Re: [udig-devel] Spatial Operation and Editing Tools

[Victor Mauricio Pazos <mauricio.pazos@xxxxxxxx>]

Thanks Paul, I reply below

Best Regards

On Tuesday 05 December 2006 20:11, Paul Ramsey wrote:
> Looks great...
> - Is there any way we can genericize the act of "creating new
> features based on an operation" so that all the tools that do that
> use the same basic UI?

We identified some commons steps and commons functionalities in the work flows 
of different  operation (in the architecture you can see that in "pages" 
and "common" utility package). We can think in abstract work flow for 
operation like:

- check preconditions operations (different, ie: "one F selected", "two or 
more F selected", etc)

- parameters capture ( wizard ui ) (could reuse some wizard page, but there 
are user desition that will require specials wizard page)

- execute transaction (based in uDig commands  )

We could think in this pattern as "template method" for abstract operation, 
then each step could be extended for operation implementation (operation 
instances).

I think to reach a good abstraction is very important to maturity the design 
and implementation. I suppose at the final of this iteration we can do an 
abstraction work and refactoring actions to obtain some generalizations.
 

> - For merging, there are a number of a separate, similar use cases:
> o Merge adjacent polygons based on an attribute value.  The
> equivalent to the SQL statement "select geomunion(the_geom) from tbl
> group by attrA".

> o Merge adjacent polygons based on "minimum change". The idea being
> similar to "sliver removal".  Combined with attribute aggregation,
> this is potentially a powerful tool, but a little different from your
> case.

I think uDig requires a selection tool, that allows to define a query, then 
udig can process it and shows as selected the features. Some days ago we 
debated about a selection tool that can use OGC CQL as input language, and an 
editor (syntax conduced) . Then we could compose this "Selection Tool" 
and "Spatial Operations" (or other action).

An scenario could be the following: 
 - CQL Filter definition: "adjacent features and attributeX > 100"
 - Apply operation: select Merge  

>
> Paul



>
> On 5-Dec-06, at 11:00 AM, Victor Mauricio Pazos wrote:
> > Hi list!, we have begun a project to develop Spatial Operations and
> > Editing
> > Tools features. This new features will be LGPL products.
> >
> > Our first goal are Spatial Operation (buffer and merge). The
> > following link
> > has the project details.
> >
> >  http://udig.refractions.net/confluence/display/COM/Axios
> >
> > We expect yours comments.
> >
> > Thanks in advance
> > --
> > Mauricio Pazos
> > _______________________________________________
> > User-friendly Desktop Internet GIS (uDig)
> > http://udig.refractions.net
> > http://lists.refractions.net/mailman/listinfo/udig-devel
>
> _______________________________________________
> User-friendly Desktop Internet GIS (uDig)
> http://udig.refractions.net
> http://lists.refractions.net/mailman/listinfo/udig-devel

-- 
Mauricio Pazos
Director

Axios Engineering
www.axios.es
e-mail: maurcio.pazos@xxxxxxxx
tel-:+34 94 441 63 84
fax: +34-94 441 64 90