예제 #1
0
bool QgsCustomProjectionDialog::saveCRS( QgsCoordinateReferenceSystem myCRS, QString myName, QString myId, bool newEntry )
{
  QString mySql;
  int return_id;
  QString myProjectionAcronym  = myCRS.projectionAcronym();
  QString myEllipsoidAcronym   =  myCRS.ellipsoidAcronym();
  QgsDebugMsg( QString( "Saving a CRS:%1, %2, %3" ).arg( myName ).arg( myCRS.toProj4() ).arg( newEntry ) );
  if ( newEntry )
  {
    return_id = myCRS.saveAsUserCRS( myName );
    if ( return_id == -1 )
      return false;
    else
      myId = QString::number( return_id );
  }
  else
  {
    mySql = "update tbl_srs set description="
            + quotedValue( myName )
            + ",projection_acronym=" + quotedValue( myProjectionAcronym )
            + ",ellipsoid_acronym=" + quotedValue( myEllipsoidAcronym )
            + ",parameters=" + quotedValue( myCRS.toProj4() )
            + ",is_geo=0" // <--shamelessly hard coded for now
            + " where srs_id=" + quotedValue( myId )
            ;
    QgsDebugMsg( mySql );
    sqlite3      *myDatabase;
    const char   *myTail;
    sqlite3_stmt *myPreparedStatement;
    int           myResult;
    //check if the db is available
    myResult = sqlite3_open( QgsApplication::qgisUserDbFilePath().toUtf8(), &myDatabase );
    if ( myResult != SQLITE_OK )
    {
      QgsDebugMsg( QString( "Can't open database: %1 \n please notify  QGIS developers of this error \n %2 (file name) " ).arg( sqlite3_errmsg( myDatabase ) ).arg( QgsApplication::qgisUserDbFilePath() ) );
      // XXX This will likely never happen since on open, sqlite creates the
      //     database if it does not exist.
      Q_ASSERT( myResult == SQLITE_OK );
    }
    myResult = sqlite3_prepare( myDatabase, mySql.toUtf8(), mySql.toUtf8().length(), &myPreparedStatement, &myTail );
    sqlite3_step( myPreparedStatement );
    // XXX Need to free memory from the error msg if one is set
    if ( myResult != SQLITE_OK )
    {
      QgsDebugMsg( QString( "failed to write to database in custom projection dialog: %1 [%2]" ).arg( mySql ).arg( sqlite3_errmsg( myDatabase ) ) );
    }

    sqlite3_finalize( myPreparedStatement );
    // close sqlite3 db
    sqlite3_close( myDatabase );
    if ( myResult != SQLITE_OK )
      return false;
  }
  existingCRSparameters[myId] = myCRS.toProj4();
  existingCRSnames[myId] = myName;

  QgsCRSCache::instance()->updateCRSCache( QString( "USER:%1" ).arg( myId ) );

  // If we have a projection acronym not in the user db previously, add it.
  // This is a must, or else we can't select it from the vw_srs table.
  // Actually, add it always and let the SQL PRIMARY KEY remove duplicates.
  insertProjection( myProjectionAcronym );

  return true;
}
예제 #2
0
bool QgsDistanceArea::setEllipsoid( const QString& ellipsoid )
{
  QString radius, parameter2;
  //
  // SQLITE3 stuff - get parameters for selected ellipsoid
  //
  sqlite3      *myDatabase;
  const char   *myTail;
  sqlite3_stmt *myPreparedStatement;
  int           myResult;

  // Shortcut if ellipsoid is none.
  if ( ellipsoid == GEO_NONE )
  {
    mEllipsoid = GEO_NONE;
    return true;
  }

  // Check if we have a custom projection, and set from text string.
  // Format is "PARAMETER:<semi-major axis>:<semi minor axis>
  // Numbers must be with (optional) decimal point and no other separators (C locale)
  // Distances in meters.  Flattening is calculated.
  if ( ellipsoid.startsWith( "PARAMETER" ) )
  {
    QStringList paramList = ellipsoid.split( ':' );
    bool semiMajorOk, semiMinorOk;
    double semiMajor = paramList[1].toDouble( & semiMajorOk );
    double semiMinor = paramList[2].toDouble( & semiMinorOk );
    if ( semiMajorOk && semiMinorOk )
    {
      return setEllipsoid( semiMajor, semiMinor );
    }
    else
    {
      return false;
    }
  }

  // Continue with PROJ.4 list of ellipsoids.

  //check the db is available
  myResult = sqlite3_open_v2( QgsApplication::srsDbFilePath().toUtf8().data(), &myDatabase, SQLITE_OPEN_READONLY, nullptr );
  if ( myResult )
  {
    QgsMessageLog::logMessage( QObject::tr( "Can't open database: %1" ).arg( sqlite3_errmsg( myDatabase ) ) );
    // XXX This will likely never happen since on open, sqlite creates the
    //     database if it does not exist.
    return false;
  }
  // Set up the query to retrieve the projection information needed to populate the ELLIPSOID list
  QString mySql = "select radius, parameter2 from tbl_ellipsoid where acronym='" + ellipsoid + '\'';
  myResult = sqlite3_prepare( myDatabase, mySql.toUtf8(), mySql.toUtf8().length(), &myPreparedStatement, &myTail );
  // XXX Need to free memory from the error msg if one is set
  if ( myResult == SQLITE_OK )
  {
    if ( sqlite3_step( myPreparedStatement ) == SQLITE_ROW )
    {
      radius = QString( reinterpret_cast< const char * >( sqlite3_column_text( myPreparedStatement, 0 ) ) );
      parameter2 = QString( reinterpret_cast< const char * >( sqlite3_column_text( myPreparedStatement, 1 ) ) );
    }
  }
  // close the sqlite3 statement
  sqlite3_finalize( myPreparedStatement );
  sqlite3_close( myDatabase );

  // row for this ellipsoid wasn't found?
  if ( radius.isEmpty() || parameter2.isEmpty() )
  {
    QgsDebugMsg( QString( "setEllipsoid: no row in tbl_ellipsoid for acronym '%1'" ).arg( ellipsoid ) );
    return false;
  }

  // get major semiaxis
  if ( radius.left( 2 ) == "a=" )
    mSemiMajor = radius.mid( 2 ).toDouble();
  else
  {
    QgsDebugMsg( QString( "setEllipsoid: wrong format of radius field: '%1'" ).arg( radius ) );
    return false;
  }

  // get second parameter
  // one of values 'b' or 'f' is in field parameter2
  // second one must be computed using formula: invf = a/(a-b)
  if ( parameter2.left( 2 ) == "b=" )
  {
    mSemiMinor = parameter2.mid( 2 ).toDouble();
    mInvFlattening = mSemiMajor / ( mSemiMajor - mSemiMinor );
  }
  else if ( parameter2.left( 3 ) == "rf=" )
  {
    mInvFlattening = parameter2.mid( 3 ).toDouble();
    mSemiMinor = mSemiMajor - ( mSemiMajor / mInvFlattening );
  }
  else
  {
    QgsDebugMsg( QString( "setEllipsoid: wrong format of parameter2 field: '%1'" ).arg( parameter2 ) );
    return false;
  }

  QgsDebugMsg( QString( "setEllipsoid: a=%1, b=%2, 1/f=%3" ).arg( mSemiMajor ).arg( mSemiMinor ).arg( mInvFlattening ) );


  // get spatial ref system for ellipsoid
  QString proj4 = "+proj=longlat +ellps=" + ellipsoid + " +no_defs";
  QgsCoordinateReferenceSystem destCRS;
  destCRS.createFromProj4( proj4 );
  //TODO: createFromProj4 used to save to the user database any new CRS
  // this behavior was changed in order to separate creation and saving.
  // Not sure if it necessary to save it here, should be checked by someone
  // familiar with the code (should also give a more descriptive name to the generated CRS)
  if ( destCRS.srsid() == 0 )
  {
    QString myName = QString( " * %1 (%2)" )
                     .arg( QObject::tr( "Generated CRS", "A CRS automatically generated from layer info get this prefix for description" ),
                           destCRS.toProj4() );
    destCRS.saveAsUserCRS( myName );
  }
  //

  // set transformation from project CRS to ellipsoid coordinates
  mCoordTransform->setDestCRS( destCRS );

  mEllipsoid = ellipsoid;

  // precalculate some values for area calculations
  computeAreaInit();

  return true;
}
예제 #3
0
bool QgsDistanceArea::setEllipsoid( const QString& ellipsoid )
{
  // Shortcut if ellipsoid is none.
  if ( ellipsoid == GEO_NONE )
  {
    mEllipsoid = GEO_NONE;
    return true;
  }

  // Check if we have a custom projection, and set from text string.
  // Format is "PARAMETER:<semi-major axis>:<semi minor axis>
  // Numbers must be with (optional) decimal point and no other separators (C locale)
  // Distances in meters.  Flattening is calculated.
  if ( ellipsoid.startsWith( "PARAMETER" ) )
  {
    QStringList paramList = ellipsoid.split( ":" );
    bool semiMajorOk, semiMinorOk;
    double semiMajor = paramList[1].toDouble( & semiMajorOk );
    double semiMinor = paramList[2].toDouble( & semiMinorOk );
    if ( semiMajorOk && semiMinorOk )
    {
      return setEllipsoid( semiMajor, semiMinor );
    }
    else
    {
      return false;
    }
  }

  // Continue with PROJ.4 list of ellipsoids.
  QgsEllipsoidCache::Params params = QgsEllipsoidCache::instance()->getParams( ellipsoid );

  // row for this ellipsoid wasn't found?
  if ( params.radius.isEmpty() || params.parameter2.isEmpty() )
  {
    QgsDebugMsg( QString( "setEllipsoid: no row in tbl_ellipsoid for acronym '%1'" ).arg( ellipsoid ) );
    return false;
  }

  // get major semiaxis
  if ( params.radius.left( 2 ) == "a=" )
    mSemiMajor = params.radius.mid( 2 ).toDouble();
  else
  {
    QgsDebugMsg( QString( "setEllipsoid: wrong format of radius field: '%1'" ).arg( params.radius ) );
    return false;
  }

  // get second parameter
  // one of values 'b' or 'f' is in field parameter2
  // second one must be computed using formula: invf = a/(a-b)
  if ( params.parameter2.left( 2 ) == "b=" )
  {
    mSemiMinor = params.parameter2.mid( 2 ).toDouble();
    mInvFlattening = mSemiMajor / ( mSemiMajor - mSemiMinor );
  }
  else if ( params.parameter2.left( 3 ) == "rf=" )
  {
    mInvFlattening = params.parameter2.mid( 3 ).toDouble();
    mSemiMinor = mSemiMajor - ( mSemiMajor / mInvFlattening );
  }
  else
  {
    QgsDebugMsg( QString( "setEllipsoid: wrong format of parameter2 field: '%1'" ).arg( params.parameter2 ) );
    return false;
  }

  QgsDebugMsg( QString( "setEllipsoid: a=%1, b=%2, 1/f=%3" ).arg( mSemiMajor ).arg( mSemiMinor ).arg( mInvFlattening ) );


  // get spatial ref system for ellipsoid
  QString proj4 = "+proj=longlat +ellps=" + ellipsoid + " +no_defs";
  QgsCoordinateReferenceSystem destCRS = QgsCRSCache::instance()->crsByProj4( proj4 );
  //TODO: createFromProj4 used to save to the user database any new CRS
  // this behavior was changed in order to separate creation and saving.
  // Not sure if it necessary to save it here, should be checked by someone
  // familiar with the code (should also give a more descriptive name to the generated CRS)
  if ( destCRS.srsid() == 0 )
  {
    QString myName = QString( " * %1 (%2)" )
                     .arg( QObject::tr( "Generated CRS", "A CRS automatically generated from layer info get this prefix for description" ) )
                     .arg( destCRS.toProj4() );
    destCRS.saveAsUserCRS( myName );
  }
  //

  // set transformation from project CRS to ellipsoid coordinates
  mCoordTransform->setDestCRS( destCRS );

  mEllipsoid = ellipsoid;

  // precalculate some values for area calculations
  computeAreaInit();

  return true;
}