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The thing is that 20,000 points is more points than anyone can
reasonably perceive on the screen to get any useful information.
You are on the right track to consider clustering.<br>
<br>
My application (tracking 70 boats across the Pacific) gives me a raw
data set of about 15,000 points each with lat, lon, time, and boat
id. That's a lot of data to process and to upload.<br>
<br>
What I am doing instead is pre-thinning the data using the
Douglas-Peuker algorithm on the server side, which nicely reduces
the data to any level of detail you care to specify. I got about a
90% reduction in point count with no real loss of information on
tracks.<br>
<br>
If your data is not lines, but discrete points, then I am less
versed. Yeah, clustering sounds good. You may also want to use the
BBOX strategy to only fetch the points that are relevant to your
map. <br>
<br>
I can post the douglas-peuker code somewhere if that would be of
value.<br>
<br>
Michael<br>
<br>
On 9/6/2011 6:15 AM, Tito, Joseph wrote:
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<p class="MsoNormal">I’m trying to expand one of my current
application to handle larger amounts of data. Right now the
application comfortably handles 2000-3000 points at a time,
but I'd like to expand its capabilities to handle at LEAST
20,000 points. More would be nice, but the minimum requirement
is 20,000. Displaying these 20,000 points as X number of
‘clusters’ is totally acceptable, as long as it gives a good
visual representation of the full data set.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">One thing I need to take into consideration
is that I have multiple data types represented as their own
layers, and each user has the ability to turn on/off layers
based on their personal preferences. <br>
<br>
My question to everyone is, how have others solved this
problem? I have a couple server side ideas to "pre-cluster"
data in mind, but I want to see how others have tackled this
problem before I attack it. If anyone has links to other
relevant posts or websites, please share!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thank you<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Joe Tito<o:p></o:p></p>
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