# You want this going through so that you can cut a hole through the object. # This is the basic hollowed-out box shape: $granularity = 1500 # this is the total number of segments $t_max = 10 * PI # 2*PI per revolution so 5 revolutions # Generates a 3D model of a spiral via BRL-CAD. This avoids considerable operating system and process initialization overhead, allowing the script to run orders of magnitude faster than if the segments were created one at a time.

It builds up a list of commands for one segment, then groups them together in batches of 100 before running MGED.

This script takes advantage of the fact that it is considerably more efficient to batch multiple MGED commands together instead of re-invoking MGED multiple times. First in Ruby written by, Dwayne Hans, 2016. The '-c' option tells MGED to run in classic console mode without a GUI, which is perfect for scripting from most any language including Perl. The shapes are then combined together into a proper region, and a resulting render is shown.īRL-CAD's solid modeling editor, MGED, will run most commands provided after the name of the geometry database on the command line. The script creates boxes (RPPs) with holes cut out of them as an underlying shape pattern, then replicates that shape around in an outward spiraling pattern.

Included below is an example Perl script that uses BRL-CAD tools to procedurally create and render a spiral of boxes. Spiraling boxes, modeled with a Perl script and rendered in BRL-CAD

Brl cad scripting