The Nebula Device is a free multiplatform game engine currently running under Linux and Windows. It uses OpenGL and/or Direct3D for rendering and Tcl/Tk for scripting. Living C++ objects can be browsed and manipulated at runtime from the builtin console, or remotedly from a minimal terminal based console app. A powerful channel animation system allows any floating point attribute to be animated, and specialized animator classes allow things like realtime bone animation with weighted vertex skin.
RenderDotC (RDC) is a photorealistic rendering toolkit which adheres to the RenderMan(R) standard. Using the Reyes architecture, RDC supports advanced capabilities such as motion blur, depth of field, trim curves, texture/environment/displacement mapping, and programmable shading in the RenderMan Shading Language. The shader compiler included in the toolkit compiles shaders all the way to machine language for the highest possible performance.