About Performing the Squaring of Traced Outlines

When extracting appropriate objects such as buildings, the traced outlines may be squared using an orthogonal squaring algorithm. The extent of the squaring is determined by the squaring angle.

Learn how to modify the squaring angle

When squaring is performed, additional attributes are stored for the extracted outlines. The attributes that are fit metrics (i.e., goodness of fit) that estimate how well the squared outlines fit around the traced points. The goodness of fit is based on the distances (i.e., the errors) between each point of the traced outline and the corresponding side of the squared outline. The error is calculated perpendicular to the side of the squared boundary, except for the corner points of the squared boundary. In the case of the corner points, the error is the distance between the corner and the corresponding point of the traced boundary. The following is a brief discussion of each fit metric:

• RmsError: calculated by squaring each error and then taking the square root of the average of the squares.
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• MaxErr: the maximum of the absolute value of the errors
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• ForceFit: this is 0 and 1 value. Values of 1 indicates squared outlines that have poor fits, and can be considered of high priority for QA.
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Higher values of each fit metric would indicate poorer fits.

How to Perform Squaring of the Traced Outlines

Perform Squaring Option

1. On the Point Group Tracing and Squaring property page, click the Perform Squaring option to toggle whether squaring is performed.
2. Click the Apply button to commit the changes.