BRL-CAD Release 7.20.4

BRL-CAD Release 7.20.4

After a few month release hiatus, BRL-CAD 7.20.4 is now available providing several dozen bug fixes and feature enhancements. Our support for NURBS geometry continues to stabilize with improved step-g import support, ray tracing enhancements, better wireframes, and numerous robustness improvements. MGED/Archer continues to approach an alpha release with support added for interactive editing of pipe primitives, improved visualization, new BoT mesh healing capabilities, and more. After many months of effort, our OBJ importer receives a comprehensive overhaul with improved behavior all-around for polygonal mesh OBJ geometry. There is a new exporter to the DOT format used by Graphviz for creating graphs and visualizations of geometry model hierarchies. Efforts to overhaul and enhance BRL-CAD's documentation system were revitalized with effort under way to regenerate and improve our tutorial series.

Many thanks to the many individuals that have contributed to the features and fixes in this release including Carl Moore, Tom Browder, Brandon Hinesley, Zach Easterbrook, Abhijit Nandy, Richare Weiss, Erik Greenwald, Bob Parker, Cliff Yapp, and Sean Morrison. Since release 7.20.2, the following user-visible changes were made:

  • added lighting model visualization options for archer
  • reid command now takes optional -n "incr by" value
  • reid command now returns the last region ID set
  • improved nirt support for non-UNIX-style text files
  • added new relos thickness reassignment command to mged
  • support for loading archer plugins with spaces in name
  • added 'exists' object detection command to mged/archer
  • added archer BoT split/flip/sync surface cleanup panel
  • added new g-dot exporter for hierarchy visualization
  • improved g-vrml successful exporting and reporting
  • added -b BoT dump and -e evaluation option to g-vrml
  • improved obj-g polygonal import
  • fixed mged crash after killing an illuminated object
  • tightened default polygonal mesh export tolerance
  • converted introductory Tcl/Tk presentation to Docbook
  • initial support in archer for editing pipe primitives
  • fixed NURBS raytracing crash due to invalid geometry
  • fixed memory leak when saving BoT geometry
  • improved mged object name globbing support
  • improved bounding box for rpc, epa, ehy, hyp primitives
  • improved handling of degenerate face facetization
  • add support for .png file output in rtwizard
  • improved rtwizard's invocation of rt
  • added object path and keep options to
  • 'keep' command includes sketch when keeping revolve
  • fixed mged 'mater' command inheritance setting bug
  • fixed mged crash removing comb members during edit
  • modified archer startup to not require html documentation files
  • improved mged/archer/bwish run-time path behavior on Windows
  • upgraded libpng to version 1.5.4
  • improved performance of step-g importer
  • fixed browsing mged html help pages on Windows
  • restored mged 'rt' command output to console window
  • fixed infinite loop bug plotting NURBS wireframes
  • added new 'ringworld' procedural geometry generator
  • fixed mged Manual page item in help menu

Please visit the Sourceforge project website to download the latest version:

See the BRL-CAD website at for more information.