# Questions tagged [mercator]

The Mercator projection is a cylindrical map projection presented by the Flemish geographer and cartographer Gerardus Mercator in 1569.

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### Mercator CRS that covers the extent -90,-180 to 90,180

Is there a EPSG CRS for Mercator that isn't deprecated and covers -90.0,-180.0 to 90.0,180.0?
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### Hotine Oblique Mercator projection Where is the code in C/C++/Python?

For these functions: SetHOM() Set a Hotine Oblique Mercator projection using azimuth angle. SetHOM2PNO() Set a Hotine Oblique Mercator projection using two points on projection centerline. SetHOMAC() ...
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### Converting latLng to screen point

I have a map in RN app on iOS and I have and overlay outside of the map Inside overlay I need to draw a View with some absolute position that will match some LatLng coords on the map I know screen ...
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### Make very detailed SVG map of world country borders and administrative objects

I need very detailed map for my project, in Mercator projection. I tried to find downloadable resources, even not free, but all that I have found is in very bad resolution. I need as much detailed ...
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### Transform coordinates to WMTS tiles in EPSG:4362 [duplicate]

How can I calculate the tiles numbers/names in EPSG:4362 based on lat, lon and zoom ? Note that I was able to do it for EPSG:3857 Pseudo-Mercator, but the formula in wikipedia and the one in here ...
1 vote
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### Map projection from latitude/longitude to cylindrical system [closed]

I have some questions about projections. First of all, I would like to plot some positions on a x-y grid, graduated in km from latitude/longitudes coordinates. Is this conversion relevant: https://en....
1 vote
485 views

### Identifying the EPSG code for projection

I'm trying to convert a dataset that has projection parameters in meters to lat/long coordinates. After researching online and on stack exchange, I came up with a code. I used the input EPSG as 3857 ...
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### Why does the calculation for y-value (when converting from lat/long to a Mercator x,y) involve the width of the map?

I have been looking into converting latitude and longitude into x and y coordinates. This link (first answer) provides a perfect answer for me, but I am wondering why it works. I have figured out why ...
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### Create true length scalebar for different latitudes with QGIS geometry generator in Mercator projection

In Mercator projection, distances are heavily distorted, the closer you get to the poles. True distances can only be measured only on the equator. The distortion is constant along parallels - so e.g. ...
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### How Mercator projection works

I found this web page that explains how Mercator projection works : https://personal.math.ubc.ca/~israel/m103/mercator/mercator.html In the section "How to do it", I didn't understand this ...
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### Order of latitude and longitude in EPSG:4326

I recently started working with GPS data in PostGIS and am very confused about the order of latitude and longitude. I'm from Europe, and here everyone I know uses latitude first, longitude second, e.g....
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### Use ST_DWithin on WGS84 geometry data

I've just used osm2pgsql to import osm data to a PostGIS database, using lat/long option to store it in WGS84 projection. I would like to use ST_DWithin to select nodes close to a random point. When I ...
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### Mercator vs Lambert Conic Conformal Projection

I am using coordinates in WGS 84 (coordinate reference system EPSG:4326). Unfortunately I am not very familiar with the different projections and currently do not see the wood for the trees. Is EPSG:...
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1 vote
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### What does the coordinate values represent when using WGS 84 / Pseudo-Mercator (EPSG:3857)?

I have been using QGIS for a couple of weeks now, mostly for data collection in my research project. Currently, I'm trying to plot these points, in a graph similar to this one (but in kilometers), I ...
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1 vote
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### How to "unravel" a polar continent (i.e. Antarctica) from azimuthal projection and convert it into equirectangular?

I have very recently gotten into cartography and map projection, and I wanted to visualise the map from Avatar: The Last Airbender into a proper equirectangular map. Here is the map for those ...
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### Meridian Convergence in UTM and Gauss Kruger Projection system?

There are points where geographic coordinates (latitude and longitude) are known. I have calculated the UTM (Universal Transverse Mercator) projection coordinates of these points and then I want to ...
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### Calculating latitude from X,Y-coordinates on Mercator projection

I have a task to create a map of a specified section of the world. In particular, I need to map everything between the 120E and 100W longitudes and everything between the 60S and 30N latitudes mapped (...
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### GeoJSON coordinates transformation to Web Mercator coordinates

I'm not sure how OpenLayers is converting the raw coordinates from a GeoJSON's geometry.coordinates property into a Feature's extent property. I can't really seem to find a lot of documentation on it ...
1 vote
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### QGIS buffer distance parameter

This is very intriging, I don't remember having seen this before. I am working with the Vector -> Geoprocessing Tools -> Buffer tool in QGIS (2.8.6-Wien) If operating in British National Grid ...
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### Satellites GOES16 and 17 - reprojection to Mercator is stretched

I have downloaded GEOS data from https://cdn.star.nesdis.noaa.gov/GOES16/ABI/FD/ (or https://cdn.star.nesdis.noaa.gov/GOES17/ABI/FD/). I want to reproject the disk to Mercator projection. I have used ...
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1 vote
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### Transform equirectangular simple TIFF to Mercator projection with gdal_translate / gdalwarp

I'm trying to transform this shaded map of Venus, a 2000x1000 TIFF in what I believe is equirectangular projection, without GIS metadata, to Mercator. I first tried gdalwarp -s_srs EPSG:4326 -t_srs ...
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1 vote
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### Distance difference when moving longitude in maps services [closed]

I try to get two juxtaposed tiles in maps services like Google Maps or Bing Maps at a given zoom level (20 in my case). I managed to do it with those methods: def meters_per_pixel_NS(lat, zoom): ...
1 vote
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### Optimizing projection for accuracy in calculating distances

I receive a set of LatLong points and I want to optimize the projection to Euclidean points so as to try to keep (distance in Euclidean space)/(greater circle distance in latLong) with variance as low ...
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### Generate EPSG:4326 Vector Tiles

My goal is to create EPSG:4326 vector tiles (using Plate Caree) that can be served in Leaflet. I currently have a .shp file, which I converted to a geojson file using ogr2ogr. The main obstacle to ...
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1 vote
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### Converting X and Y coordinates from Mercator world map (square) image to Latitude and Longitude

I'm using the following JS to transform Latitude and Longitude to X and Y coordinates but now I need the contrary, transforming Latitude and Longitude to X and Y. export const latLon2xy = (lat, lon, ...
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### Converting between coordinate systems but retain visual shape? [closed]

We have some data that is stored in GeoJSON format (using EPSG:4326), but now we want to display the data in the mapbox-gl-js, which only supports EPSG:3857 for display (support for other projections ...
2k views

### Using project / layer CRS in QGIS?

I'm using QGIS 3.4.1, and I'm trying to print 61km x 61km area map of somewhere South Korea. Then I need to send this map with west / east latitude and north / south longitude info to other person, ...
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### Regular grid for whole planet

I`m trying to generate rectangular grid for whole world with fixed cell size in 350 meters (width and height are equals). What i tried to do: 1) in main loop iterate trough longitude in range [-180; ...
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### Mercator map coordinates transformation formula

I have a third-party application with a city map of size 131072x131072. There are data on this map which contains x and y coordinates. I want to transform these coordinates to latitude and ...
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### Angular rotation using Proj4, for local coordinate system

I have a polygon feature on map to which I need to transform the coordinates to local coordinate system with respect to new origin while keeping the same datum. So far using the Proj4 library and by ...
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1 vote
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### Map camera image onto sphere

How would I determine what the red point (phi', theta') is for a camera oriented at a known (phi, theta) is from a given image? The point of this is to determine what (dphi, dtheta) is so that I can ...
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### Calculate Latitude based on a mouse position on Mercator map

I have a similar question to the one found here, Mercator projection: formula for latitude based on pixels? The answer was very helpful but my question is just different enough that it doesn't quite ...
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1 vote
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### Straight lines plotting as curves

I'm trying to do something really simple, plot a rectangle using psxy on a .cdf grid file. Something like: grdimage grid.cdf -JM20c -R-70/0/20/60 -Bf20g10 -K > image.ps psxy rectangle.dat -JM -R -B -...
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### C# - convert lat long coordinates to WKT format

How can I convert coordinates to WKT format like 39.8251136,-8.3824103 with 900913 system (spherical Mercator)? My client is askying me something like this: SRID=900913;POINT(-939520.0088637 4744291....
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### Mercator - create uniformly distributed dots over map

I have a map in Mercator projection. I know coordinates of corners. I want to render uniformly distributed dots to map. for (float latDeg = startLatDeg; latDeg <= endLatDeg; latDeg += stepLatDeg){ ...
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### Problem with parseWKT : projection mercator-2SP

1 -CoordinateReferenceSystem crss = CRS.parseWKT("PROJCS[\"Mercator\",GEOGCS[\"WGS 84\",DATUM[\"WGS_1984\"," + "SPHEROID[\"WGS 84\",6378137,298.257223563,AUTHORITY[\"EPSG\",\"7030\"]]," ...
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### Why maps package adding straight lines in North America using mercator projection in r?

Why is this code creating a bunch of lines crossing the map? map(database = "world", proj="mercator", fill=FALSE, bg="white", resolution=0) How can I remove it without changing the ...
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### problem converting OTF from Mercator to equal area

QGIS 1.8.0 on OSX 10.10.5: I've got continent outlines from Natural Earth that are in EPSG:4326 (degrees) plus USGS tree range data in EPSG:2030 (also degrees). When I set the project CRS to EPSG:4326 ...
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### Converting EPSG to D3.js

Given an EPSG projection (say, this Alabama one: http://spatialreference.org/ref/epsg/26729/) How can you take the given WGS84 projection bounds in such a way that you can use them in a D3.js ...
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### Convert lat/lon to Mercator x/y, then measure distance

I'm attempting to convert latitude/longitude coordinates to X/Y coordinates on a 52,000 sq. ft. grid according to a simple Mercator projection. I used the following Python code to accomplish this, ...
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### a localised 2D coordinate system from GPS coordinates

I spend a few days reading about coordinate systems, map projections, datums, etc. Since I am new to gis, I am not confident I am doing this right. Problem at hand: I have a GPS device that gives ...
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### Generating perfect tile set from Mapbox for given zoom level?

I'm using Mapbox API to generate bitmap tiles. First of all I have generated whole world tile with zoom 1 (seems it doesn't matter 0 or 1) and resolution 1280x1280. This tile perfectly positioned from ...
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### gdal2tiles pixel shift in output tiles

I would like to re-calculate large geotiff files (10,000 x 10,000px) with the help of gdal2tiles into little (256 x 256px) tiles. The process works fine. However, the result is not perfect. There is ...
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### Using pyproj and Mercator: x_0=0 and y_0=0?

I'm having a hard time figuring out how to project correctly from a Mercator projection to LAT/Lon. Basically, I have a netCDF file with the following variables: LON0 = 42.0 => reference longitude ...
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### How does what3words build a grid of squares on the surface of the Earth?

What3words built a grid of squares of 3m2 on the earth. Does anyone know what is the algorithm ? I started with this method: the range of longitude is [-180, 180] and the range of latitude is [-90,90]...
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### How a draw a circle (on the surface of earth) on a mercator projection?

I would like to use R and leaflet to draw a circle (a real circle on the surface of the earth) on a mercator projection. In the following code, I have the center of the circle (with lng=0 and lat=60),...
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### QGIS Qtiles from EPSG 3395

I am having issues while converting my layer from 4326 to 3395. My Qtiles does not make tiles. I have a source mapinfo in 4326 with long, lat pairs. My goal is to show this on a maps.yandex (3395 ...
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### What's the accuracy of Web Mercator EPSG:3857?

Are there any references on the accuracy or (min/max/avg) error of Web Mercator when it comes to e.g. distance calculations? For the sake of completeness, I haven't found any reference to the ...
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