1. LlglLow Level Graphics Library (LLGL) is a thin abstraction layer for the modern graphics APIs OpenGL, Direct3D, Vulkan, and Metal
3. MentalGLSingle header OpenGL utility library in the public domain
4. GaussianLibBasic linear algebra C++ library for 2D and 3D applications
5. PicoRendererLow-Level, 8-bit Colored, 3D Software Renderer written in C99