Crystal Space

A software development kit for realtime 3D games or other simulation-like visualization.
Low-level Graphics Library written in C++ based on OpenGL, with bindings for Python, Perl, and Java.
Supports meshes, static lighting, vertex and fragment shaders, texture mapping, Level-of-Detail, collision detection, physics, sound, and scripting and triggers. Has a foliage generator. Supports an object registry, event queue, virtual clock, and a variety of input managers. Supports frame-based animation and skeletal animation, as well as "sockets" which allows objects to be attached (such as a cup in a hand).

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