MBDyn_sim_suite is a collection of free pre&post-processing tools and simulation models for the open-source multi-body analysis software MBDyn forming a general purpose simulation environment for structural dynamics with an emphasis on wind turbines.
MyWorld is an open virtual reality and game engine. It is written and usable in C/C++. It has own abstract layers for Graphics and Physics. Actually we use Irrlicht for 3D-Rendering and GUI, and ODE for Physics. It is smart, powerful and easy to extend.