Christian Müller ha scritto:
> Andrea, can we agree on 3 terms
> 1) Vertical Generalization
> Having multipe stuctural indentical features
> 2) Horizonalt Generalization
> Having mulitple geometry properties

Hmmm... I don't feel the need to make up terms for this, but
if you'll use them, I'll know what you mean.

> 3) Dynamic Generalization
> Delegating the work to a backend (Btw, we have to include generalization 
> into jdbc-ng)

We could, but we don't have to. I made some tests time ago and doing
Douglas-Peuker on the fly generalization inside postgis, and it gave me
no speedup (on the contrary, it was so slow that it made WMS rendering
slower, with a PostGIS database sitting on the other side of a
100Mbit home network). That's why I'm pushing for the non topology
preserving case too, it's the only generalization technique that
could make on the fly, in database generalization worthwhile.

> As you pointed out, we will need some config file (I would prefer XML). 
> Nevertheless I should be possible to read this config from anywhere 
> else. This was my idea with a " "GeneralizationFinder". The default 
> implementation should do the file stuff.
> To tell the truth, until know I spent most of my time in geotools, so I 
> am completely new to the concept of the Catalog and the ResourcePool.
> The data store wrapper sounds good ,but first,we should make a data 
> acess wrapper. I dont want to support modifications at this point in time.
> If we implement this wrapper class, is there a need for  DataStore 
> (DataAccess) and  the correspoinding factory class ?.
> As you see, I am quite uncertain about the starting point, the creation 
> of the wrapper object.

First off we need to hear back from other devs as this would be a core
modification in a very core class, then we'll decide how to handle
this. Anyways, the two most promising routes seem to suggest the
usage of a DataStore wrapper (whether we need a factory or not, it's
up to how the hooking is made).
Also, if the datastore wrapper is made in GeoServer you can limit
yourself to a handful of methods (no need to worry about the
reader/writer methods DataStore provides, GeoServer does not use them),
and throw unsupported operation exceptions for the others.
Finally, yes, it's ok if the pre-generalized data is returned read-only.

Cheers
Andrea

-- 
Andrea Aime
OpenGeo - http://opengeo.org
Expert service straight from the developers.

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