A pretty big list of C++ GUI libraries - r/cpp / C++ UI Libraries

see also

• C++ Game Engine Libs
  • raylib - a simple and easy-to-use library to enjoy videogames programming.
    • Making a 3D modeler in C in a week - show some limitations of Raylib

Image manipulation

• libVIPS - Compared to similar libraries, libvips runs quickly and uses little memory.
• dlib - a modern C++ toolkit containing machine learning algorithms and tools
• sfml - a simple interface to the various components of your PC

2D vector graphics library

• cairo - a 2D graphics library with support for multiple output devices

• Anti-Grain Geometry Library (AGG) / Home - abandonned ?

• ThorVG