[gdal-dev] Setting up a StatePlane Coordinate system

[Martin Chapman]

Christiaan,

 

Looks to me like two issues:

 

1.        Try using this coordinate system def for Alabama East:

 

PROJCS["NAD_1983_StatePlane_Alabama_East_FIPS_0101",GEOGCS["GCS_North_Americ
an_1983",DATUM["D_North_American_1983",SPHEROID["GRS_1980",6378137,298.25722
2101]],PRIMEM["Greenwich",0],UNIT["Degree",0.0174532925199432955]],PROJECTIO
N["Transverse_Mercator"],PARAMETER["False_Easting",200000],PARAMETER["False_
Northing",0],PARAMETER["Central_Meridian",-85.83333333333333],PARAMETER["Sca
le_Factor",0.99996],PARAMETER["Latitude_Of_Origin",30.5],UNIT["Meter",1]]

 

2.       Make sure the proj.dll is able to find the NAD files it depends on
for the transformation that are identified by an environment variable called
PROJ_LIB and the value should be something like c:\proj\nad.  If you don't
have the NAD files you can download them from www.proj4.org.  You can set
this environment variable at run time like so:

 

CPLSetConfigOption("PROJ_LIB", "c:\\proj\\nad");

 

Or you can set it in My Computer settings through the environment variables
dialog manually.

 

Give that a try and let me know how it went.

 

Best regards,

 

Martin Chapman

Chief Software Architect

Fortified Datacom Inc.

http://www.fortifieddatacom.com

mchapman at fortifieddatacom.com

303-324-1065

 

From: Christiaan Janssen [mailto:cjanssen at iavo-rs.com] 
Sent: Friday, December 28, 2007 1:06 PM
To: Martin Chapman
Subject: RE: [gdal-dev] Setting up a StatePlane Coordinate system

 

I'm trying to generate a Coordinate Transformation from NAD83 State Plane
Zone 101 (Alabama East) to WGS84 LatLon. Here are the Well Known Texts for
the source and destination:

Source: "LOCAL_CS["State Plane Zone 101 / NAD83",UNIT["Meter",1]]"

Destination: "GEOGCS["WGS 84",DATUM["WGS_1984",SPHEROID["WGS
84",6378137,298.257223563,AUTHORITY["EPSG","7030"]],TOWGS84[0,0,0,0,0,0,0],A
UTHORITY["EPSG","6326"]],PRIMEM["Greenwich",0,AUTHORITY["EPSG","8901"]],UNIT
["degree",0.0174532925199433,AUTHORITY["EPSG","9108"]],AXIS["Lat",NORTH],AXI
S["Long",EAST],AUTHORITY["EPSG","4326"]]"

 

I've been successful with UTM<->LatLon but not with the StatePlane based
transformations. And as a side not here's the error message from
CPLGetLastErrorMsg(): 

"No PROJ.4 translation for source SRS, coordinate
transformation initialization has failed."

 

Thanks,

Christiaan

 

  _____  

From: Martin Chapman [mailto:mchapman at texelinc.com] 
Sent: Friday, December 28, 2007 2:56 PM
To: 'Christiaan Janssen';gdal-dev at lists.osgeo.org
Subject: RE: [gdal-dev] Setting up a StatePlane Coordinate system

Christiaan,

 

Can you send me your projection string and I will validate the projection is
correct and then I will send back the code I used to do it.

 

Martin Chapman

Chief Software Architect

Fortified Datacom Inc.

http://www.fortifieddatacom.com

mchapman at fortifieddatacom.com

303-324-1065

 

From: gdal-dev-bounces at lists.osgeo.org
[mailto:gdal-dev-bounces at lists.osgeo.org] On Behalf Of Christiaan Janssen
Sent: Friday, December 28, 2007 12:32 PM
To: gdal-dev at lists.osgeo.org
Subject: [gdal-dev] Setting up a StatePlane Coordinate system

 

Could someone point me to (or provide me) a code snippet that shows how one
would go about setting up a State Plane zone based OGR Spatial Reference
object. Every attempt I've made has resulted in a SRS object that when used
with OGRCreateCoordinateTransformation() function always results in a
failure because there is no conversion from it. Thanks

 

Christiaan

 

 

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