Creating features with the Vectorization Trace tool

The Vectorization Trace tool is designed for tracing connected raster cells. Place the tool at an appropriate start location in the raster and click to begin the tracing process. The Vectorization Trace tool automatically follows the centerline of the raster cells based on the direction in which you point the tool's arrow and subsequently generates vector features.

Using raster snapping in conjunction with the Vectorization Trace tool is highly recommended. However, it is not necessary. The Vectorization Trace tool recognizes contiguous raster cells on its own and creates features without the use of raster snapping properties.

The Vectorization Trace tool works by following along the middle or centerline of a series of connected raster cells. When you click the tool, a cursor appears that is similar to the standard edit sketch cursor. Once you snap to a location or place your pointer over a raster cell, click to begin the trace. The Vectorization Trace tool creates features along a raster linear element until it reaches the end of the raster linear element or encounters a raster intersection.

Depending on the current vectorization settings, the location and number of vertices in the line feature vary. You can change these settings via the Vectorization Settings dialog box to improve the outcome of the tracing. Raster cells that are ignored during tracing could be exceeding the maximum raster line width setting.

Once you have finished tracing, press F2 to finish the sketch.

Steps:

1. These steps can be used to create lines or polygons:
   • To create lines, click a line feature template in the Create Features window.
   • To create polygons, click a polygon feature template in the Create Features window.
2. Click the Vectorization Trace tool on the ArcScan toolbar.
3. Snap to a location in the raster layer.
4. Click to activate the Vectorization Trace tool.
5. Point the tool's arrowhead in the direction you want to trace.
6. Click to start tracing. The Vectorization Trace tool automatically creates vertices based on the current vectorization settings.
7. If you encounter an intersection, the Vectorization Trace tool stops. Point the arrow in the direction you want to vectorize and click to continue tracing.
8. Press F2 to finish the sketch when you have reached the end of the raster line or the start point of the sketch.