freeglut is intended to be a 100% plug-compatible clone, and is released under the Xfree license. The GLUT (OpenGL Utility Toolkit) is a widely used library for doing window control, keyboard, and mouse input, and other basic functions for OpenGL programs. However, GLUT is not OpenSourced - although it's source code is available under a somewhat ill-defined set of restrictions. Hence, 'freeglut'.
XJRT is an open source Java renderer with a ray tracing backend. Objects can be fed into the renderer either through Java or an XML-based scene description language. Shaders can be written in Java and are instanced using the reflection API. The renderer currently supports a variety of polygons, polygon model formats (3ds, DXF, OBJ, and OFF), spheres and other quartics, cubic patches, heightfields, boxes, torii, blobbies, algebraic surfaces, constructive solid geometry (CSG), and a variety of light sources. Support code is provided for doing tiling, bump mapping, noise based texturing, camera based motion blur, and depth of field.
Seg3D is a volume editing and processing tool that combines a flexible manual segmentation interface with powerful higher-dimensional image processing and segmentation algorithms from the Insight Toolkit. DICOM, VFF, META, NRRD, and many other volume formats are supported. Users can explore and label image volumes using configurable, orthogonal slice view windows and 3D volume rendering.
Mathnetics is an API for creating advanced, interactive, Web-based mathematical applications. It defines various important mathematical objects that are inter-related and on which many numerical calculations can be done. It also features rendering of 3D objects onto an SVG canvas (to do so, it includes certain utilities such as browser sniffing, DOM node selection, and DOM readiness detection), which is quite robust. A few basic 3D objects are given (Line, Sphere, Cube), but the user can define any 3D object desired as per the specification.