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I have dug up some old code I wrote 6 years ago that was doing the conversion from Lat Lon coordinates to UTM.

I have tried to run it today and the code returns NaN values. I suspect there has been some significant changes with GDAL. I am using GDAL 3.0 on Arch Linux.

Function latlon2utm takes X1, Y1 lat/lon coordinates and returns UTM coordinates X2, Y2

#include "ogr_api.h"
#include "ogr_srs_api.h"

void LatLon2UTM(double *X1, double *Y1, double *X2, double *Y2)
  {
  int zone;
  int err;

  printf("%f %f\n", *X1, *Y1);
  OGRGeometryH pt1;
  OGRSpatialReferenceH SREF;
  OGRSpatialReferenceH UTM;

  SREF = OSRNewSpatialReference(NULL);
  OSRImportFromEPSG(SREF, 4326);

  zone = (int)(((*X1 + 180.0) / 6.0) + 1.0);
  UTM = OSRNewSpatialReference(NULL);
  if(*Y1 < 0) OSRSetUTM(UTM,zone,FALSE);
  if(*Y1 > 0) OSRSetUTM(UTM,zone,TRUE);

  pt1 = OGR_G_CreateGeometry(wkbPoint);

  //printf("%f %f", *X1, *X2);
  OGR_G_SetPoint_2D(pt1, 0, *X1, *Y1);

  OGR_G_AssignSpatialReference(pt1, SREF);

  // Convert to UTM
  err = OGR_G_TransformTo(pt1,UTM);
  printf("%d", err);

  *X2 = OGR_G_GetX(pt1, 0);
  *Y2 = OGR_G_GetY(pt1, 0);
  printf("%f %f\n", *X2, *Y2);
  }

Is There anyone that could give me the proper way to do that?

  • 1
    Perhaps you should try #define USE_DEPRECATED_SRS_WKT_WGS84 before including ogr_srs_api.h that I found from the migration guide github.com/OSGeo/gdal/blob/release/3.0/gdal/MIGRATION_GUIDE.TXT. – user30184 Sep 9 at 6:28
  • You could try setting UTM using the EPSG code, it's 32700 + zone for southern hemisphere and 32600 + zone for northern hemisphere instead of using OSRSetUTM. – Michael Stimson Sep 9 at 7:06
  • Thanks! I am going to try that – rbeucher Sep 11 at 1:48
  • No luck. Anyone with a simple C-API example to do that? – rbeucher Sep 11 at 11:47

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