I am working on a Qt project, which require visualization of very large data sets (time + value measurements). By very large I mean millions of values.

I need to support scrolling across these values and zoom-in/out operations in the time axis. The ultimate zoom-out should show all the data set sub-sampled to match the window width.

Here are the Qt toolkits I know for drawing the functions:

1. [QWT](http://qwt.sourceforge.net/)
2. [HippoDraw](http://www.slac.stanford.edu/grp/ek/hippodraw/)
3. [KD Chart](http://www.ics.com/products/qt/kdchart/)

I've actually two questions:

1. Do you know any other toolkit for drawing function using Qt?
2. What of the above tools will fit for my purposes better?

If you have any other relative comment / idea regarding my problem, feel free to share.

Thanks :)