In addition to bringing up a GUI, the OpenSCAD executable creates snapshots of rendered .scad files.
Here is a sample invocation:
$ /cygdrive/c/opt/openscad/openscad-2015.03-2/openscad -o out.png --camera=0,0,0,0,0,0,350 space-invaders-scenes-CUSTOMIZER.scad
--camera
the last parameter is the distance away from the object
Date Created: 2016-09-27 22:02:58 -0500 (Tue, 27 Sep 2016)