BRL-CAD is a constructive solid geometry (CSG) solid modeling computer-aided design (CAD) system. It includes an interactive geometry editor, ray tracing support for graphics rendering and geometric analysis, computer network distributed framebuffer support, scripting, image-processing and signal-processing tools. Developed by U.S. Army Research Laboratory
License: Open Source
Autodesk Inventor is a powerful commercial CAD software known for its advanced simulation and assembly modeling capabilities, making it ideal for professional engineering design. In contrast, BRL-CAD is an open-source alternative that excels in geometry editing and is widely used in academic settings, but it lacks some of the advanced features and support found in commercial software.