libTISCH is a framework for easy development of multi-touch applications. It contains tools for video processing, calibration, gesture recognition and, most importantly, a GUI toolkit with widgets that utilize the multi-touch gestures detected by the lower layers. It runs on Linux, Mac OS X, and Windows.
Minimal OpenGL Utility Library (MOGUL) is a library similar to GLUT, only with fewer features. It lets you write window-system-independent OpenGL programs with even fewer lines of code than GLUT. It currently supports X11 and Win32. Examples are included in the distribution. It is intended to be easy to learn and simple to use.
Faith is a cross-platform C++ graphical application toolkit. It runs natively on Linux/Unix (Xlib) and Windows. It has an API strongly inspired by Qt's and has many features that are expected from a modern toolkit, including a variety of common "widgets", an aesthetically pleasing appearance, and the many critical non-portable components such as anti-aliasing and sockets.
PageLayout is a layout lanager for Java Swing/AWT that encapsulates, in a single library, the functionality of many other layout managers. It allows you to lay out components in appropriately aligned rows, columns, and grids. The elements of rows, columns, and grids may themselves be rows, columns, and grids of components. As a result, relatively complex layouts can be managed with code that is compact and conceptually quite straightforward to understand and, therefore, maintain.
reacTIVision is a computer vision framework for the fast and robust tracking of fiducial markers attached to physical objects, as well as for multi-touch finger tracking. It was mainly designed as a toolkit for the rapid development of table-based tangible user interfaces and interactive multi-touch surfaces such as the reacTable. Client application examples are available for various programming environments such as C++, Java, C#, Processing, PureData, Max/MSP, and Quartz Composer.
The OpenInput library is intended as a free (libre), easy-to-use, cross-platform input handler library. The goal is to provide an SDL-like interface to input devices such as keyboards, mice, and joysticks while keeping the dependencies for the library at a bare minimum and making it simple to integrate in existing projects. All functions and data structures are intuitive and fully documented. The library has support for both event-based input handling and unbuffered input.
Clean Programming Language is a general purpose, state-of-the-art, pure and lazy functional programming language designed for making real-world applications. Its unique typing system makes it possible to incorporate destructive updates of arbitrary data structures (including arrays) in a pure functional language and to make direct interfaces to the outside imperative world.