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There are two answers on this question: Point is lying under the line if the line is Geodesic (which means the shortest) Point is lying over the line if the line is "on axis" line Taking in consideration that in MongoDB (2dsphere) polygons is completed using geodesics - point is in R2 and missing in R1.


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Check out this function, provided by Openlayers: getFormmatedLonLat function, in the Openlayers.Utils object. An use example: var ns = OpenLayers.Util.getFormattedLonLat(point.lat, 'lat', 'dms'); var ew = OpenLayers.Util.getFormattedLonLat(point.lon, 'lon', 'dms'); The output must be a string like: Xº Y' Z'' for each coordinate.


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Converting geographic (latitude-longitude) coordinates to plane (X-Y or row-column) coordinates is a matter of map projection. Your main constraint is probably the projection which is already being used to map the other features (runways, terminals, etc). That is, if they are already recorded/stored/displayed in some flat X-Y system, then you need to ...


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There does not seem to be any limitations measuring across the antimeridian with this library: library(geosphere) # small distance across the antimeridian distVincentyEllipsoid(c(-179.999, 0), c(179.999, 0)) # 222.639 # this should be zero, but tiny errors have entered in the maths distVincentyEllipsoid(c(-180, 0), c(180, 0)) # 1.556904e-09 And if you ...


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As @radouxju says, you have two components of a 3d cartesian conversion. It sounds like you are really looking for a Map Projection. This converts the surface of the Earth (latitude, longitude) into flat 2d cartesian coordinates. It is impossible to do this without some distortion. Hence there are literally thousands of possible projections. You choose the ...


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the two equations that you are using here are for the conversion to a 3D cartesian coordinate system (for a 3D plot with the origin at the center of the Earth), so you must have the Z-axis, otherwise you will represent the projection of your points on the equatorial plane (which is probably not what you want). public static double GetZCoord(double lat, ...


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Since you are using Node.js, you can use the Node.js module for GDAL. Get country outlines (e.g. GSHHS data set from here). Then simply script a point in a polygon algorithm using GDAL (several approaches are possible but a simple one is to test for an intersect between your point and the appropriate country polygon).


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If you know postgis, you can create the shortest line between two geometries : http://postgis.net/docs/manual-2.1/ST_ShortestLine.html. Then you can calculate the length with :http://postgis.net/docs/manual-2.1/ST_Length.html If you dont need to create the line : st_distance should be enough : http://postgis.net/docs/manual-2.1/ST_Distance.html


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Thanks to your good description I guessed that the projection that Hummingbird is using is "WGS 84 / World Mercator" which has EPSG-code EPSG:3395. More information about this projection: http://spatialreference.org/ref/epsg/3395/ http://epsg.io/3395 ...


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A simple search with Google threw up this website... http://jgiesen.de/elevazmoon/basics/index.htm



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