MapTools.org

[maplab-users] Query question

Post,Richard [NCR] Richard.Post@ec.gc.ca
Mon, 24 Nov 2003 09:47:03 -0500
Hi Matt,

I have not found a solution (I changed my query icon to represent a
rectangular query!).  That is an interesting observation about projected
verses non-projected data.  My application uses projected data as well
(LCC).  Anyone have any more suggestions we might try?

Richard Post  

-----Original Message-----
From: Matt Doggett [mailto:mdoggett@coas.oregonstate.edu] 
Sent: November 21, 2003 6:58 PM
To: mdoggett@coas.oregonstate.edu; bronsema@dmsolutions.ca;
'Post,Richard [NCR]'
Cc: Maplab-users@dmsolutions.ca
Subject: RE: [maplab-users] Query question


Allow me to shed a little more light on this problem.

- I have a map file which outputs a map in "latlong" projection (ie.
Unprojected geographic). With this map, a single click WILL return query
results.
- An identical application (same map file, data, ...everything) but
outputs a PROJECTED map, using "aea" in my case, does NOT work. Ie. You
have to click-and-drag in order for the query results to return
anything.

So, perhaps someone could explain why my Maplab application behaves
differently for projected/unprojected maps?

Matt

>-----Original Message-----
>From: maplab-users-admin@lists.maptools.org [mailto:maplab-users- 
>admin@lists.maptools.org] On Behalf Of Matt Doggett
>Sent: Friday, November 21, 2003 3:31 PM
>To: bronsema@dmsolutions.ca; 'Post,Richard [NCR]'
>Cc: Maplab-users@dmsolutions.ca
>Subject: RE: [maplab-users] Query question
>
>I noticed that I have this exact same behavior. Changing the MIN_RECT 
>appears to have no effect.  I was wondering if you discovered any 
>solution to this problem? Would be nice to have working queries without

>having to drag the mouse all the time.  Having to click-n-drag inside a

>polygon to select that polygon seems kind of silly.
>
>Matt
>
>>-----Original Message-----
>>From: maplab-users-admin@lists.maptools.org [mailto:maplab-users- 
>>admin@lists.maptools.org] On Behalf Of William A. Bronsema, C.E.T.
>>Sent: Friday, October 17, 2003 4:36 AM
>>To: Post,Richard [NCR]
>>Cc: Maplab-users@dmsolutions.ca
>>Subject: Re: [maplab-users] Query question
>>
>>Hi Richard,
>>
>>I'm not sure if this will help or not, but FYI -
>>
>>There is a constant defined in the globprefs.php file for your 
>>gmapFactory application that should look something like this ( In my 
>>version it is on line 65):
>>
>>define( "MIN_RECT", 5 );
>>
>>This constant controls the difference between a "point click" and 
>>"rectangle select".  Essentially all interactions with the map are 
>>"rectangle selects".  This constant tells the application the
threshold
>>at which the user was intending to perform a "point click" (i.e. a
tiny
>>rectangle) instead of a "rectangle select".
>>
>>In the case of querying, if the value is too small then more often
than
>>not a tiny rectangle query will be performed instead of a point query 
>>which can lead to confusing results.
>>
>>HTH.
>>
>>Regards,
>>Bill
>>
>>
>>--
>>
>>William A. Bronsema, C.E.T.
>>Applications Developer
>>
>>DM Solutions Group Inc.
>>http://www.dmsolutions.ca ____________________________________
>>
>>Post,Richard [NCR] wrote:
>>> Hello,
>>>
>>> I have a small problem with my gmapfactory application.  The
>application
>>> uses the query function to select points from a shape file.  The
>problem
>>> is that the query only works when you drag a box over the points
(ie.
>>> Doing a rectangular query).  When you simply click on the point
>nothing
>>> is selected (ie. The layer does not return any results).  I have
>already
>>> tried changing the TOLERANCE and TOLERANCEUNITS in the map file,
>which
>>> does not seem to have any effect.
>>>
>>> Any suggestions would be welcome.
>>>
>>> Thanks,
>>>
>>> Richard Post
>>> Environment Canada
>>>
>>
>>
>>_______________________________________________
>>Maplab-users mailing list
>>Maplab-users@lists.maptools.org 
>>http://lists.maptools.org/mailman/listinfo/maplab-users
>
>_______________________________________________
>Maplab-users mailing list
>Maplab-users@lists.maptools.org 
>http://lists.maptools.org/mailman/listinfo/maplab-users



This archive was generated by Pipermail.