This command extends 3D polylines to a surface. The 3D polyline
is extended from the selected end of the polyline using the slope
of the polyline end segment until this vector intersects the
surface. The surface is defined by a 3D grid or triangulated
surface model which can be selected from a .grd, .flt or .tin
file.
Select Surface File Pick a triangulation or grid
surface
Pick polyline to extend: pick a 3D polyline
Pick polyline to extend (Enter to end): press
Enter
Pulldown Menu Location: 3D Data
Keyboard Command: surf_extend
Prerequisite: 3D Polylines and a surface model file