BZFlag is a 3D, multiplayer, tank battle zone, capture the flag game that pits players against each other in a networked environment. It runs on Windows 95/98/NT/2000, Linux, MacOS 10.x, Irix, Solaris, and others. An OpenGL accelerator is highly recommended, but it is playable with 3D in software.
The Noble Ape Simulation is a collection of a number of autonomous simulation components including a landscape simulation, biological simulation, weather simulation, sentient creature (Noble Ape) simulation, and a simple intelligent-agent scripting language (ApeScript). Noble Ape also contains a social simulation where the Noble Apes can be tracked in terms of social groups and also over many generations to explain social phenomenon to users looking to study this kind of interaction. It has been in development for more than a fifteen years.
Thousand Parsec is a turn-based space empire building game, as well as a framework for creating a similar group of games, which are often called 4X games (eXplore, eXpand, eXploit, and eXterminate). Some examples of games from which Thousand Parsec draws ideas are Reach for the Stars, Stars!, VGA Planets, Master of Orion, and Galactic Civilizations. Unlike commercial alternatives, it is designed for long games supporting universes as large as your computer can handle. It allows a high degree of player customization, and features a flexible technology system where new technologies may be introduced mid-game.
X-Plane is a flight simulator that reads in the geometric shape of any aircraft and then figures out how that aircraft will fly. It does this via an engineering process called "blade element theory", which involves breaking the aircraft down into many small elements and then finding the forces on each little element many times per second. These forces are then converted into accelerations, which are then integrated to velocities and positions. This gives X-Plane the most realistic flight model available for personal computers.
Visualization Library is C++ middleware for high-performance 2D and 3D graphics applications based on the industry standard OpenGL 1.x-4.x, designed to develop portable applications for the Windows, Linux and Mac OS X operating systems. It supports advanced features like OpenGL Shading Language, Volume Rendering, Isosurface extraction, Frame Buffer Objects, Multiple Render Targets, Vertex and Pixel Buffer Objects, KdTree/AABB frustum culling, a multilingual Unicode-based text engine, advanced texturing, DDS cubemaps, mipmaps, compressed textures, and much more. Visualization Library can be especially useful in 3D/2D scientific visualization, virtual reality, augmented reality, visual simulation, data visualization, presentations, multimedia applications, special effects, and 3D/2D games.
StepSim is a lightweight step-based simulation module written in Python. It can do simple real-time simulations of discrete systems. StepSim supports step-by-step simulation or can run until a break condition occurs. Simulations are made up of containers and converters. A container stores a discrete amount of units of a certain type. A converter draws units from one or more containers and delivers the result to another container. StepSim does not even attempt to do any parallel processing. It processes converters round-robin in a fixed order.