QList< QList< int > > QgsCoordinateTransform::datumTransformations( const QgsCoordinateReferenceSystem& srcCRS, const QgsCoordinateReferenceSystem& destCRS )
{
QList< QList< int > > transformations;
QString srcGeoId = srcCRS.geographicCRSAuthId();
QString destGeoId = destCRS.geographicCRSAuthId();
if ( srcGeoId.isEmpty() || destGeoId.isEmpty() )
{
return transformations;
}
QStringList srcSplit = srcGeoId.split( ":" );
QStringList destSplit = destGeoId.split( ":" );
if ( srcSplit.size() < 2 || destSplit.size() < 2 )
{
return transformations;
}
int srcAuthCode = srcSplit.at( 1 ).toInt();
int destAuthCode = destSplit.at( 1 ).toInt();
if ( srcAuthCode == destAuthCode )
{
return transformations; //crs have the same datum
}
QList<int> directTransforms;
searchDatumTransform( QString( "SELECT coord_op_code FROM tbl_datum_transform WHERE source_crs_code = %1 AND target_crs_code = %2" ).arg( srcAuthCode ).arg( destAuthCode ),
directTransforms );
QList<int> srcToWgs84;
searchDatumTransform( QString( "SELECT coord_op_code FROM tbl_datum_transform WHERE ( source_crs_code = %1 AND target_crs_code = %2 ) OR ( source_crs_code = %2 AND target_crs_code = %1 )" ).arg( srcAuthCode ).arg( 4326 ),
srcToWgs84 );
QList<int> destToWgs84;
searchDatumTransform( QString( "SELECT coord_op_code FROM tbl_datum_transform WHERE ( source_crs_code = %1 AND target_crs_code = %2 ) OR ( source_crs_code = %2 AND target_crs_code = %1 )" ).arg( destAuthCode ).arg( 4326 ),
destToWgs84 );
//add direct datum transformations
QList<int>::const_iterator directIt = directTransforms.constBegin();
for ( ; directIt != directTransforms.constEnd(); ++directIt )
{
transformations.push_back( QList<int>() << *directIt << -1 );
}
QList<int>::const_iterator srcWgsIt = srcToWgs84.constBegin();
for ( ; srcWgsIt != srcToWgs84.constEnd(); ++srcWgsIt )
{
QList<int>::const_iterator dstWgsIt = destToWgs84.constBegin();
for ( ; dstWgsIt != destToWgs84.constEnd(); ++dstWgsIt )
{
transformations.push_back( QList<int>() << *srcWgsIt << *dstWgsIt );
}
}
return transformations;
}
QList< QList< int > > QgsCoordinateTransform::datumTransformations( const QgsCoordinateReferenceSystem& srcCRS, const QgsCoordinateReferenceSystem& destCRS )
{
QList< QList< int > > transformations;
QString srcGeoId = srcCRS.geographicCRSAuthId();
QString destGeoId = destCRS.geographicCRSAuthId();
if ( srcGeoId.isEmpty() || destGeoId.isEmpty() )
{
return transformations;
}
QStringList srcSplit = srcGeoId.split( ":" );
QStringList destSplit = destGeoId.split( ":" );
if ( srcSplit.size() < 2 || destSplit.size() < 2 )
{
return transformations;
}
int srcAuthCode = srcSplit.at( 1 ).toInt();
int destAuthCode = destSplit.at( 1 ).toInt();
if ( srcAuthCode == destAuthCode || srcAuthCode == 0 || destAuthCode == 0)
{
return transformations; //crs have the same datum or no datum
}
QList<int> directTransforms;
searchDatumTransform( QString( "SELECT coord_op_code FROM tbl_datum_transform WHERE source_crs_code=%1 AND target_crs_code=%2" ).arg( srcAuthCode ).arg( destAuthCode ),
directTransforms );
QList<int> reverseDirectTransforms;
searchDatumTransform( QString( "SELECT coord_op_code FROM tbl_datum_transform WHERE source_crs_code = %1 AND target_crs_code=%2" ).arg( destAuthCode ).arg( srcAuthCode ),
reverseDirectTransforms );
//concatenated tranforms
QList< QList< int > > concatenatedTransforms;
searchDatumTransform2( QString( "SELECT src.coord_op_code, dest.coord_op_code FROM ") +
QString( "(SELECT coord_op_code, target_crs_code FROM tbl_datum_transform WHERE source_crs_code=%1) as src " ).arg( srcAuthCode ) +
QString( "INNER JOIN ") +
QString( "(SELECT coord_op_code, target_crs_code FROM tbl_datum_transform WHERE source_crs_code=%2) as dest " ).arg( destAuthCode ) +
QString( "ON src.target_crs_code=dest.target_crs_code ;" ),
concatenatedTransforms );
//add direct datum transformations
QList<int>::const_iterator directIt = directTransforms.constBegin();
for ( ; directIt != directTransforms.constEnd(); ++directIt )
{
transformations.push_back( QList<int>() << *directIt << -1 );
}
//add direct datum transformations
directIt = reverseDirectTransforms.constBegin();
for ( ; directIt != reverseDirectTransforms.constEnd(); ++directIt )
{
transformations.push_back( QList<int>() << -1 << *directIt );
}
//append concatenated datum transformations
transformations.append( concatenatedTransforms );
return transformations;
}