labelObj in mapscript ?

Doyon, Jean-Francois Jean-Francois.Doyon at CCRS.NRCan.gc.ca
Wed Jun 28 06:58:27 PDT 2000


Allright, I couldn't easily get the ACTUAL datatype of the columns (The Perl
XBase module doesn't give you those for some reason), so I just went ahead
and tried.

Turns out those parentheses make a big difference ! They make things work !

I tried successfully ([ELEV_RANGE] = 60) , ([ELEV_RANGE] = 60.0) ,
([ELEV_RANGE] > 20) ...

But of course the minute I remove the parentheses, nothing works. Didn't see
this in the docs, and it seems a bit strange behavior, since parentheses are
usually used for grouping, but hey if it works, it's fine by me.

Thanks a bunch, as allways :)
J.F.

> ----------
> From: 	Stephen Lime[SMTP:steve.lime at dnr.state.mn.us]
> Sent: 	Tuesday, June 27, 2000 11:13 PM
> To: 	Jean-Francois.Doyon at CCRS.NRCan.gc.ca;
> mapserver-users at lists.gis.umn.edu
> Subject: 	RE: labelObj in mapscript ?
> 
> What xbase type is LEVEL_RANGE? All equality tests are done using string
> comparisons. With integers and char fields this is no problem but with
> floats it can become a hassle although equality tests with floats have
> been rare in my travels. What happens with that the database coughs up
> "60.00000" which doesn't match "60". Would've thought the logical
> expression:
> 
>   ([LEVEL_RANGE] = 60.0)
> 
> would've worked. Will have to test that.
> 
> Anyway, if LEVEL_RANGE is a float then using a regex like EXPRESSION
> /^60.*/ might solve the problem.
> 
> If this suggestion doesn't help then please pass along the shapefile (or a
> portion thereof).
> 
> Steve
> 
> <<< "Doyon, Jean-Francois" <Jean-Francois.Doyon at CCRS.NRCan.gc.ca>  6/27
> 3:07p >>>
> Thanks, that fixed the problem right away !
> 
> Now, same KINd of problem, but with a twist.
> 
> I am now trying to map elevation levels.
> 
> In order to do this, I set a CLASSITEM of LEVEL_RANGE in my case.
> 
> Then I define various classes with different EXPRESSION statements. Right
> now I just have one that says "60", which basically would mean : draw alll
> the polygons that have a LEVEL_RANGE of 60, right ?
> 
> Well, no such luck. It keeps drawing the whole country ! (or, at times,
> nothing at all).
> 
> So, what am I doing wrong ? I've successfully used CLASSITEM and
> EXPRESSION
> allready to draw the provinces and territories different colors.
> (CLASSITEM "NAME"  , EXPRESSION "Ontario" , EXPRESSION "Quebec" , etc ...)
> 
> I tried setting the "annotate" flag, no dice. I tried using a type of
> "Polygon" and "Annotation" without success.
> The rendering allways takes a while though (i.e. it IS doing something).
> 
> I was wondering if the datatype might be a concern (since, as you might
> remember, all this configuration information comes from a DB Backend), but
> after playing with that, it didn't help. (i.e. 60 or '60' or '[ELEV_RANGE]
> =
> 60' , etc ...)
> 
> I'm out of ideas ... anyone ?
> 
> BTW, Stephen, thanks for thet Proj.pm ... I haven't tried it yet, but I
> was
> looking for such a beast, might want to officially release it someday !
> 
> Jean-Francois Doyon
> Internet Service Development and Systems Support
> GeoAccess Division
> Natural Resources Canada
> (613) 992-4902
> 
> 
> 
> > ----------
> > From: 	Stephen Lime[SMTP:steve.lime at dnr.state.mn.us]
> > Sent: 	Thursday, June 22, 2000 3:34 PM
> > To: 	Jean-Francois.Doyon at CCRS.NRCan.gc.ca;
> > mapserver-users at lists.gis.umn.edu
> > Subject: 	RE: labelObj in mapscript ?
> > 
> > This probably has to do with an internal annotation flag that is set
> when
> > the mapfile is read. In cases where the decision to annotate is set
> after
> > the mapfile is loaded then then flag isn't set and annotation won't be
> > done.
> > This has been remedied in the latest CVS (which I would avoid until
> > next Monday unless you're desperate).
> > 
> > For now there are a couple of workarounds. If you're using a mapfile
> > with all layers predefined then you can define a dummy classitem
> > property or class text porperty. This is suffiecient to set the annotate
> > flag.
> > Since your building the entire map from scratch you'll need to set the
> > flag 
> > by hand for each layer that has annotation. Use something like:
> > 
> >   $layer->{annotate} = 1;
> > 
> > and see if that fixes things. Again this has been fixed in the latest
> > code.
> > 
> > Use $class->{label}->{outlinecolor} rather than backgoundcolor. Both
> > keywords
> > do the samething, but I had to choose one name for the C structures.
> > 
> > Steve
> > 
> > Stephen Lime
> > Internet Applications Analyst
> > 
> > Minnesota DNR
> > 500 Lafayette Road
> > St. Paul, MN 55155
> > 651-297-2937
> > 
> > >>> "Doyon, Jean-Francois" <Jean-Francois.Doyon at CCRS.NRCan.gc.ca>
> 06/22/00
> > 01:56PM >>>
> > Thanks a bunch ...
> > 
> > Now, I'm just stumped ...
> > 
> > I've setup a system where the mapfile type parameters are now stored in
> a
> > database (At least all the ones that I can).
> > 
> > So it cycles through the database, determining classes and labels and so
> > on
> > .. It's been working well so far. I've managed
> > to color all canadian provinces and territories using a classitem and an
> > expression, and storing all the classes in the DB
> > and so on. Now I'm trying to generate an annotation layer that is the
> city
> > names, but I'm having no luck, the labels simply
> > won't draw 
> 



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