[Paraview] Current state of LiveData

[Fabian Wein]

Hi David,

> 1) You have to recognize when data is available and complete, and you
> need some sort of atomicity guarantee. Ie, you don't want a reader
> trying to read a half written file, and you don't want the some
> process modifying the file while the reader is halfway through reading
> it.
> 
> 2) The reader has to be marked Modified() when there is something new
> to read. Otherwise the downstream pipeline won't know that what it
> last produced isn't up-to-date, and won't call RequestData() on it.
> 
> 3) The downstream end (mapper/renderwindow/view/writer or whatever)
> has to be told to Update()/Render() so that the reader's new results
> show up.

Thanks for the information!
I'm working along this guideline, there are several problems I'm fighting
with but this seems exactly to be the information I needed.

Fabian