A C++ based core library for GUIs. Uses OpenGL as drawing library and SDL/Glut as windowing toolkit. [Open source, LGPL]

API toolkit for developing GUIs with LCD driver library graphics and graphical display controller drivers. Graphic LCD module application using advanced features like proportional writing, icons, lists and scroll boxes, line drawing.

A free bubble or balloon help X Widget.

An open source project aimed at making UI coding easier. The C++ library introduces rules-based UI coding, reflections and several other mechanisms to speed up UI coding.

A GUI framework for use in interactive OpenGL applications. The main goal is to provide very easy and fast way to develop portable interactive interfaces, using object-oriented approach. [Open source, BSD License]

Provide Unix and Java GUI builder tools such as JClass, JProbe, UIM/X, db-UIM/X, XRT and Platinum.

A platform independent graphical user interface library developed specifically for games.

A rich thin client framework for building software applications that combine the usability and speed of desktop software GUI with the centralized administration and universal accessibility of Web apps.