[uDraw(Graph)-Users] How to use API updates

[Mattias Werner]

Hello,

Pieter Bellens wrote:
> Initially, UDG can keep up with the external program that generates the
> nodes and edges. When the graph reaches a size of 100 nodes, 300 edges
> or so, it slows down to the point of being useless. Hence, the problem
> doesn t seem to be the large amount of smallish updates (only one node,
> or several edges), because initially, UDG can cope with those. Rather, i
> would think that the problem is that UDG can t cope with large-size
> graphs, no matter the size of the updates. Since UDG only accepts one
> update at a time from the pipe, the size of the update is irrelevant,
> wouldn t you say? I mean, if UDG displays a large graph at the moment,
> and it responds very slowly to a very small update (my present
> situation), i would expect it to be even slower, when sending over a
> large update (your suggestion).  

the larger the graph, the more difficult it is to insert the update into
the graph and to recalculate the incremental layout, that's true. I could
try to find out, what slows down uDraw(Graph) if you send me the API
log-file. You can create it by calling:
   uDrawGraph -log logfile.txt

If uDraw(Graph) takes time S for a small update and time N*S for N small
updates, the time for a large update containing all the N updates will be
much smaller than N*S, because our algorithms are optimized for inserting
large updates at once. If you send only small updates nothing can be
optimized.

> If you can assure me that the lack of responsiveness from UDG will
> disappear when using bigger updates, i m inclined to believe you, of
> course. But i would like to be absolutely sure before spending another
> week coding the changes, and finding out the opposite. I just don t see
> the reason why bigger updates would remove the problem.

I can't assure you anything but if you send me the above logfile, I can
have a look at it and maybe find out what the problem is.

Regards,
Mattias Werner
uDraw(Graph) project

-- 
		Dipl. Inform. Mattias Werner
		Bremen Institute of Safe and Secure Systems (BISS)
		Bremen University
		E-Mail: mawe at informatik.Uni-Bremen.DE
		WWW:	http://www.informatik.uni-bremen.de/~mawe/