C3D.lsp.zip – LISP program converting LWPolylines to 3DPolylines while preserving OD.
AutoCAD Map/Civil 3D, 2010-2022.
Author: Juan Villarreal/Joe Burke/V. Azarko.
Call command: LWto3DPoly.
Warning: The command does not allow you to select objects.
The command converts all LWPolylines to 3DPolylines while preserving OD and XData and all other graphical properties.
Warning: The command will save only one OD per object and may not save the Linetype scale.
See also, LWto3DPoly.lsp - the best version of the converter.