'''[http://brlcad.org/%|%BRL-CAD]''', originally by [https://en.wikipedia.org/wiki/Mike_Muuss%|%Mike Muuss], is a powerful cross-platform [open source%|%open-source] [CAD]/solid-modeling system that featues interactive geometry editing, high-performance ray-tracing for rendering and geometric analysis, image and signal-processing tools, a system performance analysis benchmark suite, libraries for robust geometric representation, with more than 20 years of active development. [http://brlcad.org/gallery/var/resizes/screenshots/MGED.jpg] ** News ** 2013-12-16: BRL-CAD selected as a participant in [http://www.google-melange.com/gci/homepage/google/gci2013%|%Google Code-In 2013] ** Description ** To provide for the construction of realistic models of complex objects from a ralttively small set of "primitive shapes", BRL-CAD employs the basic Boolean operations of union, subtraction, and intersection, and assigns reals-world material attributes. The '''Multi-Device Geometry Editor''', comprised of over 100K lines of application logic in [Tcl]/[Tk]/[incr Tcl%|%Itcl]/[incr Tk%|%Itk]/[Iwidgets], is the heart of BRL-CAD, and its [GUI] is the primary user interface to the system. It calls into Tcl from [C] for nearly all tasks, including [Event Processing%|%event handling], [logging], [I/O], and other operations. Both the large red window and the smaller rendering window have graphics contexts implemented via [Tk C API], with the larger one providing a custom interactive [3D Graphics%|%3D] environment using Tk [Pixmap] and the smaller displaying an asynchronous incrementally rendered (ray traced) 2D image using Tk_PhotoImageBlock. There’s also dozens of complex/custom dialogs, windows, and other elements not shown. [http://wiki.tcl.tk/17805#pagetocad1fdaa5%|%1]. ** History ** Since 1979, the U.S. Army Research Laboratory has been developing and distributing the 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, a network-distributed image-processing and saignal-processing capability, and an '''embedded scripting language'''. ** References ** 1: [http://code.activestate.com/lists/tcl-mac/1918/%|%MACTCL: Aqua MGED on Mac OS X], Christopher Sean Morrison, 2015-06-19 <> Application