3D Without Boundaries
VirtualGL redirects 3D commands from a Unix/Linux OpenGL application onto a server-side GPU and converts the rendered 3D images into a video stream with which remote clients can interact to view and control the 3D application in real time.
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.
G3D is a commercial-grade C++ 3D engine. It is used in commercial games, research papers, military simulators, and university courses. G3D supports real-time rendering, off-line rendering like ray tracing, and general purpose computation on GPUs. As of January 16, 2018, SourceForge is again the home of the active repository for G3D.
C++ class library for programming interactive 3D graphics with OpenGL
XNavigator is a Virtual Earth browser and viewer for http://osm-3d.org
XNavigator is the online viewer for the OpenStreetMap Globe at http://osm-3d.org and much more. It is an interactive 3D viewer and integrated client for exploring virtual city and landscape models. A wide range of interaction and navigation possibilities makes it easy to visualize and analyze very detailed virtual urban environments. XNavigator is the first application that supports the Web3DService (W3DS) service interface.
Well just a raytracer in Visual basic 6, thus the name VB6 raytracer. Not because it is easy or logical, but because it is hard. I know this is not the right language to write a raytracer, see it as a stubborn POC that it is still somehow possible.