[Gvsig_english] Fwd: PostGis + 3D extension
Nicklas Avén
nicklas.aven at jordogskog.no
Wed Jan 19 14:48:56 CET 2011
sorry about off list posting
On Wed, 2011-01-19 at 14:35 +0100, Jordi Torres wrote:
> Hi Nicklas,
>
> Please, let' s take this conversation "on-list". The attacments did
> not pass the list control, that's the reason why I wrote to you
> directly.
> About generating 3D datasets it's simple if you have the data in .shp
> (using shp2pgsql). That's the way I get my data.
> In the other hand, a polygon cannot be in more than one plane in 3D,
> if this is the case, this structure must be tessellated into triangles
> or at least polygons in the same plane.
Well, what do you mean by cannot be in more than one plan?
I understand that it cot can when it comes to rendering and so on.
And it cannot when it comes to valid polygons.
But you can express a polygon in wkt that has vertexpoints in more than
one plan.
for example:
POLYGON((0 0 0,0 5 0, 0 5 5, 10 5 5, 10 5 0, 10 0 0, 0 0 0))
In many examples the result is undefined and impossible to decide
without more information and that's why I have to deal with it in
distance calculations and send an error msg instead of trying to
calculate the distance.
Or am I missing something?
Regards
Nicklas
> (the same as openGL do when rendering concave polygons). May be the
> tesselator included in the 3D extension eats this kind of structure,
> but I don't trust.
>
> About PostGis I am a noob or less than a noob. I only know the basics
> to set a database and do a sql query. And I learned it yesterday :). I
> am a 3D developer, and postgis is a tangential theme for me. So for
> the questions about postGIS ask to the gurus in the list... ;)
>
> Cheers.
>
>
> 2011/1/19 Nicklas Avén <nicklas.aven at jordogskog.no>
> Yes, that would be nice :-)
>
> It is a little bit difficult to create 3D datasets I think, at
> least if
> the polygons contains more than 3 points (counting the first
> and last as
> 1) because they have to be in the same plan. That is the part
> in the 3D
> distance code that I am most worried about. Now there is no
> real test if
> people sends polygons not on one single plan to the function,
> because
> such a test is quite expensive to calculate if the polygon has
> many
> points. Also there have to be some tolerance.
>
> Have you tried the PostGIS trunk lately?
>
> It will be interesting to test and visualize
> st_3d_shortestline through
> gvSIG.
>
> Cheers
> Nicklas
>
>
> On Wed, 2011-01-19 at 13:55 +0100, Jordi Torres wrote:
> > Hi Nick,
> >
> > Is a lot of triangular separate polygons, if you want the
> archive to
> > do testing I can send it to you.
> >
> > Cheers.
> >
> > 2011/1/19 Nicklas Avén <nicklas.aven at jordogskog.no>
> > Thanks a lot
> >
> > I will try it as soon as possible. When I have this
> woking
> > there will be
> > a blog post about this extension and comming 3d
> distance
> > functions in
> > postgis.
> >
> > Is TIN supported? or is it a lot of triangular
> separate
> > polygons in the
> > example picture?
> >
> > Great work!
> > Thanks
> >
> > /Nicklas
> >
> >
> >
> > On Wed, 2011-01-19 at 13:47 +0100, Jordi Torres
> wrote:
> > >
> > >
> > > ---------- Forwarded message ----------
> > > From: Jordi Torres <jtorresfabra at gmail.com>
> > > Date: 2011/1/19
> > > Subject: Re: [Gvsig_english] PostGis + 3D
> extension
> > > To: Users and Developers mailing list
> > > <gvsig_internacional at listserv.gva.es>
> > >
> > >
> > > Hi Nicklas,
> > >
> > > Here you have attached a zip file. Substitute the
> jars in
> > the way Fran
> > > told to you.
> > >
> > > And congrats to jaspa teams!! Good work!
> > >
> > > Cheers.
> > >
> > > 2011/1/19 Francisco José Peñarrubia
> <fpenarru at gmail.com>
> > >
> > >
> > > Hi.
> > >
> > > I just want to remark and say thanks to
> JASPA team,
> > who did
> > > the hard work of this patch in gvSIG
> Sprint. I hope
> > we can use
> > > it in 1.11 release.
> > >
> > > http://jaspa.forge.osor.eu/
> > >
> > > Best regards.
> > >
> > > Jordi, please, can you send the latest
> jars to
> > Niklas?. I will
> > > create a patch and upload it to the
> repository.
> > >
> > > El 19/01/2011 13:30, Jordi Torres
> escribió:
> > > >
> > > > Hi Nick and Fran,
> > > >
> > > > I have started a new thread in the list,
> this way
> > we won't
> > > > merge topics.
> > > >
> > > > Fran has fixed the issues and now we are
> able to
> > see 3D
> > > > geometries using postigs (attached is a
> screenshot
> > of a 3D
> > > > polygons layer). By the way, polyhedral
> is not
> > supported by
> > > > gvSIG postGis driver (even I don't now
> if it is
> > OGC
> > > > compliant), so you have to decompose it
> in
> > polygons.
> > > >
> > > > Cheers!
> > > >
> > > > --
> > > > Jordi Torres Fabra
> > > >
> > > > gvSIG 3D blog
> > > > http://gvsig3d.blogspot.com
> > > > Instituto de Automática e Informática
> Industrial
> > > > http://www.ai2.upv.es
> > > >
> > > >
> > > >
> _______________________________________________
> > > > Gvsig_internacional mailing list
> > > > Gvsig_internacional at listserv.gva.es
> > > >
> >
> http://listserv.gva.es/cgi-bin/mailman/listinfo/gvsig_internacional
> > >
> > > --
> > > Fran Peñarrubia
> > > Scolab
> > > www.scolab.es
> > >
> > > Asociación gvSIG
> > > www.gvsig.com
> > >
> > >
> _______________________________________________
> > > Gvsig_internacional mailing list
> > > Gvsig_internacional at listserv.gva.es
> > >
> >
> http://listserv.gva.es/cgi-bin/mailman/listinfo/gvsig_internacional
> > >
> > >
> > >
> > >
> > >
> > > --
> > > Jordi Torres Fabra
> > >
> > > gvSIG 3D blog
> > > http://gvsig3d.blogspot.com
> > > Instituto de Automática e Informática Industrial
> > > http://www.ai2.upv.es
> > >
> > >
> > >
> > >
> > > --
> > > Jordi Torres Fabra
> > >
> > > gvSIG 3D blog
> > > http://gvsig3d.blogspot.com
> > > Instituto de Automática e Informática Industrial
> > > http://www.ai2.upv.es
> >
> >
> >
> >
> >
> >
> > --
> > Jordi Torres Fabra
> >
> > gvSIG 3D blog
> > http://gvsig3d.blogspot.com
> > Instituto de Automática e Informática Industrial
> > http://www.ai2.upv.es
>
>
>
>
>
>
> --
> Jordi Torres Fabra
>
> gvSIG 3D blog
> http://gvsig3d.blogspot.com
> Instituto de Automática e Informática Industrial
> http://www.ai2.upv.es
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