Autodesk CIVIL3D - CIVILDESIGNCOMP 2007 SLM CD Tutorials Manual page 241

4 In the Alignment Properties dialog box, click the Masking tab.
5 On the Masking tab, click
6 In the drawing, click the end point on the northwest curb return to specify
the start point of the masked region.
7 Click the end point on the northeast curb return to specify the end point
of the masked region.
Exercise 3: Applying a Mask to an Alignment | 229
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