//*************************************************************************************************
//! Returns a projection corresponding to the group (e.g., "EPSG") and PCS code provided,
//! or NULL if no entry found.
//*************************************************************************************************
ossimProjection* ossimEpsgProjectionDatabase::findProjection(ossim_uint32 epsg_code) const
{
ossimMapProjection* proj = 0;
// Quick check for bogus EPSG:
if ((epsg_code == 0) || (epsg_code == 32767))
return 0;
// Check for Google projection:
else if (epsg_code == 900913)
{
const ossimDatum* datum = ossimDatumFactory::instance()->create(ossimString("6055"));
ossimMercatorProjection* merc_proj = new ossimMercatorProjection();
ossimGpt origin(0.0,0.0,0.0, datum);
merc_proj->setFalseEasting(0.0);
merc_proj->setFalseNorthing(0.0);
merc_proj->setOrigin(origin); // Also sets the projections datum to the origin's datum
merc_proj->update();
merc_proj->setPcsCode(900913);
proj = merc_proj;
}
else
{
// Search database for entry:
std::multimap<ossim_uint32, ossimRefPtr<ProjDbRecord> >::iterator db_iter =
m_projDatabase.find(epsg_code);
if (db_iter != m_projDatabase.end())
{
// See if a projection has already been created for this entry:
ProjDbRecord* db_record = db_iter->second.get();
if (db_record->proj.valid())
proj = (ossimMapProjection*) db_record->proj->dup();
else
{
// Try decoding the EPSG code before accessing DB:
proj = createProjFromUtmCode(epsg_code);
if (proj)
{
db_record->proj = proj;
db_record->datumValid = true;
}
else if (db_iter->second->csvFormat == FORMAT_A)
proj = createProjFromFormatARecord(db_record);
else if (db_iter->second->csvFormat == FORMAT_B)
proj = createProjFromFormatBRecord(db_record);
if (proj)
{
// To save allocated memory, get rid of the original CSV entry since a real
// projection is now represented in the database:
db_record->csvRecord.clear();
db_record->csvFormat = NOT_ASSIGNED;
}
}
}
}
return proj;
}
//*************************************************************************************************
//! This method is invoked to parse the Db record and produce a projection (or NULL if spec invalid)
//
// LIMITATION: Currently not parsing the datum info from the EPSG database file due to disconnect
// with current ossimDatumFactory. Setting to default WGS84 with warning message.
//*************************************************************************************************
ossimMapProjection*
ossimEpsgProjectionDatabase::createProjFromFormatARecord(const DbEntry& record,
bool& datum_valid) const
{
// Establish EPSG code and test for UTM (full projection is implied in the code itself -- no
// accessing the database). Until the database is solidified, it is probably better to do
// it this way:
datum_valid = true;
ossim_uint32 pcs_code = record[A_CODE].toUInt32();
ossimMapProjection* proj = createProjFromUtmCode(pcs_code);
if (proj)
return proj;
// Establish the units in which the easting/northing is provided:
double mtrs_per_unit = 1.0;
if (record[A_UNITS] == "US survey foot")
mtrs_per_unit = US_METERS_PER_FT;
else if (record[A_UNITS].contains("foot")) // THIS IS INTERNATIONAL FOOT, NOT EXACT FOR MANY INTERNATIONAL VARIETIES
mtrs_per_unit = MTRS_PER_FT;
else if (!record[A_UNITS].contains("metre") || (record[A_UNITS] == "kilometre"))
{
// ### SKIP THIS MESSAGE BUT BE AWARE THAT THIS PROJECTION WON'T BE REPRESENTED IN DB ###
//ossimNotify(ossimNotifyLevel_WARN)<<MODULE<<"EPSG:"<<pcs_code<<" units of <"
// <<record[A_UNITS]<<"> not presently supported."<<endl;
return 0;
}
// First create a datum given the datum code in the record:
ossim_uint32 gcs_code = record[A_DATUM_CODE].toUInt32();
const ossimDatum* datum = ossimEpsgDatumFactory::instance()->create(gcs_code);
if (!datum)
{
// Default to WGS 84 -- this may throw an exception:
datum = ossimEpsgDatumFactory::instance()->create(ossimString("EPSG:4326"));
datum_valid = false;
}
const ossimEllipsoid* ellipsoid = datum->ellipsoid();
ossimGpt origin(0,0,0);
ossimString proj_type = record[A_PROJ_TYPE];
if (proj_type.contains("Transverse Mercator"))
{
origin.lat = decodeSexagesimalDms(record[A_NAT_ORG_LAT]);
origin.lon = decodeSexagesimalDms(record[A_NAT_ORG_LON]);
double fe = mtrs_per_unit*record[A_FALSE_EASTING].toDouble();
double fn = mtrs_per_unit*record[A_FALSE_NORTHING].toDouble();
double sf = record[A_NAT_ORG_SCALE].toDouble();
proj = new ossimTransMercatorProjection(*ellipsoid, origin, fe, fn, sf);
}
else if (proj_type.contains("Lambert Conic Conformal (1SP)"))
{
origin.lat = decodeSexagesimalDms(record[A_NAT_ORG_LAT]);
origin.lon = decodeSexagesimalDms(record[A_NAT_ORG_LON]);
double fe = mtrs_per_unit*record[A_FALSE_EASTING].toDouble();
double fn = mtrs_per_unit*record[A_FALSE_NORTHING].toDouble();
proj = new ossimLambertConformalConicProjection(*ellipsoid, origin, origin.lat,
origin.lat, fe, fn);
}
else if (proj_type.contains("Lambert Conic Conformal (2SP)"))
{
origin.lat = decodeSexagesimalDms(record[A_FALSE_ORG_LAT]);
origin.lon = decodeSexagesimalDms(record[A_FALSE_ORG_LON]);
double p1 = decodeSexagesimalDms(record[A_STD_PARL_1_LAT]);
double p2 = decodeSexagesimalDms(record[A_STD_PARL_2_LAT]);
double fe = mtrs_per_unit*record[A_FALSE_ORG_EASTING].toDouble();
double fn = mtrs_per_unit*record[A_FALSE_ORG_NORTHING].toDouble();
proj = new ossimLambertConformalConicProjection(*ellipsoid, origin, p1, p2, fe, fn);
}
else if (proj_type.contains("Cassini"))
{
origin.lat = decodeSexagesimalDms(record[A_NAT_ORG_LAT]);
origin.lon = decodeSexagesimalDms(record[A_NAT_ORG_LON]);
double fe = mtrs_per_unit*record[A_FALSE_EASTING].toDouble();
double fn = mtrs_per_unit*record[A_FALSE_NORTHING].toDouble();
proj = new ossimCassiniProjection(*ellipsoid, origin, fe, fn);
}
else if (proj_type.contains("Mercator (1SP)"))
{
origin.lat = decodeSexagesimalDms(record[A_NAT_ORG_LAT]);
origin.lon = decodeSexagesimalDms(record[A_NAT_ORG_LON]);
double fe = mtrs_per_unit*record[A_FALSE_EASTING].toDouble();
double fn = mtrs_per_unit*record[A_FALSE_NORTHING].toDouble();
double sf = record[A_NAT_ORG_SCALE].toDouble();
proj = new ossimMercatorProjection(*ellipsoid, origin, fe, fn, sf);
}
else if (proj_type.contains("Albers"))
{
origin.lat = decodeSexagesimalDms(record[A_FALSE_ORG_LAT]);
origin.lon = decodeSexagesimalDms(record[A_FALSE_ORG_LON]);
double p1 = decodeSexagesimalDms(record[A_STD_PARL_1_LAT]);
double p2 = decodeSexagesimalDms(record[A_STD_PARL_2_LAT]);
double fe = mtrs_per_unit*record[A_FALSE_ORG_EASTING].toDouble();
double fn = mtrs_per_unit*record[A_FALSE_ORG_NORTHING].toDouble();
proj = new ossimAlbersProjection(*ellipsoid, origin, p1, p2, fe, fn);
}
else if (proj_type.contains("Equidistant Cylindrical"))
{
origin.lat = decodeSexagesimalDms(record[A_STD_PARL_1_LAT]);
origin.lon = decodeSexagesimalDms(record[A_NAT_ORG_LON]);
double fe = mtrs_per_unit*record[A_FALSE_EASTING].toDouble();
double fn = mtrs_per_unit*record[A_FALSE_NORTHING].toDouble();
proj = new ossimEquDistCylProjection(*ellipsoid, origin, fe, fn);
}
else if (proj_type.contains("New Zealand Map Grid"))
{
origin.lat = decodeSexagesimalDms(record[A_NAT_ORG_LAT]);
origin.lon = decodeSexagesimalDms(record[A_NAT_ORG_LON]);
double fe = mtrs_per_unit*record[A_FALSE_EASTING].toDouble();
double fn = mtrs_per_unit*record[A_FALSE_NORTHING].toDouble();
ossimNewZealandMapGridProjection* nz_proj = new ossimNewZealandMapGridProjection;
nz_proj->setOrigin(origin);
nz_proj->setFalseEastingNorthing(fe, fn);
proj = nz_proj;
}
else
{
// Can't handle it now.
//ossimNotify(ossimNotifyLevel_FATAL)<<MODULE<<"EPSG:"<<record[A_CODE]<<" \""<<proj_type<<"\" "
// "not presently supported. Returning NULL projection..."<<endl;
return 0;
}
proj->setDatum(datum);
proj->setPcsCode(pcs_code);
return proj;
}