Google maps spatial reference system
What is Google map's spatial reference system using when you enter a lat, long into the maps search bar?
I've found hints that it might be WGS84 but after converting to that coordinate system, nothing shows up when i paste the coordinates into the google maps search box.
I am converting from GDA MGA 56.
Sample:
- Input MGA56 coords: 336301, 6253363
- Expected WGS86 coords: -33.847334079开发者_StackOverflow中文版3201, 151.230631835944
- I get: 16834916.928327594 -4008321.1020318186
Spatial coord systems:
- EPSG:28356 for MGA56
- EPSG:900913 for WGS86 (google maps)
I am using geotools to do the transform:
CoordinateReferenceSystem crsMga56 = CRS.parseWKT(mga56);
CoordinateReferenceSystem crsGmaps = CRS.parseWKT(gmaps);
Coordinate coordinate = new Coordinate(336301, 6253363);
Point point = new GeometryFactory().createPoint(coordinate);
MathTransform transform = CRS.findMathTransform(crsMga56, crsGmaps);
Geometry geometry = JTS.transform(point, transform);
I know the transform is not correct, as when i use an online tool it gives me the correct coords. http://www.environment.gov.au/cgi-bin/transform/mga2geo_gda.pl?east=336301&north=6253363&zone=56
Google uses a spherical mercator projection based on WGS84. There's a writeup on the OpenLayers website.
If it is any use, we found GeoTools were changing the JVM so that lat & long were the opposite way around (i.e. 151,-33), which might explain why you are getting out of bounds {151 > 90}) it was a nightmare to find
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