Click anywhere inside the drawing canvas above to plot a point.
Plot a point, enter the respective parameters and click any one of the "Draw
Circle", "Fill Circle", "Draw Ellipse", "Fill Ellipse", "Draw Arc", "Fill Arc",
"Draw Rectangle" or "Fill Rectangle" buttons on right side.
Check the output with various parameters like pen width and color.
"Clear Canvas" button is to clear the canvas completely.
If you find some bug/defect in the demo application, please report the bug with
the "Point" and Parameters.