KWWidgets is a free, C++ cross-platform and open-license GUI Toolkit based on Tcl/Tk. Over a hundred C++ classes have been developed and used by Kitware, Inc. to create open-source and commercial end-user applications like ParaView or VolView, for more than 7 years. Is is also used by the National Alliance for Medical Image Computing for the 3D Slicer project.
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