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"Delta3D is a widely used and well-supported open source game and simulation engine. Delta3D is a fully-featured game engine appropriate for a wide variety of uses including training, education, visualization, and entertainment. Delta3D is unique because it offers features specifically suited to the Modeling and Simulation and DoD communities such as High Level Architecture (HLA), After Action Review (AAR), large scale terrain support, and SCORM Learning Management System (LMS) integration."

Organization: MOVES Institute
How to obtain: Download, Free