Ca3DE is an all-purpose, modern 3D graphics engine.
It can be used to create a variety of 3D applications, including games, simulations, and training and architectural software.
Its main features include high-quality, real-time 3D graphics, cross-platform and cross-compiler portability, multi-player network support, physically correct lighting (radiosity based), dynamic per-pixel lighting and shadows, 3D sound effects, skeleton based model rendering, and easy extensibility by MODs.

License: unknown (Free demo and development kit.)

Additional System Requirements:
FMOD
Requires at least a GeForce3 or ATI Radeon 8500.