Quantum GIS and cadastre

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Quantum GIS and cadastre

Beowulf
Hi! I'm fairly new to this, so this is probably a newbie question :)

I live and work in Ukraine. Our company works with land on a local scale. That means that we do surveys of people's land plots (with a tacheometer) and do all kinds of stuff with that information. First we need to convert the field traverse into the coordinates of individual points. Then we need to put those points on a map. Also, we need to supply these land plots with a bunch of information (like who is the owner of the plot and what limitations on the use of the land are in place and so on). And finally we print reports like the cadastre plan. And create an exchange file (special format) with all the data to upload it to the main cadastre base.

The way we do it now is REALLY ugly. It's done with a bunch of buggy, kludgy assorted tools. I am trying to set this all straight, and here's my question. Can QGIS be a good platform for this? Here are the requirements:

1. The GIS is open source, free.
2. It can associate data with objects on the map. The data is in a relational DB and can be queried.
3. It can display vector data and raster data reasonably fast (not slower than AutoCAD).
4. Plugins can be written for it, for instance a plugin to convert field traverse report to coordinates, a plugin to conveniently fill all the information for a land plot (a form), etc.

What do you think, is Quantun GIS a good place to start, or should I look for some other GIS?
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Re: Quantum GIS and cadastre

Ziegler Stefan
Scalix message content
Hi
there will be definitely better informed people about all the possibilites of QGIS and more profound answers. But as as surveyor I can give you the following answers: 1. - 4. Yes.

One big drawback for productive use in cadastral surveying is the lack of support of circular arcs which is essential in Switzerland. I don't know if it's necessary in Ukraine. The map composer is at the moment not state of the art but will be improved next year.

I heard there's a project of the worldbank which has something to do with open source cadastral surveying GIS. If you want I can ask for more information.

@Horst: Do you have more precise information about the map composer and/or circular arcs (perhaps the dude from Uster :))?

Merry Chrismas
Stefan

-----Ursprüngliche Nachricht-----
Von: Beowulf [mailto:[hidden email]]
Gesendet am: Sonntag, 23. Dezember 2007 11:51
An: [hidden email]
Betreff: [Qgis-user] Quantum GIS and cadastre

Hi! I'm fairly new to this, so this is probably a newbie question :)

I live and work in Ukraine. Our company works with land on a local scale.
That means that we do surveys of people's land plots (with a tacheometer)
and do all kinds of stuff with that information. First we need to convert
the field traverse into the coordinates of individual points. Then we need
to put those points on a map. Also, we need to supply these land plots with
a bunch of information (like who is the owner of the plot and what
limitations on the use of the land are in place and so on). And finally we
print reports like the cadastre plan. And create an exchange file (special
format) with all the data to upload it to the main cadastre base.

The way we do it now is REALLY ugly. It's done with a bunch of buggy, kludgy
assorted tools. I am trying to set this all straight, and here's my
question. Can QGIS be a good platform for this? Here are the requirements:

1. The GIS is open source, free.
2. It can associate data with objects on the map. The data is in a
relational DB and can be queried.
3. It can display vector data and raster data reasonably fast (not slower
than AutoCAD).
4. Plugins can be written for it, for instance a plugin to convert field
traverse report to coordinates, a plugin to conveniently fill all the
information for a land plot (a form), etc.

What do you think, is Quantun GIS a good place to start, or should I look
for some other GIS?
--
View this message in context: http://www.nabble.com/Quantum-GIS-and-cadastre-tp14477338p14477338.html
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Re: Quantum GIS and cadastre

Beowulf
I can tell you for sure that we don't use arcs in cadastre in this country. Only points, lines and polygons. In fact, I've seen several land plots which have circular fragments and they have been done as polygons.

And if you have info about a specialized GIS, please tell me about it!

Waiting for your soon reply!


Ziegler Stefan wrote
Hi there will be definitely better informed people about all the
possibilites of QGIS and  more profound answers. But as as surveyor I
can give you the following answers: 1. - 4. Yes.

One big drawback for productive use in cadastral surveying is the lack
of support of circular arcs which is essential in Switzerland. I don't
know if it's necessary in Ukraine. The map composer is at the moment not
state of the art but will be improved next year.

I heard there's a project of the worldbank which has something to do
with open source cadastral surveying GIS. If you want I can ask for more
information.
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Re: Quantum GIS and cadastre

Brent Wood
--- Beowulf <[hidden email]> wrote:

Note that QGIS has no internal support for a "native" datatype supporting arcs
or any other feature type. QGIS uses GDAL/OGR as a generic data accessor,
although I understand it has a custom PostGIS driver, instead of using the OGR
one. Therefore, to support curves, splines, etc, as geometry components, it is
first necessary to have these supported in data formats which are accessed by
QGIS. This is unlikely to happen for shapefiles or most other formats, but I
believe some progress is being made to support topological GIS features in
PostGIS, in which case assembling polygons (or line features) from constituent
linestrings & arcs may well become feasible in future.

However, you'll get more info about this from Postgis forums than QGIS. There
may also be something happening on the OGC front, as they wrote the Simple
Features Specification for storing geometries in relational databases

Cheers,

   Brent Wood


 

> I can tell you for sure that we don't use arcs in cadastre in this country.
> Only points, lines and polygons. In fact, I've seen several land plots which
> have circular fragments and they have been done as polygons.
>
> And if you have info about a specialized GIS, please tell me about it!
>
> Waiting for your soon reply!
>
>
>
> Ziegler Stefan wrote:
> >
> > Hi there will be definitely better informed people about all the
> > possibilites of QGIS and  more profound answers. But as as surveyor I
> > can give you the following answers: 1. - 4. Yes.
> >
> > One big drawback for productive use in cadastral surveying is the lack
> > of support of circular arcs which is essential in Switzerland. I don't
> > know if it's necessary in Ukraine. The map composer is at the moment not
> > state of the art but will be improved next year.
> >
> > I heard there's a project of the worldbank which has something to do
> > with open source cadastral surveying GIS. If you want I can ask for more
> > information.
> >
>
> --
> View this message in context:
> http://www.nabble.com/Quantum-GIS-and-cadastre-tp14477338p14481386.html
> Sent from the qgis-user mailing list archive at Nabble.com.
>
> _______________________________________________
> Qgis-user mailing list
> [hidden email]
> http://lists.qgis.org/cgi-bin/mailman/listinfo/qgis-user
>

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Re: Quantum GIS and cadastre

Beowulf
Brent Wood-2 wrote
Note that QGIS has no internal support for a "native" datatype supporting arcs
or any other feature type.
Like I mentioned before, I don't need arcs at all. In fact, it seems that PostGIS is a PERFECT place to store all my data. Now I'm getting to know QGIS better and better, and it looks like a good piece of software. At the moment I see that it is really lacking a good and powerful editor. For instance, more different snaps would be good, like in AutoCAD. So far, the editor is only good for low-precision tracing of raster maps. Maybe there's a plugin that would extend QGIS' editing capabilities?

Am I missing something here?

Konstantin.
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Re: Quantum GIS and cadastre

Hugentobler  Marco
Hi Konstantin,

There are more editing features in the editing development branch and it is
planned to merge them into trunk for version 0.9.2. The new features include
snap to vertex/to segment, different snapping distances for different layers,
topological editing, splitting of lines/polygons, moving features.

If you are curious to try theses features already now, you may check out the
branch using:

 svn co https://svn.qgis.org/repos/qgis/branches/advanced_editing_branch

cheers,
Marco

Am Samstag 29 Dezember 2007 11:11:07 schrieb Beowulf:

> Brent Wood-2 wrote:
> > Note that QGIS has no internal support for a "native" datatype supporting
> > arcs
> > or any other feature type.
>
> Like I mentioned before, I don't need arcs at all. In fact, it seems that
> PostGIS is a PERFECT place to store all my data. Now I'm getting to know
> QGIS better and better, and it looks like a good piece of software. At the
> moment I see that it is really lacking a good and powerful editor. For
> instance, more different snaps would be good, like in AutoCAD. So far, the
> editor is only good for low-precision tracing of raster maps. Maybe there's
> a plugin that would extend QGIS' editing capabilities?
>
> Am I missing something here?
>
> Konstantin.



--
Dr. Marco Hugentobler
Institute of Cartography
ETH Zurich
Technical Advisor QGIS Project Steering Committee
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Re: Quantum GIS and cadastre

Ziegler Stefan
In reply to this post by Beowulf
Scalix message content
Konstantin

No arcs? Lucky you! I found this: http://www.urigal.net/medias/files/gis-tools.tar.gz These are some python scripts for doing some surveying calculation like lat/lon -> UTM or polar-coords -> cartesian-coords. The guy's intention is to make a qgis plugin sometimes (as written in the readme). If you need to transform some local gps coords into a national reference frame or something similar you could probably make use of the qgis georefencer plugin (with some changes) which is able to make a helmert transformation. It would be nice if we have some cadastral surveying specific things in qgis.
I keep you informed about the worldbank project. Since we are on christmas holidays you have to be patient.

Stefan

-----Ursprüngliche Nachricht-----
Von: Beowulf [mailto:[hidden email]]
Gesendet am: Freitag, 28. Dezember 2007 22:52
An: [hidden email]
Betreff: Re: [Qgis-user] Quantum GIS and cadastre

I can tell you for sure that we don't use arcs in cadastre in this country.
Only points, lines and polygons. In fact, I've seen several land plots which
have circular fragments and they have been done as polygons.

And if you have info about a specialized GIS, please tell me about it!

Waiting for your soon reply!

Ziegler Stefan wrote:
>
> Hi there will be definitely better informed people about all the
> possibilites of QGIS and more profound answers. But as as surveyor I
> can give you the following answers: 1. - 4. Yes.
>
> One big drawback for productive use in cadastral surveying is the lack
> of support of circular arcs which is essential in Switzerland. I don't
> know if it's necessary in Ukraine. The map composer is at the moment not
> state of the art but will be improved next year.
>
> I heard there's a project of the worldbank which has something to do
> with open source cadastral surveying GIS. If you want I can ask for more
> information.
>

--
View this message in context: http://www.nabble.com/Quantum-GIS-and-cadastre-tp14477338p14481386.html
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Re: Quantum GIS and cadastre

Beowulf
In reply to this post by Hugentobler Marco
Marco Hugentobler-3 wrote
There are more editing features in the editing development branch and it is
planned to merge them into trunk for version 0.9.2. The new features include
snap to vertex/to segment, different snapping distances for different layers,
topological editing, splitting of lines/polygons, moving features.
That's great news! When is 0.9.2 due?
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Re: Quantum GIS and cadastre

Beowulf
In reply to this post by Ziegler Stefan
Thanks a lot! I'm getting acquainted with PostGIS and I think it's exactly what I need to store all the data. And with QGIS support for PostGIS layer it all works out just great. Just a few plugins to parse field traverses and a form to edit semantic data and we have a great cadastral surveying GIS. Right now I am working on a parser to read out national cadastral exchange format and put it into PostGIS.

Actually, most of ex-USSR is using old soviet coordinates CK-63. Since all our reference points are in these coordinates anyway, parsing a field traverse is no more than polar to cartesian conversion.


Konstantin.


Ziegler Stefan wrote
No arcs? Lucky you! I found this:
http://www.urigal.net/medias/files/gis-tools.tar.gz These are some
python scripts for doing some surveying calculation like lat/lon -> UTM
or  polar-coords -> cartesian-coords. The guy's intention is to make a
qgis plugin sometimes (as written in the readme). If you need to
transform  some local gps coords into a national reference frame or
something similar you could probably make use of the qgis georefencer
plugin (with some changes) which is able to make a helmert
transformation. It would be nice if we have some cadastral surveying
specific things in qgis.
I keep you informed about the worldbank project. Since we are on
christmas holidays you have to be patient.
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Re: Quantum GIS and cadastre

sebastian sauer-2
In reply to this post by Beowulf
Sat 29 Dec 2007 17:29, Beowulf wrote:
> Actually, most of ex-USSR is using old soviet coordinates CK-63.
or more widely known outside the .su domain as CS-63 .. comes in different
zones (obviously ;) [0]
datum should be the usual pulkovo 1942, hence the ellipsoid should be
krassowsky 1940

IIRC was quite hassle-free with proj.

[0] zone naming scheme is IIRC a cyrillic char which is followed by a int

> Since all
> our reference points are in these coordinates anyway, parsing a field
> traverse is no more than polar to cartesian conversion.
sure. as along as e.g. no WGS-84 coordinates, e.g. from a GPS survey are also
in use..

cheers,
s.
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Re: Quantum GIS and cadastre

Beowulf
Whoa, you seem to know a lot about this. I'm new to this but AFAIK the conversion keys between different systems are a soviet military secret :)

I am not sure what our zone is, but our coords are something like X=643400.88,Y=340232.37. BTW, does the rest of the world consider south-north axis as "Y" and west-east as "X", or is it just us?


sebastian sauer-2 wrote
or more widely known outside the .su domain as CS-63 .. comes in different
zones (obviously ;) [0]
datum should be the usual pulkovo 1942, hence the ellipsoid should be
krassowsky 1940
IIRC was quite hassle-free with proj.
[0] zone naming scheme is IIRC a cyrillic char which is followed by a int
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Re: Quantum GIS and cadastre

sebastian sauer-2
Sun 30 Dec 2007 00:20, Beowulf wrote:
> Whoa, you seem to know a lot about this.
i wish i did; yet all i know is that my knowledge here is almost zero.

> I'm new to this but AFAIK the
> conversion keys between different systems are a soviet military secret :)
frankly i don't know. in practice "official" helmert parameters are
either *very* hard to get or simply do not exist.

< but could try and contact http://roskart.gov.ru/ .->

i just checked .. http://www.epsg-registry.org/ knows the usual
generalites about СК-63 if you enter it "western style" as CS63.
but no helmert parameters of course.

and http://crs.bkg.bund.de/crs-eu/ knows actually astonishly little.

> I am not sure what our zone is, but our coords are something like
> X=643400.88,Y=340232.37. BTW, does the rest of the world consider
> south-north axis as "Y" and west-east as "X", or is it just us?
ah yes, right you are.. .. northing/easting is most often swapped in the
.su mapping.

maybe to make it a little less off-topic for the rest. AFAIK CS-63 was/is
the civilian / declassified mapping stuff.

much better, in some cases even of extremly high quality and covering
almost the full globe are the .su military maps.

nowadays high-quality, georeferenced scans of these are quite easy to
get..

http://www.poehali.org/en/
http://maps.vlasenko.net/ (.ua only)
http://maps.vlasenko.net/map-1k.html

map legend, symbology, background info..
http://www.lib.berkeley.edu/EART/pdf/soviet.pdf
http://www.sovietmaps.com/

cheers,
s.

ps: historic maps covering parts of .ua
http://lazarus.elte.hu/hun/digkonyv/topo/3felmeres.htm
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Re: Quantum GIS and cadastre

sebastian sauer-2
Sun 30 Dec 2007 16:33, sebastian sauer wrote:
> Sun 30 Dec 2007 00:20, Beowulf wrote:
> > I'm new to this but AFAIK the
> > conversion keys between different systems are a soviet military secret :)
> frankly i don't know. in practice "official" helmert parameters are
> either *very* hard to get or simply do not exist.
addendum: well i think i should be more precise here, so that i don't get
flamed :)

the helmert parameters obviously one can derive/fit him-/her-self given
enough ground control points (GCP)
..but getting "official data" of these points for the most parts of the
former .su area is somehow really hard in practice.

s.
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Re: Quantum GIS and cadastre

Beowulf
In reply to this post by sebastian sauer-2
sebastian sauer-2 wrote
ah yes, right you are.. .. northing/easting is most often swapped in the
.su mapping.
maybe to make it a little less off-topic for the rest. AFAIK CS-63 was/is
the civilian / declassified mapping stuff.
much better, in some cases even of extremly high quality and covering
almost the full globe are the .su military maps.
nowadays high-quality, georeferenced scans of these are quite easy to
get..
OMG! Thanks a million! The maps are great, I'll download them as soon as I can. Now as for the X and Y... So the rest of the world thinks Y is east-west? Then QGIS does that too and I need to adjust for that, right?
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Re: Quantum GIS and cadastre

sebastian sauer-2
Sun 30 Dec 2007 22:20, Beowulf wrote:
> can. Now as for the X and Y... So the rest of the world thinks Y is
> east-west? Then QGIS does that too and I need to adjust for that, right?
i'm not really familiar with qgis but proj has the -r && -s flags exactly
for that.

how to express the axis order in WKT i for myself, just dont know.
of course you could specifiy AXIS["x",NORTH], AXIS["y",EAST] but you never
know how this is interpreted by $YOUR_FAVOURITE_GIS_SOFTWARE

actually the .cz/.sk krovak specialists probably can answer your question
much better. AFAIK krovak also has the axis flipped and often also sign
inverted.

s.
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Re: Quantum GIS and cadastre

CraigLeat
sebastian sauer-2 wrote
Sun 30 Dec 2007 22:20, Beowulf wrote:
> can. Now as for the X and Y... So the rest of the world thinks Y is
> east-west?

actually the .cz/.sk krovak specialists probably can answer your question
much better. AFAIK krovak also has the axis flipped and often also sign
inverted.
In South Africa we use a South Oriented Transverse Mercator projection. X increases from north to south and Y increases from east to west. This is backward as far as (most) the rest of the world is concerned. Proj.4 does not support south oriented tmerc so when using qgis et al I need to change the signs of my coordinates. This is a real pain when moving back and forth between qgis et al and my proprietary Civil Design software which supports the South African datums.

Hoping for a project sometime that will fund the development of proj.4 to support south oriented tmerc ...  ;-)

Craig
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Re: Quantum GIS and cadastre

Magnus Homann
In reply to this post by Beowulf
Beowulf wrote:
> Whoa, you seem to know a lot about this. I'm new to this but AFAIK the
> conversion keys between different systems are a soviet military secret :)
>
> I am not sure what our zone is, but our coords are something like
> X=643400.88,Y=340232.37. BTW, does the rest of the world consider
> south-north axis as "Y" and west-east as "X", or is it just us?

Swedish RT90 and (Sweref99 TM?) has X north/south and Y east/west.
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Re: Quantum GIS and cadastre

David Fawcett
In reply to this post by CraigLeat
Have you tried editing your local proj.4 database to include the definition of your south oriented projection?  Is it an issue of the definition not being in the database, or that proj.4 can't handle the south orientation even with a valid projection definition? 

David.

On Jan 7, 2008 7:35 AM, Craig Leat <[hidden email]> wrote:


sebastian sauer-2 wrote:
>
> Sun 30 Dec 2007 22:20, Beowulf wrote:
>> can. Now as for the X and Y... So the rest of the world thinks Y is
>> east-west?
>
> actually the .cz/.sk krovak specialists probably can answer your question
> much better. AFAIK krovak also has the axis flipped and often also sign
> inverted.
>

In South Africa we use a South Oriented Transverse Mercator projection. X
increases from north to south and Y increases from east to west. This is
backward as far as (most) the rest of the world is concerned. Proj.4 does
not support south oriented tmerc so when using qgis et al I need to change
the signs of my coordinates. This is a real pain when moving back and forth
between qgis et al and my proprietary Civil Design software which supports
the South African datums.

Hoping for a project sometime that will fund the development of proj.4 to
support south oriented tmerc ...  ;-)

Craig
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Re: Quantum GIS and cadastre

CraigLeat
David Fawcett wrote:
Have you tried editing your local proj.4 database to include the definition of your south oriented projection?  Is it an issue of the definition not being in the database, or that proj.4 can't handle the south orientation even with a valid projection definition? 

David.

On Jan 7, 2008 7:35 AM, Craig Leat <[hidden email]> wrote:


sebastian sauer-2 wrote:
>
> Sun 30 Dec 2007 22:20, Beowulf wrote:
>> can. Now as for the X and Y... So the rest of the world thinks Y is
>> east-west?
>
> actually the .cz/.sk krovak specialists probably can answer your question
> much better. AFAIK krovak also has the axis flipped and often also sign
> inverted.
>

In South Africa we use a South Oriented Transverse Mercator projection. X
increases from north to south and Y increases from east to west. This is
backward as far as (most) the rest of the world is concerned. Proj.4 does
not support south oriented tmerc so when using qgis et al I need to change
the signs of my coordinates. This is a real pain when moving back and forth
between qgis et al and my proprietary Civil Design software which supports
the South African datums.

Hoping for a project sometime that will fund the development of proj.4 to
support south oriented tmerc ...  ;-)

Craig


Hi

The proj.4 projection definition parameters do not provide for specifying south oriented axes. The proj.4 options -s and -m mentioned earlier in this thread are used by the commandline programs (proj and invproj) and not the library. For gdal/ogr and hence qgis, grass and mapserver to support south oriented axes changes need to be made to the proj.4 library.

I find it interesting that this functionality appears to be required elsewhere in the world, besides my little country.

Craig

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Re: Quantum GIS and cadastre

CraigLeat
In reply to this post by Beowulf
Aaah! Caught by the html devil again. Sorry for the double post, but
this version should at least be readable.

Craig


David Fawcett wrote:

> Have you tried editing your local proj.4 database to include the
> definition of your south oriented projection?  Is it an issue of the
> definition not being in the database, or that proj.4 can't handle the
> south orientation even with a valid projection definition?
>
> David.
>
> On Jan 7, 2008 7:35 AM, Craig Leat <[hidden email]
> <mailto:[hidden email]>> wrote:
>
>
>
>     sebastian sauer-2 wrote:
>     >
>     > Sun 30 Dec 2007 22:20, Beowulf wrote:
>     >> can. Now as for the X and Y... So the rest of the world thinks Y is
>     >> east-west?
>     >
>     > actually the .cz/.sk krovak specialists probably can answer your
>     question
>     > much better. AFAIK krovak also has the axis flipped and often
>     also sign
>     > inverted.
>     >
>
>     In South Africa we use a South Oriented Transverse Mercator
>     projection. X
>     increases from north to south and Y increases from east to west.
>     This is
>     backward as far as (most) the rest of the world is concerned.
>     Proj.4 does
>     not support south oriented tmerc so when using qgis et al I need
>     to change
>     the signs of my coordinates. This is a real pain when moving back
>     and forth
>     between qgis et al and my proprietary Civil Design software which
>     supports
>     the South African datums.
>
>     Hoping for a project sometime that will fund the development of
>     proj.4 to
>     support south oriented tmerc ...  ;-)
>
>     Craig
>
>

Hi

The proj.4 projection definition parameters do not provide for
specifying south oriented axes. The proj.4 options -s and -m mentioned
earlier in this thread are used by the commandline programs (proj and
invproj) and not the library. For gdal/ogr and hence qgis, grass and
mapserver to support south oriented axes changes need to be made to the
proj.4 library.

I find it interesting that this functionality appears to be required
elsewhere in the world, besides my little country.

Craig
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