Editing Solids and Surfaces - Autodesk AutoCAD 2013 Practical 3D Drafting and Design - page 232

• Distance : Instead of specifying a point, this option prompts fora distance
and to which side the offset is made.
• Corner : When offset is outside the edge, this option controls if the result-
ing corners are sharp or rounded. In this case, the radius is equal to the
distance.
The SURFEXTRACTCURVE command
The SURFEXTRACTCURVE command (no alias), which is new in Version 2013, allows
us to obtain curves (isolines) from surfaces or solids. The new objects can be lines,
arcs, polylines, or splines. The command starts by displaying the default value of the
Chain option and prompts for the selection of one surface, solid, or face:
Command: SURFEXTRACTCURVE
Chain = No
Select a surface, solid, or face: Selection
Specifying a point over the surface creates a curve. The prompt is repeated until the
command is ended:
Extracting isoline curve in U direction
Select point on surface or [Chain/Direction/
Spline points]: Point
Extracting isoline curve in U direction
Select point on surface or [Chain/Direction/
Spline points]: Enter