LibreDWG

The proprietary format DWG is currently the most used file format in CAD, becoming a de facto standard, without other alternative extended, forcing many users to use this software in a dominant position on the part of the owner company Autodesk.

There did exist the OpenDWG library (later named "Teigha"), to access and manipulate data stored in DWG format, which is developed by reverse engineering by an association of manufacturers of CAD software with the intention of supporting their products. As OpenDWG's license does not allow the usage in free software projects, the FSF created a free alternative to OpenDWG.

GNU LibreDWG is based on the LibDWG library, originally written by Rodrigo Rodrigues da Silva and Felipe Correa da Silva Sanches and licensed as GPLv2 around 2005.{{Cite web|url=http://www.fsf.org/working-together/profiles/felipe-sanches|title = Felipe Sanches — Free Software Foundation — Working together for free software}}

In July 2010 the FSF noted the creation of an alternative to the OpenDWG library as one of 13 "high priority projects".{{ cite web | url=http://www.fsf.org/campaigns/priority-projects/index_html/#opendwgreplacement | author=John Sullivan | title=High Priority Free Software Projects | year=2010 | accessdate=2010-08-03 | language=|archiveurl=https://web.archive.org/web/20100419142732/http://www.fsf.org/campaigns/priority-projects/index_html/#opendwgreplacement|archivedate=2010-04-19}}

In 2009 a license update of LibDWG/LibreDWG to the version 3 of the GNU GPL,[http://sourceforge.net/p/libdwg/code/21/tree//trunk/COPYING?diff=3 trunk/copying] on sourceforge.net/p/libdwg made it impossible for the free software projects LibreCAD and FreeCAD to use LibreDWG legally.{{cite web|url=https://www.phoronix.com/scan.php?page=news_item&px=MTI4Mjc |title=FSF Wastes Away Another "High Priority" Project |first=Michael |last=Larabel |authorlink=Michael Larabel |date=2013-01-24 |publisher=Phoronix |accessdate=2013-08-22 |quote=Both LibreCAD and FreeCAD both want to use LibreDWG and have patches available for supporting the DWG file format library, but can't integrate them. The programs have dependencies on the popular GPLv2 license while the Free Software Foundation will only let LibreDWG be licensed for GPLv3 use, not GPLv2. |url-status=live |archiveurl=https://web.archive.org/web/20161109200145/https://www.phoronix.com/scan.php?page=news_item&px=MTI4Mjc |archivedate=2016-11-09 }}

Many projects voiced their unhappiness about the GPLv3 license selection for LibreDWG, such as FreeCAD, LibreCAD, Assimp, and Blender.{{cite web|url=https://librearts.org/2012/01/whats-up-with-dwg-adoption-in-free-software/ |title=What's up with DWG adoption in free software? |last=Prokoudine |first=Alexandre |date=26 January 2012 |accessdate=12 April 2025 |trans-title=|publisher=librearts.org |quote=[Assimp's Alexander Gessler:] "Personally, I'm extremely unhappy with their [LibreDWG's — LGW] GPL licensing. It prohibits its use in Assimp and for many other applications as well. I don't like dogmatic ideologies, and freeing software by force (as GPL/GNU does) is something I dislike in particular. It's fine for applications, because it doesn't hurt at this point, but, in my opinion, not for libraries that are designed to be used as freely as possible." [Blender's Toni Roosendaal:] "Blender is also still "GPLv2 or later". For the time being we stick to that, moving to GPL 3 has no evident benefits I know of. My advice for LibreDWG: if you make a library, choosing a widely compatible license (MIT, BSD, or LGPL) is a very positive choice." }} Some suggested the selection of a license with a broader license compatibility, for instance the MIT, BSD, or LGPL 2.1.

A request went to the FSF to relicense GNU LibreDWG as GPLv2, which was rejected in 2012.{{cite web|url=https://librearts.org/2012/12/libredwg-drama-the-end-or-the-new-beginning/ |title=LibreDWG drama: the end or the new beginning? |first=Alexandre |last=Prokoudine |date=2012-12-27 |quote=[...]the unfortunate situation with support for DWG files in free CAD software via LibreDWG. We feel, by now it ought to be closed. We have the final answer from FSF. [...] "We are not going to change the license." |accessdate=2025-04-12 |publisher=librearts.org }}

The project was stalled for a few years starting in 2011; this stall occurred for various reasons, including lack of volunteers, licensing issues and programmer motivation.{{cite web|url=https://librearts.org/2012/01/whats-up-with-dwg-adoption-in-free-software/ |title=What's up with DWG adoption in free software? |last=Prokoudine |first=Alexandre |date=26 January 2012 |accessdate=12 April 2025 |trans-title=|publisher=librearts.org |quote=GPLv3 license. It doesn't work for end-user software, because they tend to use 3rd party components under different licenses that impose restrictions. FSF who are sole copyright holders of LibreDWG objected to relicensing. With regards to FreeCAD project and Yorik van Havre, its contributor, Richard Stallman stated:" You should not change the license of your library. Rather, it is best to make it clear to him what the conditions are." [...] Personally, I'm extremely unhappy with their [LibreDWG's — LGW] GPL licensing. It prohibits its use in Assimp and for many other applications as well. I don't like dogmatic ideologies, and freeing software by force (as GPL/GNU does) is something I dislike in particular. It's fine for applications, because it doesn't hurt at this point, but, in my opinion, not for libraries that are designed to be used as freely as possible. }} In September 2013, the original project on which LibreDWG is based, LibDWG, announced that it was reactivating, re-forking its code from LibreDWG.{{cite web |url=http://libdwg.sourceforge.net/en/index.html |title=LibDWG - free access to DWG |last= |first= |date= |accessdate=3 November 2013 |trans-title=}} A GPLv2 licensed alternative is the libdxfrw project, which can read simple DWGs.[http://sourceforge.net/projects/libdxfrw/ libdxfrw] on SourceForge.net

The LibreDWG project has resumed active development, including the addition of more recent .dwg and .dxf formats with version 0.5 in June of 2018.{{cite web|url=https://savannah.gnu.org/forum/forum.php?forum_id=9166 |title=libredwg-0.5 released [alpha]|accessdate=26 September 2020}} The most recent release as of November 2020, version 0.12.5 includes read support for all DWG formats r13+, write support for r2000 DWG and read/write support for all r13+ DXF versions.{{cite web|url=https://savannah.gnu.org/forum/forum.php?forum_id=10114 |title=libredwg-0.12.5 released|accessdate=6 February 2022}} The upcoming 0.13 release will support reading all existing DWG versions.

{{Reflist|30em}}

• {{Official website}}
• [http://libreplanet.org/wiki/LibreDWG Project wiki]

Category:Computer file formats

Category:Computer-aided design