Plotting real-time data in "rolling mode" with the supported graphs is very inefficient.
Every point is recalculated each time the graph is drawn. Shifting the data in a ring-buffer and perform calculation for the new points only would be more efficient.
Something like a "GtkDataboxRT" class to display real-time data would be great.
When the method "Add(x,y)" is called only the new x/y pair has to be calculated according to the actual zoom.
The other points can be shifted in ring-buffer.