[OpenLayers-Dev] Making BBOX strategy smarter - part2

Ivan Grcic ivan.grcic at geofoto.hr
Thu Nov 13 06:32:03 EST 2008

Hi, i just saw that by default bbox has a ratio parameter:2 Creating
bbox strategy with lower value did a lot of improvement for me, since
it fetches much less data (filtering it)
The improvement is off course noticable more on larger scales (zoomed out)

new OpenLayers.Strategy.BBOX({ratio:1.4}

Regards, Ivan

On Thu, Nov 13, 2008 at 12:04 AM, Christopher Schmidt
<crschmidt at metacarta.com> wrote:
> On Wed, Nov 12, 2008 at 11:20:00PM +0100, Ivan Grcic wrote:
>> This post continues on previous discussion opened under name "bbox
>> strategy and zooming"
>> OK, I made a little mess here :) Im pretty new with this, so I still
>> dont know really well how things function.
>> > Tim says
>> > Keep in mind that the cluster strategy doesn't know anything about bbox, and vice-versa.
>> So what  bbox does, is fetching the data, and cluster is then, well
>> clustering that data? (without getting any new data, cuz thats bbox'es
>> work)
>> So on layer pan/zoom, first bbox is activated to fetch, and then
>> cluster to process. Did i get it right?
>> Well knowing that, then thers not so much to say about Cluster
>> strategy. Its allready doing its job pretty well.
>> Its only about making bbox more efficient, cuz of reasons that
>> Tim/Christopher said:
>> Tim said:
>> > I want to have maxfeatures, and more aggressive invalidation because of it.
>> Christopher said (thats my case btw)
>> > Someone else might have a specific need to make the strategy more
>> > aggressive because the server returns more detailed data based on the
>> > extent of the request (I don't know, just making things up here).
> These are actually reversed -- I'm Tim above, and Tim is Me.
> Regards,
> --
> Christopher Schmidt
> MetaCarta

Ivan Grcic

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