updateGL() Help

Hi to everybody
I am trying to develop a 3D plotter using some cubes as marker for my data.

My problem is related to the update of the plot.

Now I've implemented inside my class ( GLWidget ) a method that update my 3D coordinates and in the end calls the updateGL...

this calls the plot, but it does not change at all..

instead if i use the mouse over the display area, to change the orientation of the plot for example, it updates correctly.

Is this all related to the events structure?

I've read about the Qtimer, but i would prefer to control the update of my plot from an external function so my 3d sensor can directly pilot the plot..

Any suggestion?