3

I am trying to create a Custom Affine Projection in QGIS, but when I Validate I get an error:

This WKT projection definition is not valid: Missing METHOD node

Here's my WKT:

DERIVEDPROJCRS["WA83-SF_WSDOT",
    BASEPROJCRS["NAD83(2011) / Washington South (ftUS)",
    GEOGCS["NAD83(2011)",
        DATUM["NAD83_National_Spatial_Reference_System_2011",
            SPHEROID["GRS 1980",6378137,298.257222101],
            TOWGS84[0,0,0,0,0,0,0]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.0174532925199433,
            AUTHORITY["EPSG","9122"]],
        AUTHORITY["EPSG","6318"]],
        CONVERSION["Washington South (ftUS)"],
            METHOD["Lambert_Conformal_Conic_2SP",
                ID["EPSG",9802
                ]
            ],
    PARAMETER["latitude_of_origin",45.3333333333333],
    PARAMETER["central_meridian",-120.5],
    PARAMETER["standard_parallel_1",47.3333333333333],
    PARAMETER["standard_parallel_2",45.8333333333333],
    PARAMETER["false_easting",1640416.667],
    PARAMETER["false_northing",0],
    UNIT["US survey foot",0.304800609601219],
    AXIS["Easting",EAST],
    AXIS["Northing",NORTH],
    AUTHORITY["EPSG","6599"]]
    DERIVINGCONVERSION["Affine",
        METHOD["Affine parametric transformation",
            ID["EPSG",9624
            ]
        ],
        PARAMETER["A0",328083.3333,
            LENGTHUNIT["US survey foot",0.304800609601219],
            ID["EPSG",8623
            ]
        ],
        PARAMETER["A1",1.00004966246624,
            SCALEUNIT["coefficient",1
            ],
            ID["EPSG",8624
            ]
        ],
        PARAMETER["A2",0,
            SCALEUNIT["coefficient",1
            ],
            ID["EPSG",8625
            ]
        ],
        PARAMETER["B0",328083.3333,
            LENGTHUNIT["US survey foot",0.304800609601219],
            ID["EPSG",8639
            ]
        ],
        PARAMETER["B1",0,
            SCALEUNIT["coefficient",1
            ],
            ID["EPSG",8640
            ]
        ],
        PARAMETER["B2",1.00004966246624,
            SCALEUNIT["coefficient",1
            ],
            ID["EPSG",8641
            ]
        ]
    ],
    CS[Cartesian,2
    ],
    AXIS["(E)",east,
        ORDER[1
        ],
        LENGTHUNIT["US survey foot",0.304800609601219]
    ],
    AXIS["(N)",north,
        ORDER[2
        ],
        LENGTHUNIT["US survey foot",0.304800609601219]
    ]
]

1 Answer 1

2

The error shows that the CONVERSION node is being closed before the METHOD has been defined, here:

        CONVERSION["Washington South (ftUS)"],
            METHOD["Lambert_Conformal_Conic_2SP",

It should look like this:

        CONVERSION["Washington South (ftUS)",
            METHOD["Lambert_Conformal_Conic_2SP",

Also, there is a comma missing before defining the DERIVINGCONVERSION, here:

    AUTHORITY["EPSG","6599"]]
    DERIVINGCONVERSION["Affine",

It should look like this:

    AUTHORITY["EPSG","6599"]],
    DERIVINGCONVERSION["Affine",

Likewise, I'm not sure if the units of measurement and the order of the axes should go in the BASEPROJCRS node, I usually put them only in the DERIVEDPROJCRS node, that is, at the end. Regarding the BASEPROJCRS identifier, I generally remove it. I am not sure these last considerations are necessary.
At least the string works, if you want to test against it:

DERIVEDPROJCRS["WA83-SF_WSDOT",
    BASEPROJCRS["NAD83(2011) / Washington South (ftUS)",
        BASEGEOGCRS["NAD83(2011)",
            DATUM["NAD83 (National Spatial Reference System 2011)",
                ELLIPSOID["GRS 1980",6378137,298.257222101,
                    LENGTHUNIT["metre",1]]],
            PRIMEM["Greenwich",0,
                ANGLEUNIT["degree",0.0174532925199433]],
            ID["EPSG",6318]],
        CONVERSION["SPCS83 Washington South zone (US Survey feet)",
            METHOD["Lambert Conic Conformal (2SP)",
                ID["EPSG",9802]],
            PARAMETER["Latitude of false origin",45.3333333333333,
                ANGLEUNIT["degree",0.0174532925199433],
                ID["EPSG",8821]],
            PARAMETER["Longitude of false origin",-120.5,
                ANGLEUNIT["degree",0.0174532925199433],
                ID["EPSG",8822]],
            PARAMETER["Latitude of 1st standard parallel",47.3333333333333,
                ANGLEUNIT["degree",0.0174532925199433],
                ID["EPSG",8823]],
            PARAMETER["Latitude of 2nd standard parallel",45.8333333333333,
                ANGLEUNIT["degree",0.0174532925199433],
                ID["EPSG",8824]],
            PARAMETER["Easting at false origin",1640416.667,
                LENGTHUNIT["US survey foot",0.304800609601219],
                ID["EPSG",8826]],
            PARAMETER["Northing at false origin",0,
                LENGTHUNIT["US survey foot",0.304800609601219],
                ID["EPSG",8827]]]],
    DERIVINGCONVERSION["Affine",
        METHOD["Affine parametric transformation",
            ID["EPSG",9624]],
        PARAMETER["A0",328083.3333,
            LENGTHUNIT["US survey foot",0.304800609601219],
            ID["EPSG",8623]],
        PARAMETER["A1",1.00004966246624,
            SCALEUNIT["coefficient",1],
            ID["EPSG",8624]],
        PARAMETER["A2",0,
            SCALEUNIT["coefficient",1],
            ID["EPSG",8625]],
        PARAMETER["B0",328083.3333,
            LENGTHUNIT["US survey foot",0.304800609601219],
            ID["EPSG",8639]],
        PARAMETER["B1",0,
            SCALEUNIT["coefficient",1],
            ID["EPSG",8640]],
        PARAMETER["B2",1.00004966246624,
            SCALEUNIT["coefficient",1],
            ID["EPSG",8641]]],
    CS[Cartesian,2],
    AXIS["(E)",east,
        ORDER[1],
        LENGTHUNIT["US survey foot",0.304800609601219]],
    AXIS["(N)",north,
        ORDER[2],
        LENGTHUNIT["US survey foot",0.304800609601219]]]

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