Gdk

GDK, short for GIMP Drawing Kit, is a low-level cross-platform library that forms part of the GTK project. It provides the windowing and input primitives that GTK applications rely on, abstracting away platform differences and offering a common API for displays, windows, events, and drawing surfaces.

GDK sits between the GTK toolkit and the underlying window system. It handles the creation and management of top-level windows, event handling (keyboard, pointer, touch), accelerators, drag-and-drop, and clipboard access. It also exposes backends for different platforms, such as X11 and Wayland on Unix-like systems and native backends on other platforms, enabling GTK applications to run across environments.

Typical GDK concepts include GdkDisplay, GdkWindow, GdkScreen, GdkEvent, and GdkDevice. The library provides event dispatch, coordinate mapping, and input method support, and it serves as the conduit through which GTK draws widgets onto windows. To render, GTK often uses Cairo via GDK drawing surfaces, with evolving support for newer rendering backends in GTK 4.

GDK is maintained as part of the GNOME project and is released under the LGPL. It is primarily used by GTK applications to interact with the windowing system, but it can also be used by other software that needs low-level windowing and input facilities across platforms.

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