NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
Current content can be found at unidata.ucar.edu.
To learn about what's going on, see About the Archive Site.
NOTICE: This version of the NSF Unidata web site (archive.unidata.ucar.edu) is no longer being updated.
Current content can be found at unidata.ucar.edu.
To learn about what's going on, see About the Archive Site.
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
**************************************
thredds archives: