CPLErr GXFDataset::GetGeoTransform( double * padfTransform )
{
CPLErr eErr;
double dfXOrigin, dfYOrigin, dfXSize, dfYSize, dfRotation;
eErr = GXFGetPosition( hGXF, &dfXOrigin, &dfYOrigin,
&dfXSize, &dfYSize, &dfRotation );
if( eErr != CE_None )
return eErr;
// Transform to radians.
dfRotation = (dfRotation / 360.0) * 2 * M_PI;
padfTransform[1] = dfXSize * cos(dfRotation);
padfTransform[2] = dfYSize * sin(dfRotation);
padfTransform[4] = dfXSize * sin(dfRotation);
padfTransform[5] = -1 * dfYSize * cos(dfRotation);
// take into account that GXF is point or center of pixel oriented.
padfTransform[0] = dfXOrigin - 0.5*padfTransform[1] - 0.5*padfTransform[2];
padfTransform[3] = dfYOrigin - 0.5*padfTransform[4] - 0.5*padfTransform[5];
return CE_None;
}
CPLErr GXFGetPROJ4Position( GXFHandle hGXF,
double * pdfXOrigin, double * pdfYOrigin,
double * pdfXPixelSize, double * pdfYPixelSize,
double * pdfRotation )
{
GXFInfo_t *psGXF = (GXFInfo_t *) hGXF;
char *pszProj;
/* -------------------------------------------------------------------- */
/* Get the raw position. */
/* -------------------------------------------------------------------- */
if( GXFGetPosition( hGXF,
pdfXOrigin, pdfYOrigin,
pdfXPixelSize, pdfYPixelSize,
pdfRotation ) == CE_Failure )
return( CE_Failure );
/* -------------------------------------------------------------------- */
/* Do we know the units in PROJ.4? Get the PROJ.4 string, and */
/* check for a +units definition. */
/* -------------------------------------------------------------------- */
pszProj = GXFGetMapProjectionAsPROJ4( hGXF );
if( strstr(pszProj,"+unit") == NULL && psGXF->pszUnitName != NULL )
{
if( pdfXOrigin != NULL )
*pdfXOrigin *= psGXF->dfUnitToMeter;
if( pdfYOrigin != NULL )
*pdfYOrigin *= psGXF->dfUnitToMeter;
if( pdfXPixelSize != NULL )
*pdfXPixelSize *= psGXF->dfUnitToMeter;
if( pdfYPixelSize != NULL )
*pdfYPixelSize *= psGXF->dfUnitToMeter;
}
CPLFree( pszProj );
return( CE_None );
}
