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springmeyer/gist:1168887

Created August 24, 2011 19:03
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gistfile1.txt
var wgs2merc = function(lon,lat) {
lon = parseFloat(lon);
lat = parseFloat(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];
}
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springmeyer commented Apr 17, 2012

sure, parseFloat sounds good.

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springmeyer commented Apr 17, 2012

also, heads up that mapnik's proj.forward may not be fully reliable. Ideally you should use mapnik's ProjTransform.forward not Projection.forward. Only the latter however is currently exposed in node-mapnik. I need to expose the ProjTransform. The problem with Projection.forward is that is makes assumptions about the source projection that may not be as robust as setting up the from->to relationship that is done in ProjTransform.

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springmeyer commented Apr 17, 2012

I'll knock out getting this exposed now: mapnik/node-mapnik#57

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