MGED

MGED, short for Multi-Device Geometry Editor, is the interactive geometry editor used with BRL-CAD, an open-source solid modeling system developed by the U.S. Department of Defense. MGED provides a command-driven interface for creating, manipulating, and organizing 3D models within BRL-CAD’s native database format.

MGED enables users to build models from a library of constructive solid geometry primitives and to apply boolean operations such as union, intersection, and difference to combine shapes. Common primitives include boxes, spheres, cylinders, cones, toruses, and ellipsoids, among others. In addition to primitive construction, MGED supports transformations (translation, rotation, and scaling), grouping, and hierarchical assembly of parts. Models are stored in BRL-CAD’s database files, typically with a .g extension, and MGED can display geometry in a 3D viewer and export data for use with other BRL-CAD tools or workflows.

The editor has a long history in BRL-CAD, dating back to the 1980s, and has remained a core tool for geometry creation and editing. While MGED remains widely used in BRL-CAD workflows, modern BRL-CAD distributions also provide additional GUI front-ends and utilities that complement or automate parts of the editing process. MGED can be run in interactive mode or invoked to edit existing BRL-CAD databases, making it suitable for both hands-on modeling and scripted workflows.

See also: BRL-CAD, computer-aided design, constructive solid geometry.