Generate waveformed signal and play it. Interactive GUI with movable datapoints.
It is part of DJ toolbox project: http://dj-toolbox.9f.com/ Author: http://simulations.narod.ru/ It define form of one period of signal. It is possible to move points with mouse.
Nearest, linear, spline interpolations method are used. It is possible to make continius signal.
Sound can be played or saved to wav file. Window is resizable.
See wikipedia about waveform: http://en.wikipedia.org/wiki/Waveform