Dear ImGui

What it is

Dear ImGui is a small C++ library for drawing user interfaces in immediate mode: you call widget functions like buttons, sliders, and text inputs each frame, and it produces vertex buffers your renderer draws. The core is a handful of source files with no external dependencies, and backends cover common graphics APIs and platforms. Game and engine programmers use it to build editors, profilers, inspectors, and quick tweak panels inside real-time 3D applications, rather than polished end-user interfaces.