Hi Jay,
In "standalone" ncWMS you can now create your own epsg.properties file to add
your own projections to those in the Geotoolkit database. I can't remember if
this capability has also been migrated to THREDDS - Ethan may be able to
advise. Basically, if there is a file called
org/geotoolkit/referencing/factory/epsg/epsg.properties on your classpath,
ncWMS will pick this up and look for CRS definitions (in WKT) therein.
You could try creating such a file if it doesn't exist and adding your
projection. Reboot the server, then test with a GetMap operation (it won't show
up in GetCapabilities).
Cheers,
Jon
----------------------------------------------------------------------
Message: 1
Date: Fri, 12 Jul 2013 17:16:41 -0700
From: Jay Alder <jay.alder@xxxxxxxxxxxxxxxxxxx>
To: Ethan Davis <edavis@xxxxxxxxxxxxxxxx>
Cc: thredds@xxxxxxxxxxxxxxxx
Subject: Re: [thredds] Albers or LCC supported as a WMS projection on
the TDS?
Message-ID: <51E09C69.4030005@xxxxxxxxxxxxxxxxxxx>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Hi Ethan.
I'm having a little trouble following along in this old thread. I'm trying to
see if it is possible to use a North America variant of Albers in TDS 4.3. It
doesn't seem like I can use the many projections listed in epsg.properties like
I could in TDS 4.2, unless I'm not building the url correctly. I would like to
use 42303, which is listed in epsg.properties, but it doesn't seem to be
working for me. If I set the
version=1.1.1 the browser says file not found (rather than a TDS xml error). If
I set the version to 1.3.0 I get an xml error saying 'The CRS
EPSG:42303 is not supported by this server'.
Is there a way to get this projection working in TDS? Here is the entry in
epsg.properties.
42303=PROJCS["NAD83 / Albers
NorthAm",GEOGCS["NAD83",DATUM["North_American_Datum_1983",SPHEROID["GRS_1980",6378137,298.257222101],TOWGS84[0,0,0]],PRIMEM["Greenwich",0],UNIT["Decimal_Degree",0.0174532925199433]],PROJECTION["Albers_conic_equal_area"],PARAMETER["central_meridian",-96.0],PARAMETER["latitude_of_origin",23],PARAMETER["standard_parallel_1",29.5],PARAMETER["standard_parallel_2",45.5],PARAMETER["false_easting",0],PARAMETER["false_northing",0],UNIT["Meter",1],AUTHORITY["EPSG","42303"]]
Thanks
On 10/17/2012 03:13 PM, Ethan Davis wrote:
> Ack! Sorry about that. I'm always stumbling over the various types of
> EPSG codes.
>
> Yes, the Albers and LLC EPSG codes you gave are for particular types
> of projections, in EPSG aka "coordinate operations methods". From
> which can be built particular "coordinate operations" (which I assume
> have specific parameter values though I'm having trouble finding them
> in the database). And from there, the coordinate reference systems.
>
> My understanding is that the epsg.properties file (in epsg-wkt.jar) is
> used in TDS 4.2 but not in TDS 4.3 (GeoToolkit 3.04 vs 3.17). The one
> in TDS 4.3 should be newer and a more complete list of EPSG CRSs. So,
> once you decide which EPSG CRS codes you want to use, I suspect
> requests for them will work without changes in TDS 4.3 but may need
> the additions Marcos mentions below. On the other hand, it appears
> that the epsg.properties file in TDS 4.2 already contains a WKT for
> CRS 2205 and I suspect it contains other Albers and LLC based CRSs as well.
>
> If that all works, another fun part is figuring out for each CRS the
> valid values of the bounding box corners.
>
> Ethan
>
>
> On 10/17/2012 3:24 PM, Marcos Hermida wrote:
>> Hi Rich,
>>
>> to define either a Lambert Conformal Projection or Albers Equals Area
>> you need to provide a set of parameters (standards parallels, central
>> meridians, northing, easting...) so there are whole family of LCC and
>> Albers projections that you can use. Here you can see some well
>> defined ones, with their EPSG codes:
>> Albers:
>> http://spatialreference.org/ref/epsg/?search=Albers+Equal+Area&srtext
>> =Search
>>
>> LCC:
>> http://spatialreference.org/ref/epsg/?search=Lambert+Conic+Conformal+
>> 2SP&srtext=Search
>>
>>
>> If you want to use some of them all you have to do is add the OGC WKT
>> to the epsg database that is used by ncWMS/THREDDS. That database is
>> the epsg.properties file that lives in the epsg-wkt.jar and those are
>> the actual projections supported by the ncWMS/THREDDS.
>> So, for instance, if you want to add the Lambert Conic Conformal 2SP:
>> NAD83 / Massachusetts Island
>> (http://spatialreference.org/ref/epsg/2250/) you need to add to the
>> epsg.properties this OGC WKT:
>> http://spatialreference.org/ref/epsg/2250/ogcwkt/ with its EPSG code.
>> It would look like something like this:
>>
>> 2250=PROJCS["NAD83 / Massachusetts Island
>> (ftUS)",GEOGCS["NAD83",DATUM["North_American_Datum_1983",SPHEROID["GR
>> S
>> 1980",6378137,298.257222101,AUTHORITY["EPSG","7019"]],AUTHORITY["EPSG
>> ","6269"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT["degre
>> e",0.01745329251994328,AUTHORITY["EPSG","9122"]],AUTHORITY["EPSG","42
>> 69"]],UNIT["US
>> survey
>> foot",0.3048006096012192,AUTHORITY["EPSG","9003"]],PROJECTION["Lamber
>> t_Conformal_Conic_2SP"],PARAMETER["standard_parallel_1",41.4833333333
>> 3333],PARAMETER["standard_parallel_2",41.28333333333333],PARAMETER["l
>> atitude_of_origin",41],PARAMETER["central_meridian",-70.5],PARAMETER[
>> "false_easting",1640416.667],PARAMETER["false_northing",0],AUTHORITY[
>> "EPSG","2250"],AXIS["X",EAST],AXIS["Y",NORTH]]
>>
>>
>>
>> Cheers!
>>
>>
>> On 10/17/2012 11:53 AM, Rich Signell wrote:
>>> Ethan,
>>>
>>> That's great that Albers, LCC and others should work with TDS 4.3 WMS.
>>>
>>> That means it should work on:
>>> http://motherlode.ucar.edu:9080/thredds
>>> which is at TDS 4.3.15.
>>>
>>> So on that server, I can get this WMS request to work using EPSG:4326:
>>>
>>> http://motherlode.ucar.edu:9080/thredds/wms/grib/NCEP/NAM/CONUS_12km
>>> /files/NAM_CONUS_12km_20121017_1200.grib2?LAYERS=Temperature_height_
>>> above_ground&ELEVATION=2&TIME=2012-10-17T12%3A00%3A00.000Z&TRANSPARE
>>> NT=true&STYLES=boxfill%2Frainbow&CRS=EPSG%3A4326&COLORSCALERANGE=263
>>> .7%2C302.6&NUMCOLORBANDS=20&LOGSCALE=false&SERVICE=WMS&VERSION=1.1.1
>>> &REQUEST=GetMap&FORMAT=image%2Fpng&SRS=EPSG%3A4326&BBOX=-128.1615439
>>> 5928,13.676912081443,-76.323087918557,65.515368122164&WIDTH=256&HEIG
>>> HT=256
>>>
>>>
>>> But I can't get anything else to work.
>>>
>>> Can you provide a modified version of the above request that works
>>> for Albers (EPSG:9822) or LCC (EPSG:9802)
>>>
>>> -Rich
>>>
>>> On Wed, Oct 17, 2012 at 11:55 AM, Ethan Davis
>>> <edavis@xxxxxxxxxxxxxxxx> wrote:
>>>> Hi Rich,
>>>>
>>>> Even if a CRS is not listed, both ncWMS and TDS WMS can handle
>>>> requests for any CRS supported by the underlying GeoToolkit
>>>> library. The CRS database in TDS 4.2 does not contain EPSG CRS 9822
>>>> or 9802. However, they should both be available in TDS 4.3. So, if
>>>> you are trying this on a TDS 4.3, you can just give it a try.
>>>>
>>>> As for the WMS GetCapabilities CRS list, it is currently not user
>>>> configurable. For TDS 4.3 it would simply be a matter of a minor
>>>> code change (adding the two EPSG numbers to a list) and then
>>>> rebuilding. It is a bit more work in TDS 4.2, but not much harder,
>>>> along with adding the EPSG number to a list, we would need a WKT
>>>> for each of the new projections. (The CRS WKT needs to be in a form
>>>> the GeoToolkit can
>>>> read.)
>>>>
>>>> We've kept the list to a minimum because in earlier versions we
>>>> listed all available projections and the list got quite large.
>>>>
>>>> Are you using TDS 4.3? Do you need these CRS to be in the list or
>>>> is being able to request them enough?
>>>>
>>>> Cheers,
>>>>
>>>> Ethan
>>>>
>>>> On 10/17/2012 8:17 AM, Rich Signell wrote:
>>>>> TDS folks,
>>>>>
>>>>> What would it take to get Albers or LCC supported as a projection
>>>>> on the TDS WMS?
>>>>>
>>>>> According to the WMS getCapabilities (for example:
>>>>> http://motherlode.ucar.edu/thredds/wms/fmrc/NCEP/GFS/CONUS_191km/N
>>>>> CEP-GFS-CONUS_191km_best.ncd?service=WMS&version=1.3.0&request=Get
>>>>> Capabilities
>>>>>
>>>>>
>>>>> the supported projections are:
>>>>> <Title>Motherlode TDS</Title>
>>>>> <CRS>EPSG:4326</CRS>
>>>>> <CRS>CRS:84</CRS>
>>>>> <CRS>EPSG:41001</CRS>
>>>>> <CRS>EPSG:3857</CRS>
>>>>> <CRS>EPSG:27700</CRS>
>>>>> <CRS>EPSG:3408</CRS>
>>>>> <CRS>EPSG:3409</CRS>
>>>>> <CRS>EPSG:32661</CRS>
>>>>> <CRS>EPSG:32761</CRS>
>>>>>
>>>>> Okay, so we don't see Albers Equal Area (EPSG:9822) or Lambert
>>>>> Conformal Conic 2SP (EPSG:9802) on the list.
>>>>>
>>>>> But TDS WMS is based on ncWMS, and on the ncWMS FAQ at:
>>>>>
>>>>> http://www.resc.rdg.ac.uk/trac/ncWMS/wiki/FrequentlyAskedQuestions
>>>>>
>>>>> it says that ncWMS "can produce images in any projection that is
>>>>> supported by the GeoTools library".
>>>>>
>>>>> And it appears that GeoTools can support both Albers and LCC:
>>>>>
>>>>> http://docs.geotools.org/latest/javadocs/org/geotools/referencing/
>>>>> operation/projection/package-summary.html
>>>>>
>>>>>
>>>>> So would it be straightforward (or perhaps even easy) to allow the
>>>>> TDS WMS to support these?
>>>>>
>>>>> Thanks,
>>>>> Rich
>>>>>
>>>> --
>>>> Ethan Davis UCAR Unidata Program
>>>> edavis@xxxxxxxxxxxxxxxx http://www.unidata.ucar.edu
>>>>
>>>> _______________________________________________
>>>> thredds mailing list
>>>> thredds@xxxxxxxxxxxxxxxx
>>>> For list information or to unsubscribe, visit:
>>>> http://www.unidata.ucar.edu/mailing_lists/
>>>
--
Jay Alder
US Geological Survey
Oregon State University
104 COAS Admin Building
Office Burt Hall 166
http://ceoas.oregonstate.edu/profile/alder/
End of thredds Digest, Vol 54, Issue 4
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