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@onderaltintas
Forked from springmeyer/degress2meters.js
Last active April 12, 2022 01:38
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javascript coordinate conversions between 900913(3857) - 4326(lat lon)
var degrees2meters = function(lon,lat) {
var x = lon * 20037508.34 / 180;
var y = Math.log(Math.tan((90 + lat) * Math.PI / 360)) / (Math.PI / 180);
y = y * 20037508.34 / 180;
return [x, y]
}
//test
lon= -77.035974
lat = 38.898717
console.log(degrees2meters(lon,lat))
// should result in: -8575605.398444, 4707174.018280
var meters2degress = function(x,y) {
var lon = x * 180 / 20037508.34 ;
//thanks magichim @ github for the correction
var lat = Math.atan(Math.exp(y * Math.PI / 20037508.34)) * 360 / Math.PI - 90;
return [lon, lat]
}
//test
x= -8575605.398444
y = 4707174.018280
console.log(meters2degress(x,y))
//should result in: -77.035974, 38.898717
@vuhung3990
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you saved my life, thank you

@onderaltintas
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you saved my life, thank you

I'm glad that I could help. But don't forget that it is just to translate 4326 to 900913(3857) and visa versa. This calculation cannot be used for length measurements because of high error margin.

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