Re: [gdal-dev] Unable to obtain EPSG from OGRSpatialReference

2017-06-07 Thread Mike K
Nik Sands, thank you, you nailed it. That was my problem: the UTM coordinate system I was expecting is projected, so I needed to use those functions you listed with the "PROJCS" key to get the proper EPSG code. Once I parsed out the code, I get 32617 as expected. Thank you all! -- View th

Re: [gdal-dev] Unable to obtain EPSG from OGRSpatialReference

2017-06-07 Thread Ian Lilly
Andre, My reading of his description is that he's using projected coords (i.e. metres) so for UTM 17N isn't that this - https://epsg.io/32617? EPSG4326 is WGS84, geographic (lat/lon) which defines the spheroid used in UTM. I'm not a C++ programmer nor have I read the docs for the GDAL API - perhap

Re: [gdal-dev] Unable to obtain EPSG from OGRSpatialReference

2017-06-07 Thread Nik
It seems like you may be trying to get the EPSG code for the projected SRS but you are using a call that retrieves the geographic SRS. If this is the case then you might want to try using both of: OGRSpatialReference::GetAuthorityName OGRSpatialReference::GetAuthorityCode These are not guara

Re: [gdal-dev] Unable to obtain EPSG from OGRSpatialReference

2017-06-06 Thread Andre Joost
Am 07.06.2017 um 02:35 schrieb Mike K: Hello, I have a situation in which I would like to load up a set of polygons, and determine what EPSG code they are using. I am testing with a simple square polygon in upstate New York using the UTM projection, saved into a Shapefile . I am able to create

[gdal-dev] Unable to obtain EPSG from OGRSpatialReference

2017-06-06 Thread Mike K
Hello, I have a situation in which I would like to load up a set of polygons, and determine what EPSG code they are using. I am testing with a simple square polygon in upstate New York using the UTM projection, saved into a Shapefile . I am able to create my dataset, layer, and read the geometry