If you've ever programmed or know SDL, Allegro libraries, or any kind of framework, you may have noticed all the save time by yourself to implement certain system calls or the language you want to use.
raylib is a small open source library under the license zlib/libpng in C very interesting with simple examples so you can create multiplatform games or multimedia applications. Also supports Android, HTML5 and of course Raspberry Pi.
Uses C# PascalCase/camelCase notation
Hardware accelerated with OpenGL (1.1, 3.3+ or ES2)
Unique OpenGL abstraction layer [rlgl]
Powerful fonts module with SpriteFonts support
Multiple textures support, including DDS and mipmaps generation
Basic 3d support for Geometrics, Models, Heightmaps and Billboards
Powerful math module for Vector and Matrix operations [raymath]
Audio loading and playing with streaming support (WAV and OGG)
The current version is 1.2.2 and you have an installer for Windows or you can easily compile with instructions that you can follow on Github.
Source Code: Github > raylib