check Smith Sandwell projection

[mdsumner]

Follow up on this https://lists.osgeo.org/pipermail/proj/2019-May/008539.html

Currently we use

raadtools/R/topo.R

Lines 2 to 25 in e63b5cf

	'<VRTDataset rasterXSize="21600" rasterYSize="17280">
	<GeoTransform>0.0, 1855.325, 0.0000000000000000e+000, 15987768, 0.0000000000000000e+000,-1850.436</GeoTransform>
	<SRS>PROJCS["unnamed",
	GEOGCS["Normal Sphere (r=6370997)",
	DATUM["unknown",
	SPHEROID["sphere",6370997,0]],
	PRIMEM["Greenwich",0],
	UNIT["degree",0.0174532925199433]],
	PROJECTION["Mercator_1SP"],
	PARAMETER["central_meridian",0],
	PARAMETER["scale_factor",1],
	PARAMETER["false_easting",0],
	PARAMETER["false_northing",0]]</SRS>
	<Metadata />
	<VRTRasterBand dataType="Int16" band="1" subClass="VRTRawRasterBand">
	<Metadata />
	<SourceFilename relativeToVRT="1">ssbinfile</SourceFilename>
	<SourceBand>1</SourceBand>
	<ImageOffset>0</ImageOffset>
	<PixelOffset>2</PixelOffset>
	<LineOffset>43200</LineOffset>
	<ByteOrder>MSB</ByteOrder>
	</VRTRasterBand>
	</VRTDataset>'

for version 18.1

(There's no .ers for 19.1 AustralianAntarcticDivision/blueant#20)

[mdsumner]

.vrt/topo_18.1_atlantic.vrt
Driver: VRT/Virtual Raster
Files: /rdsi/PUBLIC/raad/data/topex.ucsd.edu/pub/global_topo_1min/.vrt/topo_18.1_atlantic.vrt
       /rdsi/PUBLIC/raad/data/topex.ucsd.edu/pub/global_topo_1min/.vrt/topo_18.1.vrt
Size is 21600, 17280
Coordinate System is:
PROJCS["unnamed",
    GEOGCS["Normal Sphere (r=6370997)",
        DATUM["unknown",
            SPHEROID["sphere",6370997,0]],
        PRIMEM["Greenwich",0],
        UNIT["degree",0.0174532925199433]],
    PROJECTION["Mercator_1SP"],
    PARAMETER["central_meridian",0],
    PARAMETER["scale_factor",1],
    PARAMETER["false_easting",0],
    PARAMETER["false_northing",0]]
Origin = (-20037510.000000000000000,15987768.000000000000000)
Pixel Size = (1855.325000000000045,-1850.435999999999922)
Corner Coordinates:
Upper Left  (-20037510.000,15987768.000) (179d47'53.73"E, 80d42'10.00"N)
Lower Left  (-20037510.000,-15987766.080) (179d47'53.73"E, 80d42' 9.99"S)
Upper Right (20037510.000,15987768.000) (179d47'53.73"W, 80d42'10.00"N)
Lower Right (20037510.000,-15987766.080) (179d47'53.73"W, 80d42' 9.99"S)
Center      (   0.0000000,   0.9600000) (  0d 0' 0.01"E,  0d 0' 0.03"N)
Band 1 Block=128x128 Type=Int16, ColorInterp=Undefined

We already close, wait for any updates and then conform:

Origin = (-20037148.342789199000000,15540200.914741000000000)

Pixel Size = (1855.324846554555500,-1855.324846554560700)

Metadata:


Upper Left  (-20037148.343,15540200.915) (179d59'48.36"W, 80d 0' 8.37"N)

Lower Left  (-20037148.343,-15540200.915) (179d59'48.36"W, 80d 0' 8.37"S)

Upper Right (20037868.343,15540200.915) (179d59'48.36"W, 80d 0' 8.37"N)

Lower Right (20037868.343,-15540200.915) (179d59'48.36"W, 80d 0' 8.37"S)

Center      (     360.000,       0.000) (  0d 0'11.64"E,  0d 0' 0.01"N)