[Mapserver-users] fully featured GIS and "mapserver vs GRASS GIS" {Scanned} {Scanned}

[Siki Zoltan]

On Sun, 4 Apr 2004, Saurabh Data wrote:

> Dear Zoltan
> 
> Thanks for your email.
> 
> Regarding overlay : In the Demo , mapserver can make use of overlaying i.e. 
> it displays cities and roads on the same map. Can you give me more 
> information on that ?.

Overlay in GIS has different meaning. Overlay is a special GIS operation
with to operands (layers) and creates a new layer. See some books on
introduction to GIS.


> The demo also mentions about "query by feature" and , "query multiple 
> features" , what are they for ?

Click on the map and you can get the attributes of the selected entity or
entites.
> 
> as you said that analysis is not involved, does it make use of of other tool 
> called "network analysis" ?
> 
You can use any analysis tool separate from mapserver. Mapserver can
publish the results. You have the chance to extend mapserver functionatity
using PHP or other scripting, programming environment...

> ALso, as said on the mapserver homepage, it uses quadtree spatial indexing . 
> I couldnt find any more relevant information on the documentation page. IS 
> there anything mentioned elsewhere ?

Quadtree is not specific to mapserver. It is a general method to speed up
displaying graphical information. You can find many info on the net about
quadtrees.

Bye 
Zoltan