[Gvsig_english] question about gvSIG's union function

[Wolfgang Qual]

Hi Cris, list all.
Many thanks for your message and your efforts. I think that I came to the conculsion: the tools of the geoprocessing toolbox seem not to work with 3D-shapefiles:

But I have to explain this a little bit:
The original themes (see attached screenshot) were exported as shapefiles using the layer-export to shapefile dialogue from our internal geodatabase (oracle spatial, connection via geoBD). As you can see, they do not contain that much features. However, when applying the union-tool, I only got the geometry of theme1 (but expected to get both geometries in the result). Well, as you wrote that the tools were working perfectly for you, I go a little bit mistrustful. I remebered that UMN mapserver had sometimes problems when trying to display features that came from our geodatabase. The reason was that UMN mapserver was not able to display 3D-shapefiles. Therefore, we had to convert these themes into normal polygon data.

Therefore, I "consulted" the command line tool ogrinfo:
wolfgang.qual at rgu04-200:~$ ogrinfo -al /tmp/plan_gen_flaech.shp |less
INFO: Open of `/tmp/plan_gen_flaech.shp'
      using driver `ESRI Shapefile' successful.

Layer name: plan_gen_flaech
Geometry: 3D Polygon
Feature Count: 1
Extent: (4452548.810027, 5324955.409982) - (4479473.219973, 5345647.200018)

In fact, the file was a 3D polygon.


The rest was simple: convert that shapefile into a normal polygon feature using ogr2ogr:
ogr2ogr -f "ESRI Shapefile" /tmp/plan_gen_flaech2.shp -nlt POLYGON /tmp/plan_gen_flaech.shp

Afterwards, gvSIG produced the result that I expected before. Very good.
Well, I am happy to have gdal and the gdal-utilities installed on my computer (but I think that not every gvSIG user has installed it, too). Therefore, I was able to find the reason for the problem.
Therefore another wish from my side:
Wouldn't it be great to add the following functionality to gvSIG:

* possiblity to analyse shapefiles (like ogrinfo)
* possibility to make some converting-magic (3d--> "normal" shapefile)
* enhanced error messages ("Applying union-tool was not possible because of 3D-input data etc.")

Best regards,
Wolfgang
-------- Original-Nachricht --------
> Datum: Thu, 28 Aug 2008 15:00:54 +0200
> Von: Cristina Bedoya <bedoya_cri at gva.es>
> An: Users and Developers mailing list <gvsig_internacional at runas.cap.gva.es>
> Betreff: Re: [Gvsig_english] question about gvSIG\'s union function

> Hi Wolfgang, Marcus,
> 
> This bug has been unable to reproduce.
> 
> We added two layers of polygon geometry, then has been made "union" 
> geoprocessing and the result is expected, the fields of the union-layer 
> are correctly (appears the fields of the entry layer in the first 
> position and the fields of de union layer after).
> 
> The operation was conducted with layers of more than 900 records, and 
> conducting a selection of a zone of the layers.
> 
> We need more information to reproduce the possible error. As know that 
> number of records have layers you use, if you do any selection in layers 
> to merge or any other data necessary to reproduce this error.
> 
> Thank you,
> 
> Cris
> 
> 
> 
> 
> Marcus C. England wrote:
> > Hi Wolfgang,
> >
> > I have the same problem, but I remember someone mentioning that on here
> > once and I thought someone from the gvSIG team noted that it was known
> > bug.
> >
> > -Marcus
> >
> > On Wed, 2008-08-27 at 15:42 +0200, Wolfgang Qual wrote:
> >   
> >> Hi list,
> >> when trying to use the "union"-function of gvSIG's geoprocessing
> toolbox, I noticed that the result was not what I expected. Instead of creating a
> new theme, which contains all (geometry-)information of both themes, a new
> theme is generated that only contains the geometry of one input theme. I
> made several test, but everytime the same result. Now, I would like to ask
> you about your experiences with that tool - is it working for you? I am
> using gvSIG version 1.1.2 on a linux machine. 
> >>
> >> Best,
> >> Wolfgang
> >>     
> >
> > _______________________________________________
> > Gvsig_internacional mailing list
> > Gvsig_internacional at runas.cap.gva.es
> > http://runas.cap.gva.es/mailman/listinfo/gvsig_internacional
> >
> >
> >   
> 
> 
> -- 
> Cristina Bedoya Pellicé
> Proyecto gvSIG
> Conselleria de Infraestructuras y Transportes (GVA).
> Valencia (Spain)
> 
> 
> _______________________________________________
> Gvsig_internacional mailing list
> Gvsig_internacional at runas.cap.gva.es
> http://runas.cap.gva.es/mailman/listinfo/gvsig_internacional

-- 
Der GMX SmartSurfer hilft bis zu 70% Ihrer Onlinekosten zu sparen! 
Ideal für Modem und ISDN: http://www.gmx.net/de/go/smartsurfer
-------------- next part --------------
A non-text attachment was scrubbed...
Name: union_issue_pic.jpg
Type: image/jpeg
Size: 53585 bytes
Desc: not available
Url : http://runas.cap.gva.es/pipermail/gvsig_internacional/attachments/20080828/ffaf3136/union_issue_pic.jpg