[fdo-internals] Coordinate system support for FDO

[Traian Stanev]

If it resides within providers, it means every provider would have to implement it. There are lots of providers.
If it's implemented as a utility that, say, overloads a feature reader's GetGeometry() call, then it can be used against all providers.
Same applies to raster providers, but there it would be the GetRaster call I guess.

Traian



> -----Original Message-----
> From: fdo-internals-bounces at lists.osgeo.org [mailto:fdo-internals-
> bounces at lists.osgeo.org] On Behalf Of Orest Halustchak
> Sent: Tuesday, December 18, 2007 9:05 AM
> To: FDO Internals Mail List
> Subject: [fdo-internals] Coordinate system support for FDO
>
> Hi,
>
> I'm forwarding this thread that started on the MapGuide discussion
> lists. The question is where should coordinate system transformation
> support reside, as functionality within FDO providers or as client-tier
> / viewer-tier component?
>
> There are some notes started in the FDO wiki under FDO Futures
> Discussion -> FDO Client Utilities
> (http://trac.osgeo.org/fdo/wiki/FdoClientUtilities).
>
> For anyone interested, please let us know your thoughts on this.
>
> Thanks,
> Orest.
>
> -----Original Message-----
> From: mapguide-internals-bounces at lists.osgeo.org [mailto:mapguide-
> internals-bounces at lists.osgeo.org] On Behalf Of Maksim Sestic
> Sent: Tuesday, December 18, 2007 6:11 AM
> To: mapguide-internals at lists.osgeo.org
> Subject: RE: RE: [mapguide-internals] [mapguide-users] Adding a
> CoordinateSystem to MGE/MGOS
>
>
> Hi Orest,
>
> IMHO, FDO needs that CRS part to be truly independant of the viewer
> tier
> (and some client-tier commercial products, BTW). CRS core somehow
> doesn't
> fit on viewer tier, although it's heavily used there. I've been working
> with
> SharpMap implementation where coordinate transformation engine is
> tightly
> coupled with geometry factory. When applied to FDO, you may have a
> common
> feature store CRS (if any) regularly "overriden" by simply passing new
> CRS
> type to geometry factory as a parameter, which automatically performs
> coordinate transformation on resulting geometries.
>
> I guess we should continue this discussion on FDO Futures wiki :-)
>
>
>
> Orest Halustchak wrote:
> >
> > Hi Maksim,
> >
> > The FDO Client Utilities section of FDO Futures is there for
> discussion
> > and is not an established "plan". The points included in that page
> are
> > ones that some folks have raised recently. We posted the ideas so
> that we
> > could start a discussion and get some more feedback. So, if you have
> some
> > ideas or feedback that you'd like to throw in there, please feel free
> to
> > add your comments.
> >
> > Regarding CRS support in FDO, as Jason points out, FDO doesn't do
> > coordinate transformation itself. FDO can return the CRS definition
> from
> > the data source if it is known (returned as a WKT string). That
> definition
> > is passed by MG to Proj4 or Mentor. MG relies on these libraries to
> > recognize the CRS definition.
> >
> > Thanks,
> > Orest.
> >
> > -----Original Message-----
> > From: mapguide-internals-bounces at lists.osgeo.org
> > [mailto:mapguide-internals-bounces at lists.osgeo.org] On Behalf Of
> Maksim
> > Sestic
> > Sent: Monday, December 17, 2007 4:54 AM
> > To: mapguide-internals at lists.osgeo.org
> > Subject: RE: RE: [mapguide-internals] [mapguide-users] Adding a
> > CoordinateSystem to MGE/MGOS
> >
> >
> > Jason, is there some sort of "global" OSGeo roadmap on active
> projects and
> > code being shared among them? Like - what project depends on other
> > projects'
> > deadlines, common cores (i.e. FDO in MG), etc. I guess there's a
> > geospatial
> > product manager somewhere at Autodesk who actively tracks this :-)
> > Otherwise
> > there will be lots of inner branching and wheel reinventing, but the
> > purpose
> > stays the same.
> >
> > Frankly, lack of CRS support in FDO is still mistery to me :-) MG
> should
> > be
> > able to detect and reuse any managed feature store's CRS, where
> applicable
> > (if not explicitly overriden by MG at feature source level). This
> should
> > also solve WMS/WFS troubles on WGS84 reprojection parameters and
> envelope
> > definition.
> >
> > If I understood "FDO Futures" right, there's a plan to gradually
> switch
> > general FDO architecture to client/server?
> >
> > Regards,
> > Maksim Sestic
> >
> >
> >
> > JasonBirch wrote:
> >>
> >> FDO doesn't do coordinate transformation yet.  There has been some
> talk
> >> about adding this at a "utility" layer (see the "Futures" section on
> the
> >> FDO Trac wiki) but this discussion hasn't received much attention
> yet.  I
> >> believe that this is because of time constraints on the part of
> >> interested
> >> parties, because there was a lot of interest in this at FOSS4G.
> >>
> >> Jason
> >>
> >> ________________________________
> >>
> >> From: Maksim Sestic
> >> Subject: RE: RE: [mapguide-internals] [mapguide-users] Adding a
> >> CoordinateSystem to MGE/MGOS
> >>
> >>
> >>
> >> Another thing - what about underlying FDO, shouldn't it have Mentor
> >> libraries implemented in first place? I haven't seen any 3.3.0 RFC
> >> related
> >> to it. Will Mentor implementation affect existing FDO providers?
> >>
> >>
> >>
> >> _______________________________________________
> >> mapguide-internals mailing list
> >> mapguide-internals at lists.osgeo.org
> >> http://lists.osgeo.org/mailman/listinfo/mapguide-internals
> >>
> >>
> >
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> System-to-MGE-MGOS-tp14343358s16610p14370193.html
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> >
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> users--Adding-a-Coordinate-System-to-MGE-MGOS-
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