2D to 3D Polyline by Surface Model

Function

This command converts a 2D polyline into a 3D polyline by calculating 3D polyline vertices at all the intersects of the 2D polyline with surface entities (contour polylines, triangulation lines) and by interpolating elevations from these intersections at the original vertices locations. An application for this command is to create breaklines. For example, a ridge breakline could be generated from contour lines by drawing a 2D polyline along the ridge and across the contours. Then this command could grab the contour line elevations along the polyline to make a ridge breakline.

In addition to using entities in the drawing, the 2D polyline can be converted to 3D using a surface model stored in a grid (.grd) file or triangulation (.flt, .tin) file. A grid file is created with the Make Grid File command and a triangulation file is created with the Triangulation File option in Triangulate & Contour.

Prompts

Source of Surface Model (File/<Screen>)? press Enter
Select surface line and polylines.
Select objects: select the surface entities Options include contour polylines, breaklines, triangulation lines, etc.
Reading points ... 1200
Select polylines to convert.
Select objects: pick one or more polylines

Pulldown Menu Location: 3D Data > 2D to 3D Polyline
Keyboard Command: 2dto3dp
Prerequisite: A polyline and surface lines or grid file or triangulation file.
File Names: \lsp\2dto3dp.lsp, \lsp\makegrid.arx