an offset value. Check the Limit to length checkbox to specify the minimum length of tracing. Specify other settings, and click OK.
This is the Trace Options dialog box.
  1. To close the tracing session, right-click > Finish Sketch.
    Select Finish Sketch to exit the tracing session.
  2. To complete one part of digitizing a feature, right-click > Finish Part. Click the map again to start digitizing another feature.

Digitize by freehand drawing

Freehand drawing is used to create lines according to the movement of the pointer. The segments created are smooth and are not restricted by any features or boundaries on the map. This option is suitable for drawing quick, free-forming lines on the map.

  1. Start an edit session.
  2. Navigate to the Editor toolbar, and click the Create Features button. This opens the Create Features window.
  3. Select the layer to edit.
  4. For Construction Tools, select Freehand.
    Select the Freehand option in Construction Tools.
  5. Click the map, and start the freehand drawing by moving the pointer.
  6. Click the map once to stop the drawing session.

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