Opened 8 years ago

Closed 8 years ago

#3136 closed defect (fixed)

EPSG:3785 does not support spherical mercator hack

Reported by: topher Owned by: warmerdam
Priority: normal Milestone: 1.6.3
Component: OGR_SRS Version: unspecified
Severity: normal Keywords: google mercator
Cc:

Description

testepg EPSG:3785 does not include Google mercator extension node.

Change History (3)

comment:1 Changed 8 years ago by warmerdam

Keywords: google mercator added
Milestone: 1.7.0
Status: newassigned

testepsg reports this:

{{[ WKT[EPSG:3785] = PROJCS["Popular Visualisation CRS / Mercator (deprecated)",

GEOGCS["Popular Visualisation CRS",

DATUM["Popular_Visualisation_Datum",

SPHEROID["Popular Visualisation Sphere",6378137,0,

AUTHORITY["EPSG","7059"]],

TOWGS84[0,0,0,0,0,0,0], AUTHORITY["EPSG","6055"]],

PRIMEM["Greenwich",0,

AUTHORITY["EPSG","8901"]],

UNIT["degree",0.01745329251994328,

AUTHORITY["EPSG","9122"]],

AUTHORITY["EPSG","4055"]],

UNIT["metre",1,

AUTHORITY["EPSG","9001"]],

PROJECTIONMercator_1SP?, PARAMETER["central_meridian",0], PARAMETER["scale_factor",1], PARAMETER["false_easting",0], PARAMETER["false_northing",0], AUTHORITY["EPSG","3785"], AXIS["X",EAST], AXIS["Y",NORTH]]

}}}

while testepsg EPSG:9009l3 reports:

WKT[EPSG:900913] =
PROJCS["Google Maps Global Mercator",
    GEOGCS["WGS 84",
        DATUM["WGS_1984",
            SPHEROID["WGS 84",6378137,298.257223563,
                AUTHORITY["EPSG","7030"]],
            AUTHORITY["EPSG","6326"]],
        PRIMEM["Greenwich",0,
            AUTHORITY["EPSG","8901"]],
        UNIT["degree",0.01745329251994328,
            AUTHORITY["EPSG","9122"]],
        AUTHORITY["EPSG","4326"]],
    PROJECTION["Mercator_2SP"],
    PARAMETER["standard_parallel_1",0],
    PARAMETER["latitude_of_origin",0],
    PARAMETER["central_meridian",0],
    PARAMETER["false_easting",0],
    PARAMETER["false_northing",0],
    UNIT["Meter",1],
    EXTENSION["PROJ4","+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +
x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext  +no_defs"],
    AUTHORITY["EPSG","900913"]]

The 900913 extension node is important to get the coordinate system to evaluate properly. It is driven by an entry in cubewerx_extra.wkt. The 3785 entry is driven by an epsg pcs.csv entry which does not provide for the override. We need a way of representing this properly from the epsg database or perhaps of at least overriding it somehow.

comment:2 Changed 8 years ago by warmerdam

Milestone: 1.7.01.6.3

I have modified the epsg->wkt translation process to insert the extension node in trunk (r17670), and 1.6 branch (r17671).

comment:3 Changed 8 years ago by warmerdam

Resolution: fixed
Status: assignedclosed

added testing in trunk (r17672).

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