Re: Gtk_Tree_View, drawing speed

[Arne Pagel <arne pagelnet de>]

Hello Vlad,

an update frequency about 400Hz is absolutely not necessary,
and I agree that no human could follow that.

My Target is 100ms.
This gives an acceptable picture, even if I use later progress bars for visualization.
You will defenitliy notice a difference between 100ms and 33ms.
If I use numerical values, and even if you can not read the last number, you have some Information, you see 
that there is a fast change.
The other thing is that I have build in the possibilitiy for a Binary Display where I currently use a Toggle 
Button. In the Future my plan
is to change to a LED like view, where you also can notice very short events.

Anyway, to achieve 100ms, the maximum possible update Frequency should by higher.

At the moment I have just on Object with 12 Elements in my TreeView,
but later I want to have more Objects with more Elements in the view, with the current approach I would 
already touch the boarder.

Also I want to reduce the CPU load for this process.
Well, an WebVideo with 30 fps and an much more changing pixels requires less CPU load.

A feature I plan is also to give the possibility to log Data to a file, but if the visualization causes high 
CPU load,
and therewith high jitter, the quility of this log will be bad

One other thing is, I already know that a fast Display is possible, like if I just use 1 Element Objects.
Optically there is not so much difference, so what is causing the delay.

Did you ever see the Mega-Tunix Project?
http://sourceforge.net/projects/megatunix/
They mad some very cool gauges which I used a few years ago, with also more then 10Hz,
and acceptable CPU Load, even on a weak Industrial PC

regards
  Arne



Am 27.09.2012 13:27, schrieb Vlad Volodin:
> Hello Arne,
>
> Is it really necessary to refresh updates 400 times per second? To be
> honest, me as a human will not notice all these changes. What do you
> think about doing updates once or two times per second? (like all task
> managers do) E.g. you can collect all values that come from the
> hardware and display the average value only.
>
> Kind regards,
> Vlad