GZDoom (open-source project; maintained by Christoph Oelckers)

GZDoom is an open-source source port of id Software's Doom engine that focuses on modern rendering, extended scripting, and advanced modding support. Originally part of the ZDoom family of source ports (which began as ZDoom by Randy Heit and others), GZDoom provides a feature-rich, OpenGL-accelerated engine that preserves compatibility with classic Doom mods while adding modern graphical effects, translatable UI, and high-level scripting. It is community-driven and primarily maintained by Christoph Oelckers (GitHub: coelckers).

The project is widely used by the Doom modding community to create and play advanced mods, total conversions, and enhanced levels that leverage features such as dynamic lights, shaders, particle systems, and the ZScript scripting language. Releases are published for Windows, macOS, and Linux, and the source code is hosted and developed on GitHub. The project is distributed under the GNU General Public License (GPL) and has an active user and developer community...