Hi Sherman,

I don't have any easy off the shelf answers, but it does sound like
some kind of paging mechanism would be appropriate.  I wonder if you
create a subgraph from Switch or similiar node and have its subgraphs
turned on and off depending upon the time that they are available for.
The children then could be ProxyNode's or PagedLOD's that
automatically page in the data once the time comes into the
appropriate range.

Robert.

On 2/18/07, sherman wilcox <[EMAIL PROTECTED]> wrote:
My question is this: what's the best way to update dynamic data within the
OSG framework?

In this particular instance, I have data that is organized in clumps all
tied to a specific moment in time. Aircraft position data is a good
illustration. For example, I could generate a database that contains
aircraft position information that spans hours if not days. This data is
often organized such that I can display the position of all aircraft in my
database for a specific time. For example, suppose I choose to display the
positions of all aircraft in my database @ 12:00 yesterday. After I retrieve
all that data and have it in memory, I could end up with thousands of
elements. If I increment the time to say 12:30, I get a slightly different
dataset, again with thousands of elements. If I increment the time rapid
enough, I can animate the paths of these aircraft on-screen. Problem is,
there are thousands upon thousands of elements that could be displayed
on-screen at any given time. I'm not so concerned with how to visualize this
data or even the performance of the rendering portion of the problem. In my
mind, rendering the data is the easy part. The more difficult portion of
this problem for me is how to update the nodes dynamically without dropping
frames.

I've worked with OSG long enough that I know of a couple of different ways
to tackle such a problem, but none seem elegant. For that matter, I suspect
I'd incur a performance penalty every time I try to update the nodes due to
the shear number of elements.

One method I've considered is to retrieve the new list of elements on a
background thread and update the node in question that holds all this data
to display after sync. But I'm not so sure this is the best way.

Does anyone have any suggestions of what's the proper way to go about
something like this? An OSG example or perhaps a bit of advice from someone
with more experience than myself would be helpful.
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