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http://brlcad.org - http://brlcad.org
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. |
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Shapeways - http://www.shapeways.com/
Ships physical realizations in a variety of materials of uploaded models. Includes available materials, formats accepted, pricing, tutorials, and support. |
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solidThinking - http://www.solidthinking.com/
Modelling software that supports NURBS, polygonal modeling, and subdivision surfaces, available for Windows and Macintosh. |
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TouchCAD - http://www.touchcad.com/
3D modeling, unfolding and unwrapping program for Macintosh and Windows. |
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ThreeDify - http://www.threedify.com/
Developers of the ActiveSolid 3D solid modeling, CAD prototyping and mark-up sharware application and the underlying BspSolid modelling library. |