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


ArcGIS can digitize or trace features without mouse or puck clicking by using stream mode digitizing. With this method, the mouse pointer is used to trace the desired feature. Minimum distances between vertices are set on the Editor Options dialog box.

Stream mode is often used while digitizing hardcopy maps on a digitizing board, but it can also be used for heads up digitizing or freehand sketching of features.


Stream Tolerance, or how far apart the vertices will be, and Group, or how many points will be removed from an Undo click, must be set before digitizing in stream mode.

  1. Start Editing.
  2. Click Editor from the ArcMap Editor toolbar and then click Options.
  3. On the General Tab, set the Stream Tolerance in the Map Units, not the Display Units, of the Data Frame and Group, then click OK.

    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 will be Decimal Degrees. The Stream tolerance needs to be set very small, 0.01 - 0.0001, depending on the map scale, in order for new vertices to be added when the mouse pointer is moved.

  4. Select the sketch tool
    [O-image] ArcMap Editing Sketch tool
    and click the first point to start tracing. Move the pointer slightly away from the initial point, right-click and select streaming, or press the F8 key.
  5. Left-click again and trace the line.
  6. Right-click to Finish Part (or to Finish Sketch) when done tracing, or press F8 again to exit streaming mode and use the other sketch construction tools.
    The sketch can also be finished by double-clicking.