Draw or select an existing 2D closed CAD object whose shape and size you want to use as a template for the extraction, and then either manually or automatically select features in a point cloud of the same shape and size (for example, painted arrows on a roadway) and create a closed polyline around each. You can select whether or not "found" features may be rotated or mirrored (flipped) from the selected shape's orientation.

Following are the basic steps for this workflow. For more detailed instructions, see Extract Geometry from a Point Cloud.

Steps:

Commands:

1.

In the 3D View or Plan View, display the scan points from which you want to extract geometric objects. Try to avoid making changes to the view after the Extract Geometry command is running.

3D View

Plan View

2.

Select the Extract Geometry command.

Extract Geometry

3.

In the Extraction type group box, select the appropriate extraction option:

• Single - Extract geometric objects from a point cloud individually as you select them.
• Multiple - Extract all of the matching geometric objects in a selected area.

4.

If you selected the Single extraction option:

1. Select an existing CAD shape you want to user for an extraction template, or create a new one using the Create Polyline command.
2. If applicable, check the Include mirrored shape check box and/or Include rotated shapes check boxes.
3. Optionally, select a different layer for the extracted geometry, or create a new layer using the Manage Layers command.
4. Do either of the following:
   • To extract geometry without first verifying the results, check the Create geometry automatically check box, click in the Pick a point field, and then, in a graphic view, click on a feature matching the template whose geometry you want to extract. Click Extract. Repeat as necessary.
   • To extract geometry only after verifying the results, uncheck the Create geometry automatically check box, click in the Pick a point field, and then, in a graphic view, click on a feature matching the template whose geometry you want to extract. (If necessary, use the Intensity threshold slider control to fine tune the intensity for better results.) Click Extract.

     If the feature matches the shape template as expected, click the Add button to complete the extraction. Otherwise, click the Discard button to remove it. Repeat as necessary.

Create a Polyline

Layer Manager

5.

If you selected the Multiple extraction option:

1. Select an existing CAD shape you want to user for an extraction template, or create a new one using the Create Polyline command.
2. If applicable, check the Include mirrored shape check box and/or Include rotated shapes check boxes.
3. Do either of the following:
   • If a polygonal border already exists in your project around the area from which you want to extract geometry, click in the Select the area of extraction field and select it in the graphic view.
   • If an applicable polygonal border does not already exist in your project, click the Create Area button to display the Create Polygon command pane. Then, create a polygon of the desired shape and size to encompass the area from which you want to extract geometry.
4. Use the Intensity threshold slider control to adjust the intensity of the point cloud as necessary to best delineate the shape of the features to be extracted.
5. Optionally, check the Delete the area shape after extraction check box.
6. Click Extract.
7. If the results are not satisfactory, try either or both of the following:
   • Use the Intensity threshold slider control to change the Intensity threshold level and re-run the extraction.
   • Use the Confidence slider control to adjust the extraction Confidence level, possibly identifying more matching shapes, or less.
8. Optionally, select a different layer for the extracted geometry, or create a new layer using the Manage Layers command.
9. Click the Add button.

Create a Polyline

Layer Manager

Create a Polygon