asc-nmg — ascii-to-NMG converter


asc-nmg ascii_file nmg.g


asc-nmg converts the specified ascii_file (not a .asc geometry database) to a binary BRL-CAD nmg.g geometry database file containing NMG objects. The ascii_file is expected to contain lines of the following forms:

To start a new outer loop for a face:


To start a new "hole" loop in the current face:

l hole

To indicate a vertex in the current loop:

v# x y z

where # is the vertex number and x, y, and z are the coordinates of that vertex.

To extrude a face:

e x y z

where x, y, and z compose the extrusion vector for the face.

If an extrusion vector is specified, then the first face in the NMG objects list of faces will be extruded. This is intended for cases where only one face is described and then extruded to form a solid. Supplying an extrusion vector when more than one face is described may produce erroneous results. A solid may be built by extruding a face or by building enough faces to produce a closed shell. Each execution of asc-nmg will produce a single NMG object.


If the file ascii_file contains the following:

e -1 0 0
v0 1 -1 -1
v1 1 1 -1
v2 1 1 0
v3 1 0 0
v4 1 0 1
v5 1 -1 1

the command:

$ asc-nmg ascii_file sample.g

will produce an 'L'-shaped NMG solid to the sample.g database file.


Error messages are intended to be self-explanatory.




This software is Copyright (c) 1994-2016 by the United States Government as represented by U.S. Army Research Laboratory.


Reports of bugs or problems should be submitted via electronic mail to <>.