[OpenLayers-Users] SelectFeature

[Lourens Veen]

On Tuesday 09 October 2007 19:57:13 staff-gmail wrote:
>
> Selection by lat/lon can be done by using a point in polygon
> algorithm which we've found to be pretty fast (it is in java and c++,
> we'll see in Ruby).

Well, for an OL client-side tool it would have to be JavaScript. But of 
course, the language doesn't affect the complexity of the algorithm.

> Using this selection method allows you to 
> specify which object groups you're testing on which means you can
> filter down the search space and avoid the "layers" problem.

Whoa, now you're going too fast. You would still need to have some kind 
of spatial index for that, right. If you're going to exclude groups of 
objects, you need to know that you can do that without throwing away 
solutions.

> And if you name your svg element id's with the database id's, then
> your lat/long lookup can be translated back to a DOM operation, if
> that makes any sense.

So you propose to send the mouse click to the server, do the lookup 
server-side, and then send the resulting features back to the client?

Then you might as well use a WMS and query it...

Lourens

-- 
          ir. Lourens Veen          University of Amsterdam - IBED
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