# Copyright 2005-2018 ECMWF.
#
# This software is licensed under the terms of the Apache Licence Version 2.0
# which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
# 
# In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
# virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
#

unsigned[2] Nx  : dump;
alias Ni =  Nx;
alias numberOfPointsAlongXAxis =  Nx;
alias geography.Nx=Nx;

unsigned[2] Ny  : dump;
alias Nj =  Ny;
alias numberOfPointsAlongYAxis =  Ny;
alias geography.Ny=Ny;

#  La1 - latitude of first grid point
signed[3] latitudeOfFirstGridPoint :  edition_specific;
meta geography.latitudeOfFirstGridPointInDegrees
      scale(latitudeOfFirstGridPoint,oneConstant,grib1divider,truncateDegrees) : dump;
alias La1 = latitudeOfFirstGridPoint;
alias La1InDegrees=latitudeOfFirstGridPointInDegrees;
#meta latitudeOfFirstGridPointInMicrodegrees times(latitudeOfFirstGridPoint,thousand);


#  Lo1 - longitude of first grid point
signed[3] longitudeOfFirstGridPoint  : edition_specific;
meta geography.longitudeOfFirstGridPointInDegrees
      scale(longitudeOfFirstGridPoint,oneConstant,grib1divider,truncateDegrees) : dump;
alias Lo1 = longitudeOfFirstGridPoint;
alias Lo1InDegrees = longitudeOfFirstGridPointInDegrees;
#meta longitudeOfFirstGridPointInMicrodegrees times(longitudeOfFirstGridPoint,thousand);

#  Resolution and component flags
include "grib1/resolution_flags.def";

#  LoV - orientation of the grid; i.e.  the east longitude value of the meridian which is parallel to the Y-axis
signed[3] LoV : edition_specific  ;
meta geography.LoVInDegrees
    scale(LoV,oneConstant,grib1divider,truncateDegrees) : dump;
alias orientationOfTheGrid = LoV;
alias orientationOfTheGridInDegrees = LoVInDegrees;

#  Dx - X-direction grid length
unsigned[3] DxInMetres  : dump;
alias xDirectionGridLength=DxInMetres;
alias geography.DxInMetres=DxInMetres ;
alias Dx = DxInMetres;
alias Di = DxInMetres;


#  Dy - Y-direction grid length
unsigned[3] DyInMetres  : dump;
alias yDirectionGridLength=DyInMetres;
alias geography.DyInMetres=DyInMetres;
alias Dy= DyInMetres;
alias Dj = DyInMetres;


unsigned[1] projectionCentreFlag  : dump;
# Also add the old spelling  of "centre" for backward compatibility
alias projectionCenterFlag=projectionCentreFlag;

# for change_scanning_direction
alias yFirst=latitudeOfFirstGridPointInDegrees;
alias xFirst=longitudeOfFirstGridPointInDegrees;

include "grib1/scanning_mode.def";

#  Latin 1 - first latitude from the pole at which the secant cone cuts the sphere
signed[3] Latin1 : edition_specific;
meta geography.Latin1InDegrees scale(Latin1,oneConstant,grib1divider,truncateDegrees) : dump;
alias firstLatitude=Latin1;
alias firstLatitudeInDegrees=Latin1InDegrees;

# GRIB Edition 1 does not have the LaD parameter so we use Latin1 instead
constant LaDInDegrees = Latin1InDegrees : dump;
alias geography.LaDInDegrees=LaDInDegrees;

#  Latin 2 - second latitude from the pole at which the secant cone cuts the sphere
signed[3] Latin2 :edition_specific;
alias secondLatitude=Latin2;
meta geography.Latin2InDegrees scale(Latin2,oneConstant,grib1divider,truncateDegrees) : dump;
alias secondLatitudeInDegrees=Latin2InDegrees;

signed[3] latitudeOfSouthernPole : no_copy;
meta  geography.latitudeOfSouthernPoleInDegrees
        scale(latitudeOfSouthernPole,oneConstant,grib1divider,truncateDegrees) : dump;

signed[3] longitudeOfSouthernPole : no_copy;
meta  geography.longitudeOfSouthernPoleInDegrees
        scale(longitudeOfSouthernPole,oneConstant,grib1divider,truncateDegrees) : dump;

meta numberOfDataPoints number_of_points(Nx,Ny,PLPresent,pl) : dump;
alias numberOfPoints=numberOfDataPoints;
meta numberOfValues number_of_values(values,bitsPerValue,numberOfDataPoints,
                                    bitmapPresent,bitmap,numberOfCodedValues) : dump;
#alias ls.valuesCount=numberOfValues;

iterator lambert_conformal(numberOfPoints,missingValue,values,
          radius,Nx,Ny,
          LoVInDegrees,LaDInDegrees,
          Latin1InDegrees,Latin2InDegrees,
          latitudeOfFirstGridPointInDegrees,longitudeOfFirstGridPointInDegrees,
          Dx,Dy,
          iScansNegatively,
          jScansPositively,
          jPointsAreConsecutive,
          alternativeRowScanning);


meta latLonValues latlonvalues(values);
alias latitudeLongitudeValues=latLonValues;
meta latitudes latitudes(values,0);
meta longitudes longitudes(values,0);
meta distinctLatitudes latitudes(values,1);
meta distinctLongitudes longitudes(values,1);

nearest lambert_conformal(values,radius,Nx,Ny);

pad padding_grid3_1(2);

# END   1/grid_definition.lambert_conformal ----------------------------------------------------------------------

