[OpenLayers-Users] IE strategies

[Yves Moisan]

> You need to limit DOM elements. WMS with a query-on-click works for
> that. 

Right.  The whole purpose of having features is defeated though and
that's a drag.  I'm really not fond of query-on-click to a WMS server.
I played with the clustering strategy in a bid to limit the number of
features to draw, but the calculations in the client are horrendously
slow.  Typically, I get a popup asking me if I want to keep going with
the script.  I hit yes and then I get my clusters.  For some reason
though the rendering of clusters is faster in IE7 than FF3 ?!?

I guess an option would be to calculate the clusters on the server, e.g.
set up some trigger in PG and calculate cluster tables for each discrete
zoom level.  I would then point FeatureServer to a cluster table as a
function of zoom level.  That would allow me to keep a relatively small
number of features for the DOM to deal with.

> of course, showing 1000 features won't just be a problem for IE --
> it will also be a problem for FF2, mobile browsers, eeepcs, etc. 

Agreed.

> 
> Anotehr thing I do (on the OpenStreetMap homepage) is load the data,
> then ask the user if they want to show it, if it's more than 100
> features. That way, they hae the option of making the determination of
> whether they think they can load it -- or the optino to zoom in further
> if that's what they want.

Thanx for the suggestion.

Yves