[Mapserver-users] Options for spatial selects

[Ben Lewis]

Thanks Lowell,
We are ok with the javascript part. 

You mention creating temporary shape objects. Do you mean creating a
shape file and then deleting it after use or is it possible to create a
temporary shape object in memory without creating a shapefile?  We are
creating shapefiles on the fly with no problem. 

You also mention using that object in a query against a selected layer.
How does one use a shape (temporary or otherwise) to do a spatial query
against a selected layer?

Thank you much for your help.

 - Ben


-----Original Message-----
From: Lowell Filak [mailto:lfilak at medinaco.org] 
Sent: Thursday, July 15, 2004 10:31 AM
To: Ben Lewis; mapserver-users at lists.gis.umn.edu
Subject: Re: [Mapserver-users] Options for spatial selects

Sounds feasible, you may want to check JBOX & DBOX to see if a circle
shape could be incorporated into one of those before starting from
scratch if all you need are basic shapes for selecting.
More complex selection shapes may require using mapscript to generate a
temporary shape shape object to use for a query on a selected layer.

HTH

Lowell

The following message was sent by "Ben Lewis" <blewis at atsincorp.com> on
Thu, 15 Jul 2004 09:23:55 -0400.

> I have a project in which a user wants to select a bunch of features 
> on the map by creating a shape and defining a spatial query. What are 
> the options for mapserver based solutions?
>  
> One I can think of is using the tolerance value of the identify 
> function.  One would use javascript to click and drag to create a 
> circle on the screen, then send mapserver the identify coordinates 
> (circle
> center) and tolerance (circle radius) to return everything in the 
> circle.
>  
> Any other ideas? 
>  
> I know PostGIS could be used, but I'm looking for mapserver/mapscript 
> approaches, ideally using shape files.
>  
>  - Ben
>  
> _______________________________
> 
> Benjamin Lewis - Senior Analyst
> Advanced Technology Solutions, Inc. 
> Lancaster, Pennsylvania
> 717.399.7007
> http://www.atsincorp.com <http://www.atsincorp.com/>
> 
>