[OpenLayers-Users] loading heavy WFS. solutions?

[G. Allegri]

I was doing it right now :-)
I was blocked by a problem while I was creating a view for the
simplified geometries. The simplify alone works fine, but with the
create view statement it returns empty... But this is something for
the PostGIS ML.

Thanks anyway for sharing the URL.

2008/9/18 percy <bjpd at pdx.edu>:
> I haven't tried this with WFS, but...
>
> I display "simplified" geometry when zoomed out with geologic map polygons.
>
> I use the PostGIS simplify(the_geom, $vertex_density) command to generate
> polygons with only one vertex every 500m, for example, when zoomed out past
> a certain extent. This is served via Mapserver using minscale/maxscale
> settings at the layer level.
>
> You can create different columns of simplified geometries for use at
> different scales (thegeom_2M, thegeom_500K, etc) in PostGIS. Or you can
> process the data and spit out different shapefiles for each scale range.
>
> Sometimes I can see some artifacts of the simplification, since topology
> constraints are not part of the process. It has a little "jagginess" like
> stained glass, but when you zoom in to see what the artifact is, I have
> substituted the high-res data and it's no longer there!
> :-)
>
> I'm pretty sure this approach will work for what you want to do. You can see
> a non-openlayers version of this here: http://ogdc.geos.pdx.edu/
>
> Cheers,
> Percy
>
> G. Allegri wrote:
>>
>> Hi list,
>> I need to load a heavy GML (the original shapefile is >12 MB), and I
>> can't make any simplification, beacuse it's composed by little,
>> needed, polygons.
>> Has ever been experimented something to do a sort of "pyramids" with
>> vectorial features? The only solution I can imagine is to produce
>> various simplifications, and then call different GMLs on the base of
>> the zoom factor... Well, it isn't a solution, it would be just a
>> horrible workaround!
>>
>> Any idea to share?
>> _______________________________________________
>> Users mailing list
>> Users at openlayers.org
>> http://openlayers.org/mailman/listinfo/users
>>
>
> --
> David Percy
> Geospatial Data Manager
> Geology Department
> Portland State University
> http://gisgeek.pdx.edu
> 503-725-3373
>