some questions

[Stephen Lime]

> >From mapadm at polsl.gliwice.pl Thu Apr  1 08:42:38 1999
> From: "Grzegorz Myrda" <mapadm at polsl.gliwice.pl>
> To: mapserver-users at lists.gis.umn.edu 
> Date: Thu, 1 Apr 1999 16:44:01 +2
> MIME-Version: 1.0
> Content-transfer-encoding: 7BIT
> Subject: some questions
>
> Hello folks,
>
> Maybe I will start ...
>
> What is the difference between "imgsize" and "mapsize" parameter
> for mapserv.cgi ?

imgsize, and all parameters starting with "img" refer to an existing image
in a users web browser. mapsize, and all parameters starting with "map"
refer to the map/image to be created. The reason for both parameters is
to allow for changing of image sizes without editing a mapfile. A common
use would be to use one size for an interactive application and then switch
to a larger size for printing.

> Is this possible to scale (change size depending on scale) and at
> the same time classify (also change size) in version 3.2x ?

If I understand the question, then sure. The only difference between
older versions and 3.2 is that now you can't control color, symbol and
size independently, i.e. with separate attribute lookups. In exchange you
get much better label control. To turn on scaling set the parameter
SYMBOLSCALE for a layer. This will scale symbols and fonts based
on the ratio between the scale of the map being created and the value
for SYMBOLSCALE. This is true for all defined classes. Note that only
certain types of symbols (ellipse and vector) are scalable. 

> How can I show multiple results of "nitemquery" ? If I use
> "itemquery" it's simple: I use "shpext" on template.
> But what if there are more than one result and I would need to
> place more "shpext's" on template ?

URL templates cannot be used for presenting multiple results. The page
a user see's when multiple results are returned is actually built from a
number of files. Here's the order they are sent:

1) web HEADER

2) layer HEADER
3) query TEMPLATE
4) repeat 3) for each result for a given layer
5) layer FOOTER

6) repeat 2) through 5) for each layer with results

7) web FOOTER

Note that feature attributes are only available for substitution in step 3). In general,
HEADERs and FOOTERs are small files that inject section titles or other HTML spacing
code. It's possible to use 1) through 6) to initialize a bunch of javascript and actually
build the page in 7). It's not too hard, and very flexible, once you get the hang of it. Here's
an example URL that show's off many of the query options in 3.2. The interface uses
javascript/java so a version 4.x browser is recommended.

http://ftp.dnr.state.mn.us/cgi-bin/mapserv?map=search/search.map&layer_select=county&category=10

It's a front-end for a large GIS data distribution site we're running. It uses an out-of-the-box
version of 3.2 and javascript to make the UI more friendly. Java is used to support box zooming
and queries. I'll glady share any config files with interested users. The java applet will be posted
on the mapserver homepage.

> Happy Easter!
>
> Grzegorz
> mailto:mapadm at polsl.gliwice.pl 

Steve

Stephen Lime
Internet Applications Programmer
MIS Bureau - MN DNR

(651) 297-2937
steve.lime at dnr.state.mn.us