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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Discrepancies in EPSG:3857 Spherical/Web Mercator World bounds
This Question Spherical Mercator - World bounds
is answered by this Answer,
which cites https://epsg.io/3857 with the following bounds:
xmin: -20037508.3427892,
ymin: -20037508.3427892,
xmax: 20037508....
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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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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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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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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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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 ...
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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 ...
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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....
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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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Mercator: scale factor is changed along the meridians as a function of latitude?
"In Mercator projection the scale factor is changed along the
meridians as a function of latitude"
How to calculate the Mercator scale factor as a function of the latitude in decimal degrees ?
I ...
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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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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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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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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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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; ...
CommunityBot
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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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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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Mercator projection: formula for latitude based on pixels?
I am basing this question on knowledge from Mercator projection: problem with latitude formula
In that question/answer, the formula is given for working out how many pixels above/below the equator a ...
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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):
...
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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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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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Reprojecting xy tiles from mercator to Gauß-Krueger in ubuntu terminal?
I have exported a map from tilemill as mbtiles and converted them to xyz tiles with help of mbutil. The tiles should be used (for learning purpose) with mod_tile or GeoServer and displayed in ...
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Converting mercator meters without UTM zone?
I've been attempting to extract track information from Humminbird (Side Imaging Sonar) binary files and have hit a stumbling block with the coordinates it provides. The values are apparently in ...
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Improving accuracy of mercator meters conversion to lat/lon?
My question is an extention to Converting mercator meters without UTM zone?
While the answer in the previous Q&A got me so far, I've now come to an impass. While the conversion I do from Mercator ...
CommunityBot
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Transforming lat and long to Mercator x and y
I've been trying to plot a set of lat and long coordinates to a Mercator map using the following set of equations:
x = long - long0
y = ln(tan(pi/4 + lat/2))
These equations are from a page on ...
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answers
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Calculating Mercator coordinates from lat/lon
I am new to GIS but I am working on a project mapping a building using floor plans and JOSM.
Using the PicLayer plugin I added the .png floor plan as a layer.
I wrote a .cal file to set the scale, ...
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Calculating planar distance based on point coordinate and geodetic distance?
Using ThinkGeo, I have a Lat/Lon coordinate, and a distance of .1 miles. The .1 miles represents the radius of a circle and I'm trying to draw this radius around the lat/lon coordinate.
The map units ...
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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 ...
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Adding additional geometry column in PostGIS?
I'm importing many sets of geodata into PostGIS, and they have different SRID's. (Some have EPSG:3857, some EPSG:4326, some something else).
I'd like to create an additional geometry column, eg. ...
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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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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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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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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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Re-projecting from Polar projection to EPSG:4326?
I simply want to project a polar stereographic raster (EPSG:3411) to Mercator (EPSG:3857) or WGS84 (EPSG:4326). The data I is from NOAA.
$gdalwarp -s_srs EPSG:3411 -t_srs EPSG:3857 northpsg.20141027 ...
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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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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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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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Flat Map that can go thru North Pole
Is there any map SDK or tool that can show the navigation that passes through the north pole in a flat way? Basically If I use a Mercator projection map it is only flat and cannot show the north part ...
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Calculating distance scale factor by latitude for Mercator
This was really inconvenient topic to google out - so I'm asking for clarification, did I understood things correctly.
I'm talking about measuring short distances in Mercator projection (3857). You ...
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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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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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