Plot graph is interfaced with abstract
Display class.
There is currently single implementation available,
DisplayOpenGL.
Display is updated via OnTimer event if new data arrived or canvas has to be repainted.
DisplayOpenGL uses Canvas of TPanel as drawing surface. Since TPanel has no OnPaint event additional TPaintBox with exact size of TPanel is used to check if repainting is needed.
DisplayOpenGL uses floating point coordinated internally.
