BRL-CAD package is a powerful Constructive Solid Geometry (CSG) solid modeling system.

The BRL-CAD package is a powerful Constructive Solid Geometry (CSG) solid modeling system with over 20 years development and production use by the U.S. military.

BRL-CAD includes an interactive geometry editor, parallel ray-tracing support for rendering and geometric analysis, path-tracing for realistic image synthesis, network distributed framebuffer support, image-processing and signal-processing tools. The entire package is distributed in source code form.

Now comprising almost a million lines of C code, BRL-CAD has become a powerful constructive solid geometry (CSG) modeling package that has been licensed at over 2,000 sites throughout the world.

It contains a large collection of tools, utilities, and libraries including an interactive geometry editor, raytracing and generic framebuffer libraries, a network-distributed image-processing and signal-processing capability, and a customizable embedded scripting language.

In addition, BRL-CAD simultaneously supports dual interaction methods, one using a command line and one using a graphical user interface (GUI).

Libraries:

The BRL-CAD libraries (designated by the prefix "lib") are designed primarily for the geometric modeler who also wants to tinker with software and, perhaps, design custom tools.

Each library fits into one of three categories: (1) creating and/or editing geometry, (2) raytracing geometry, or (3) image handling. The following is a list of the major BRL-CAD libraries and descriptions of their functions.

- libbu – a basic utility (bu) library containing fundamental computer science types of routines, including manipulating data (e.g., converting from host format data to network format data), parallel processing, parsing parameters, handling variable-length strings, performing error checks, converting units from one format to another, manipulating bit vectors, running parallel-safe versions of input/output (I/O) routines, and maintaining symbol tables.

- libbn – a library of routines to support basic numerical (bn) handling, including 2-D/3-D vector, matrix, and quaternion manipulation; 3-D plotting support; automatic inference of image size (BRL-CAD images have no internal header; image dimensions are intuited from the size of the file); and wavelet decomposition and reconstruction, etc.

- libdm – BRL-CAD's primary graphics display manager (dm) library. It handles opening windows onto the display and displaying geometry in the graphics window, etc.

- libfb – the framebuffer (fb) library, which supports having a window in which the user puts pixel data when raytracing.

- libmultispectral and liboptical – the shader and texturing libraries for the raytracer.

- libpkg – a library that implements a remote procedure call (rpc) mechanism. This library is a predecessor of the modern rpc system. Unlike the typical UNIX rpc service, applications can set up services and handle requests without requiring configuration by a system administrator.

- librt – the library that contains all of the geometry support, including data representations for the primitives, support for raytracing (rt), and binary I/O support for CSG geometric descriptions.

- libz – a public-domain compression library.

- libtcl, libtk, and libitcl – libraries that provide the Tcl/Tk scripting language.

- libpng – a library that provides portable network graphics (png).