Questions tagged [web-mercator]
Web Mercator a.k.a WGS 84 / Pseudo-Mercator -- Spherical Mercator, is a projected coordinate system used for rendering web maps in applications like Google Maps and OpenStreetMap. The area of use is limited to World maps between 85.06°S and 85.06°N.
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How to reproject TIFFs to COGs and have TILING_SCHEME info in the output files when using GDAL?
Issue presented using GDAL called from Python
I have a TIFF file, src.tiff. I want to reproject it and create a COG, dst.tiff. To achieve that, I do the following:
from osgeo import gdal
warp_opts = ...
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Why do large radius circles on Google Maps turn into sine waves?
I'm interested in building a world map display of sunrise/sunset times without Google Maps.
Existing models like https://github.com/rossengeorgiev/nite-overlay use google.maps.Circle instances with ...
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How compass bearings map to a Web Mercator projection
I'm trying to figure how compass bearings map onto a Web Mercator projected map, so I can draw a line in a specific bearing. Magnetic declination needs to be taken into account, but since in Web ...
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Trying to configure reprojection of Tile Source to Web Mercator using Mapproxy
I have a source of tiles served from a WMTS, these tiles are cached in a proprietary scale format and is not following any of the standards as GLOBAL_WEBMERCATOR.
I have a client that wants to fetch ...
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Pulkovo / Stereo 80 to Mercator conversion
I wanted to overlay layer of vector tiles build in Stereo 80 (Pulkovo) over the ArcGIS map.
Because I cannot do it on the fly I was trying to convert it using a few CLI tools ... my code looks as ...
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latitude_of_origin not working for Web Mercator image
I'm trying to use geotools to render a Web Mercator GeoTIFF of the United States under a shapefile, using this projection for the GeoTIFF:
PROJCS["WGS 84 / Pseudo-Mercator",
GEOGCS["...
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Web Mercator 3857 and shapefiles in other projections
I'm struggling to understand how Web mercator EPSG 3857 Projected Coordinate System WGS 1984 works. By default, in ArcGIS Pro, all base maps are provided in EPSG 3857, and when I create a new project ...
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Calculating bounds for slippy tile
Have noticed a great number of libraries that calculate the bounds for a tile like so:
def TileBounds(self, tx, ty, zoom):
"Returns bounds of the given tile in EPSG:900913 coordinates"
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Using MapProxy to create slippy map tiles with EPSG:25833 supporting WMTS endpoint
The Norwegian section of the JOSM basemap list mentions the NPI Svalbard Orthophoto basemap. It is a WMTS endpoint serving orthophotos tiled using EPSG:25833.
I would like to have an endpoint which ...
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Is azimuth preserved in EPSG:3857?
I am trying to draw the outlines of drone images using OpenLayers. The drone has recorded a "yaw degree", which should be the azimuth. However, when I place the rectangles on the map, their ...
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ST_OrientedEvelope returning parallelogram instead of rectangle
I have a GIS application with multiple polygons where I'd like to get the bounding box of the polygons.
The ST_Envelope function works as expected. Because the map is rotated the polygons always ...
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Converting Mercator tile coordinate to an OL TileGrid coordinate in OpenLayers?
Is there a method to convert the normal {z}/{x}/{y} endpoints you would get from a tile service into an OpenLayers TileGrid tile?
Here is a mercator tile with coords:
However in OpenLayers the ...
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The true size of something when 'on the fly' moving around in EPSG:3857
I know this should be a trivial question, but I still will ask it as I have a knot it my head...
The Web Mercator is distorting shapes and areas further from the equator. This is why Greenland is so ...
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If a scale bar measures incorrectly in the web mercator projection, how can it be correct in Google Maps?
I've started to read a bit more into coordinate systems, projections and the problems around them and so far I understand that in the WGS 1984 Web Mercator (auxilliary sphere) coordinate system a ...
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GeoServer doesnt generate tiles for EPSG:3857 grid
I failing to generate .geojson tiles with GeoServer for grid with EPSG:3857 projection.
Note that it successfully generate .png tiles with the same config, and also .geojson generation works for other ...
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