(Libgdx is composed of such primary class libraries as audio, files, graphics, math, physics, scenes, and utils. They correspond to audio operations in Libgdx, file reading, 2D/3D rendering, Libgdx drawing related operations, Box2D packaging, 2D/3D game components (3D parts now have no components), and Libgdx built-in tool classes. This document includes the following annexes:)