An Open Source CSG solid modeling system with ray tracing support for rendering and geometric analysis, network distributed framebuffer support, image-processing and signal-processing tools.

Developers of the ActiveSolid 3D solid modeling, CAD prototyping and mark-up sharware application and the underlying BspSolid modelling library.

A free 3D solid modelling software offering fast hidden line removal, topological functions, 3D geometric constructions, IGES support, shading, printing, hatches, and line constructions.

Keyboard driven modelling software that supports complex curved surfaces.

Modelling software that supports NURBS, polygonal modeling, and subdivision surfaces, available for Windows and Macintosh.

3D modeling, unfolding and unwrapping program for Macintosh and Windows.