Hi, i'm reading a lot of sources from internet trying to explain how to make this transformation from coordintates as: V_LATITUDE = '9,54153844'; V_LONGITUDE = '39,44322841';
Into UTM values. We have a tiff map with a tfw file as follows: 50.0000000000 0.0000000000 0.0000000000 -50.0000000000 706876.2384142603 5976388.9235886401 As far as i read online, I've to use two OGRSpatialReference <http://www.gdal.org/classOGRSpatialReference.html> using one as the "destination" format and the second one as source format. But I don't understand how to set up the "origin" reference to accept latitude and longitude. >From OGR tutorial i see this snippet: OGRSpatialReference <http://www.gdal.org/classOGRSpatialReference.html> oUTM, *poLatLong; OGRCoordinateTransformation <http://www.gdal.org/classOGRCoordinateTransformation.html> *poTransform; oUTM.SetProjCS <http://www.gdal.org/classOGRSpatialReference.html#a208118581246feb29646acf2ea5d4237>("UTM 17 / WGS84"); oUTM.SetWellKnownGeogCS <http://www.gdal.org/classOGRSpatialReference.html#a096b8dde4fd2eb475acd376060940b02>( "WGS84" ); oUTM.SetUTM <http://www.gdal.org/classOGRSpatialReference.html#a0c4f6fcab663c9eb6d465787cad3833c>( 17 ); poLatLong = oUTM.CloneGeogCS <http://www.gdal.org/classOGRSpatialReference.html#a0c1e2b108255487f91ae448f5c11f67c>(); poTransform = OGRCreateCoordinateTransformation <http://www.gdal.org/ogr__spatialref_8h.html#aae11bd08e45cdb2e71e1d9c31f1e550f>( &oUTM, poLatLong ); if( poTransform == NULL ) { ... } ... if( !poTransform->Transform <http://www.gdal.org/classOGRCoordinateTransformation.html#abf141396940b4f7b1f8118ea025d569b>( nPoints, x, y, z ) ) ... I know how to obtain UTM zone (as floor[(longitude+180)/6]+1) but i'm not understanding if the call to Transform will take my longitude/latitude values or if i'll obtain a "complete" transformation from a reference system to another. The target is to access a GDALRasterBand and obtain a pixel value starting with returned coordinates. Thanks and regards, Pierpaolo
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