Open Source Solid Modeling CAD
BRL-CAD is a powerful cross-platform constructive solid geometry solid modeling system that includes an interactive geometry editor, ray-tracing for rendering & geometric analyses, network distributed framebuffer support, image & signal-processing tools.
AfA-Scumm is the 2D adventure engine powering AmberfishArts, a community for enthusiasts of classic adventure games as well as a hub for high-quality fan projects. Coded in C++, AfA-Scumm is both very portable and feature rich.
A fast, unobtrusive and modern cross-platform GUI toolkit. Agar fully exploits hardware acceleration where available, but also supports simple frame-buffer interfaces. Agar is stand-alone and easily portable to new platforms and graphics systems.
The UnifiedSessionsManager recoded based on Python
Rpg2Cpp (Rpg++) is a compiler that translates RPG-III and RPG/400 sources from IBM-midrange systems (iSeries, AS/400) to native C++ code. C++ class-libraries resembling the RPG-III datatypes are included as well as a tiny CL-runtime-system.