search and zoom - II

Stephen Lime steve.lime at dnr.state.mn.us
Mon Nov 15 23:30:20 EST 1999


This can be done a couple of ways. 3.2 and 3.3 support and itemquery mode (also itemnquery) in which you supply two form vars one called "item" which is the name of an attribute and another called "value" which is a regex to use for matching. Often a 3rd variable, "qlayer" is used to identify the layer to be searched although this is not required. As with any query, individual shape bounding boxes and centroids (box center, not the actual centroid) are available to the query template. It's easy to use these to generate new maps specific to a shapes extent or by using the centroid and a scale. In 3.2, this is the only way to do this.

3.3 extends this capability by introducing what are termed querymaps, that is visualization of a query. They allow you to zoom in on selected features using extents or centroids, you can highlite selected features in a special color, can draw just the selected features. Lots of potential here but it's a new feature and one I'm still finishing. It's pretty much fully supported for
the itemquery modes. Mapext=shapes is a brand new option for generating extents based on selected features. All of this will be in the test suite. 

Steve

<<< Ma <marin at here.is> 11/15  8:26p >>>
Dear All,
I need to search a name (for example of a place) and
if the system find it - to zoom on it: How to this in mapserver3.3?

I mean search and zoom of small objects - points, short lines, small
polygons, etc. It will be good idea the scale factor of the zoom to be
fixed for all queries, i.e. it will be good if the scale factor doesn't
depend of the size of the object, i.e. shape extend (for example - not
this: "mapext=shapes")

Any help?

--
Ma







More information about the mapserver-users mailing list