newbie questions

[Stephen Woodbridge]

Timothy,

To place an ellipse on the map you will need to convert it to a polygon, 
at least for mapserver. I think I would look at PostGIS as a starter 
because it would allow you to store you ellipses and a rational table 
and allow you to do a lot of dynamic filtering. You could also write a 
simple stored procedure the could convert your ellipse definition into a 
polygon that can be displayed by mapserver. PostGIS gives you the 
ability to use SQL to define you LAYER DATA statement which is very 
powerful. Also you can easily set up dynamic CLASS attributes that make 
it easy to do thematic maps where objects are rendered and styled based 
on attributes.

Clicking on the map and getting another page to display is well 
documented on the mapserver documentation and can be done with image 
maps or by setting up QUERY layers.

Read this for more information:
http://mapserver.gis.umn.edu/community/conferences/MUM3/workshop/postgis/
and some good examples.

-Steve W.

Stack, Timothy G. wrote:
> So I'm new at most of this mapping stuff. I've been playing around with 
> a number of free GIS tools, and gone through a bit of their 
> documentation and tutorials (MapServer, GeoServer, MapBuilder, ka-map, 
> TimeMap, OpenMap...). With all of these I've gotten to the point where I 
> can put an interactive map on a webpage. But I haven't been able to 
> figure out the next step.
> 
>  
> 
> The goals of my team's project right now are:
> 
> 1) We need a webpage with a map of the world (for now, I think we'll get 
> the world map from some public WMS)
> 
> 2) It needs to be very interactive (thus my interest in MapBuilder and 
> ka-map)
> 
> 3) We need to take our own data (which could be in any format) and put 
> it on the map. Right now, this will be in the form of ellipses drawn at 
> certain coordinates. The ellipses will need to be to scale (eg. if it 
> has a major axis of 30 miles and a minor axis of 10 miles, we will need 
> to draw it that size on the map). Putting icons on the map will probably 
> be important later on.
> 
> 4) We will need to be able to filter what data is shown on the map (or 
> perhaps highlight certain objects). The filter could be "all data in 
> this bounding box" or "all objects that have property X".
> 
> 5) We need to be able to click on objects in the map and have 
> information about them show up in another part of the webpage, or even 
> have the selection registered on the server to affect other programs.
> 
>  
> 
> As I said, I can put a map in a webpage. I think the next step is to 
> take our ellipse data and show it on the map. This is what I've been 
> searching and searching for, and I can't seem to find the right 
> documentation to get me started. I'm guessing that I'll need to use 
> something like MapServer, somehow tell it the coordinates of ellipses or 
> groups of line segments, and let it create images for my ellipse layer. 
> Is that right? Can anyone get me started and point me to some 
> documentation that will get me there?
> 
>  
> 
> For number 4, filtering, I'm thinking that I would have to apply the 
> filter to some data set of ours (maybe set a visible/highlighted flag 
> for each entry in a database), then have my map server rebuild the layer 
> and refresh the client.
> 
>  
> 
> For number 5, selection, my guess is that I need a WMS to take the click 
> and do something like a GetFeature request. From there, I'm not sure how 
> the data gets where it needs to go.
> 
>  
> 
> Again, any documentation you could point me to for these types of things 
> would be great. If there are any other map tools that you think would 
> fit, let me know. We would really like to use google's maps API, but I 
> think it's against their terms of use to put it in a proprietary product 
> or keep it on a private network.
> 
>  
> 
> I know that was a lot, but I appreciate any help you can offer. Thanks.
> 
>  
> 
> Tim
> 
>  
> 
>  
>