request for comments...

[Paul Cameron]

I am very much in favor of seeing something like this implemented. I'm 
got an app running now that sounds very similar to the HILITE mode but 
its a very convoluted process that I'd love to be able to clean up. I've 
got a couple comments/questions on them below.

On Fri, 8 Oct 1999, Stephen Lime wrote:

> NORMAL - with this style the results of the query would be used to define
> a map extent and then the map would be draw as normal with no special
> attention payed to the query polygons. This would allow for item/value
> queries to generate a map in one step rather than the current two. Embedding
> maps if you know nothing about coordinates would be much easier this way.

If I understand this correctly than this will remove the problem of 
having to know the mapextent of a polygon that we want to zoom to. Will 
we be able to specify a different mapfile for the new map that will be 
created? This would be very useful for nesting interfaces together.

> 
> HILITE - the map would be drawn as normal, but features that are part of
> the query result set would be drawn using the hilite color. Very ArcView-ish.

I envision this working by passing an array of selected features to 
mapserv which would color them in for me. Will we be able to specify the 
color used in the hilite and can we make the highlight color transparent? 

This one might be stretching but for the application I've got going right 
now I need to break the highlighted features into different classes. 
Could multiple classes be supported, possibily using hashes in perl?

I'm also curious how this will be integrated into mapscript. I don't 
know how mapscript will be work but I could see this being closely tied 
to using mapscript. 

paul

> 
> SELECTED - for queried layers, only those features that are part of the 
> result set would be drawn. They would be rendered normally with no hilites.
> Especially useful with item/value queries. Non-query layers would be drawn
> as normal.
> 
> Note that queries are limited to shapefiles only. Tiled data is not queryable.
> 
> (Using perl and data from other sources will in effect give you query access
> to those sources since drawing is done feature by feature.)
> 
> Anyway, I'd like to get comments from folks on this extension. Other ideas and
> so on. I can envision some very sophisticated apps just using what I've outlined
> above.
> 
> Steve
> 
> Stephen Lime
> Internet Applications Analyst
> MIS Bureau - MN DNR
> 
> (651) 297-2937
> steve.lime at dnr.state.mn.us
>