[Paraview] Current state of LiveData

[David E DeMarle]

VTK is demand driven and lazily evaluated. This means three things
have to happen for in-situ vis to work.

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.

David E DeMarle
Kitware, Inc.
R&D Engineer
28 Corporate Drive
Clifton Park, NY 12065-8662
Phone: 518-371-3971 x109



On Wed, Oct 7, 2009 at 11:43 AM, Fabian Wein
<fabian.wein at am.uni-erlangen.de> wrote:
> David E DeMarle wrote:
>> This topic has been coming up more and more frequently.
>>
>> This link is to the most recent discussion about it:
>> http://markmail.org/message/734wfelphy3uepjr
>>
>> (search markmail's paraview archive for in-situ, realtime, and/or live data)
>
> Thanks for your reply. I'm still fighting ...
>
> As fas as I have seen so far there is no way to trigger RequestData()
> from the C++ plugin ?!
>
> As it is urgent, I liked Pat's idea
>
> this->Implementation->PythonManager.pythonShellDialog()->runScript("update_visualization.py");
>
>
> http://markmail.org/message/734wfelphy3uepjr#query:+page:1+mid:734wfelphy3uepjr+state:results
>
> It's just the update_visualization.py missing :(
>
> I appreciate more input :)
>
> Fabian
>
>
>