fltk
C++ GUI Toolkit for the X Window System, OpenGL, and WIN32
The Fast Light Tool Kit ("FLTK", pronounced "fulltick") is a C++ graphical user interface toolkit for the X Window System, OpenGL, and Microsoft Windows NT 4.0, 95, or 98. The installation of this package requires a 3D library such as Mesa.
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The following distributions are not officially supported. Use these packages at your own risk.