> Since 1979, the U.S. Army Research Laboratory (ARL) has been developing and distributing the U.S. Army Ballistic Research Laboratory - Computer-Aided Design (BRL-CAD) constructive solid geometry (CSG) modeling package for a wide range of military and industrial applications. The package includes a large collection of tools and utilities including an interactive geometry editor, raytracing and generic framebuffer libraries, network-distributed image-processing/signal-processing capabilities, and an embedded scripting language.
From one of their tutorials (https://brlcad.org/w/images/9/9a/Principles_of_Effective_Mod...):
> Since 1979, the U.S. Army Research Laboratory (ARL) has been developing and distributing the U.S. Army Ballistic Research Laboratory - Computer-Aided Design (BRL-CAD) constructive solid geometry (CSG) modeling package for a wide range of military and industrial applications. The package includes a large collection of tools and utilities including an interactive geometry editor, raytracing and generic framebuffer libraries, network-distributed image-processing/signal-processing capabilities, and an embedded scripting language.