queryUsingPoint problems

[Daniel Morissette]

Hi,

I have used the $map->queryUsingPoint() for quite a while and I know it
works for sure.

However, for a layer to be queryable, its status must be ON or
QUERYONLY, and it must have a QUERYITEM and at least one QUERY object,
otherwise it appears to be ignored in the query:

  LAYER
    ...

    QUERYITEM "anyfield"
    QUERY
      EXPRESION /./
      TEMPLATE "ttt"
    END
  END 


BTW, there is a mistake in the PHP documentation, I'll fix it.  The
method does indeed return a queryResultObj, and the pointObj (query
location) should be specified in georeferenced map coordinates, not
pixels.

I hope that helps,
-- 
------------------------------------------------------------
 Daniel Morissette                       danmo at videotron.ca
              http://pages.infinit.net/danmo/
------------------------------------------------------------
  Don't put for tomorrow what you can do today, because if 
      you enjoy it today you can do it again tomorrow.


"Doyon, Jean-Francois" wrote:
> 
> Hello,
> 
> I too seem to be having problems ... using the PHP/Mapscript, the querying
> methods
> don't seem to be returning an object (queryResultObj, I would expect) ... I
> don't get any
> errors from the query method (
> $layername->queryusingpoint($point,MS_SINGLE,-1) )
> either ... $point IS a pointObj with X and Y in the projection cooridnate
> system (i.e. not
> in pixels).
> 
> And so far, whether I query the map or the layer, the result is allways "0"
> (the number zero).
> 
> The docs say the method queryUsingPoint should return void, is that right ?
> Seems to me
> it should return a queryResultObj ...
> 
> I'm stumped ... Anybody ?
> 
> J.F.
> 
> > ----------
> > From:         Sean O'Hagan[SMTP:seano at metavera.com]
> > Reply To:     Sean O'Hagan
> > Sent:         Wednesday, September 06, 2000 2:55 PM
> > To:   MapServer List
> > Subject:      queryUsingPoint problems
> >
> > Hello:
> >
> > I'm having some problems with queryUsingPoint. The 'numresults' and
> > 'numquerylayers' members of the returned qryResultObj seem to be
> > undefined.
> > My print statements in the code below show no values. Is my syntax
> > incorrect? Thanks very much in advance.
> >
> > Sean.
> >
> >
> > #!perl
> > use mapscript;
> >
> > # getShapesNear( map_file, x_coord, y_coord, layer_number, max_shapes )
> > sub getShapesNear {
> >
> >   my @shapes;
> >   my $point = new pointObj();
> >   my $qryResult;
> >   my $mapfile   = new mapObj($_[0]);
> >   $point->{x}   = $_[1];
> >   $point->{y}   = $_[2];
> >   my $layerNum  = $_[3];
> >   my $numShapes = $_[4];
> >
> >   $qryResult = $mapfile->queryUsingPoint($point, MS_MULTIPLE, -1);
> >   $j = 0;
> >
> > print "Number of shapes on all layers: $qryResult->{numresults}\n";
> > print "Number of layers searched: $qryResult->{numquerylayers}\n";
> >
> >   for (my $i=0; $i<$qryResult->{numresults}; $i++) {
> >     my $shpResult = $qryResult->next();
> >     if ($layerNum == $shpResult->{layer}) {
> >       @shapes[$j++] = $shpResult->{shape};
> >     }
> >   }
> >   $qryResult->{free};
> >   return @shapes;
> > }
> > @closeStops = getShapesNear( 'mapfile.map', 923072.8083, 523859.9862, 2,
> > 0 );
> > print "RecNum: @closeStops[0]\n";
> > exit;
> >
> >