plot data stream in realtime

[Johannes Deutsch <j_deutsch web de>]

Hi all,

i'm learning gtk since recently and discovered gtkdatabox which seems to
be suited to integrate in my project (a tool to log the step response
of a system). So i'm very new to gtkdatabox and just studying the
examples.

Unfortunately using the examples i can't figure out if the kind of
application i am going to create is actually feasible with gtkdatabox. 

I want to plot a data stream (stepresponse sourced by a fast DAC) in
real time similarly like gnuplot does it in the following video:

	http://www.youtube.com/watch?v=SoF81jc9tDo

Unlike this video shows, the user should be able to scroll back to
regions of previously logged data.

In terms of gtkdatabox i would like to dynamically increase the
interval between the left- and right-limits of the databox while the
size of the zoomed selection should remain constant. This has the
effect, that the scrollbar gradually decrease with remaining time while
permanently aligned at the left corner of the widget (as long as the
user does not scroll).

So far i can't find a function which zooms to a section of the graph. A
function which does just the same what a user can achieve with dragging
the mouse and click inside the selection. Does this function or a
similar function exist? Or is there another way to achieve this?

Also i would like to know how gtkdatabox handles a dynamically
increased datasets!?

I hope some of you experts can help me to answer my questions?

Thanks a lot for your effort and with best regards

Johannes