K-3D is a 3D modeling, animation, and rendering system for GNU/Linux & Win32. Features include creation and editing of geometry in multiple realtime OpenGL solid, shaded, and texture-mapped views; unlimited undos and redos; complete extensibility at runtime through third-party plugins; animated procedural geometric effects; all parameters animatable through a consistent control-spline based interface; rendering pipeline to Renderman Interface compliant rendering engines; optimization for use with the Aqsis rendering engine, which features solid modelling, true displacement, and user programmable shaders; and support for background and batch rendering.
VariCAD is a 3D/2D CAD system for mechanical engineering. In addition to standard tools for 3D modeling and 2D drafting, the CAD system provides tools for sheet metal unbending and crash tests, libraries of standard mechanical parts (ANSI, DIN) and symbols, mechanical part calculations, and tools for working with bills of materials (BOMs) and title blocks. VariCAD supports STEP, STL, IGES, DWG, and DXF file formats.
The Interreality project is a collection of Open Source, Free Software projects based on the Virtual Object System (VOS) platform. The goal is to develop a free and open platform for multi-user 3D virtual reality games, applications, and interactive, collaborative 3D virtual spaces. VOS is a powerful and generic network object framework designed to support a variety of high-performance applications. It is the basis for Ter'Angreal, a general-purpose browser application for entering and participating in 3D worlds.
Moonlight|3D is a modeling and animation tool for three-dimensional art. It currently supports mesh-based modeling. It's a redesign of Moonlight Atelier, formed after Moonlight Atelier/Creator died in 1999/2000. Rendering is done through pluggable backends. It currently supports Sunflow, with support for RenderMan and others in planning.
Ayam is a free 3D modelling environment for the RenderMan interface. It features good RIB export, CSG (all RenderMan primitives supported), and NURBS modelling. Features instancing, arbitrary number of modeling views, object clipboard, independent property clipboard, n-level undo, console, and Tree-View with Drag-and-Drop support.
Terraform allows you to create fractal terrain (also called a height field) and transform it using a number of algorithms. It is meant to be a tool for those who want to generate digital terrain models for use in raytracing or other simulations. Terraform features different views and colormaps and has a preview mode which features interactive real-time rotation of the terrain object. Terraform is written for the GNOME desktop environment.
SharpConstruct is an OpenGL graphics application that supports real-time sculpting of polygon meshes. The process is similar to painting on a canvas in a traditional 2D image program, but with an added dimension. Depth is simply brushed onto the model, offering an easy way to create highly detailed meshes.