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.
84
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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 ...
- 469
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0
answers
53
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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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1
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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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0
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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 ...
- 21
3
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1
answer
454
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Convert a point on a flat 2D web-mercator map image to a Coordinate
I have an image of a map and a point marked onto it. I have those coordinates (as a percentage) inside the image of the point. Now I'd like to know the coordinate (latitude/longitude) that this point ...
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2
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1
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437
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Convert image from EPSG:4326 to EPSG:3857
I'm new to GDAL and map projections, I need to convert equirectangular (EPSG:4326?) projection to "pseudo Mercator" (EPSG:3857?) projection used by 90% web-based maps (which is simple this 0/...
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0
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49
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Size of area in Web Mercator
I downloaded a satellite image from Sentinel Hub. I requested a 10,000 x 10,000m image in Web Mercator (EPSG:3857).
Here is a piece of code that I use:
bbox = BBox(bbox=[x, y, x + 10000, y + 10000], ...
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0
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0
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126
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Error in WGS84 to Mercator coordinate transformation
I'm trying to convert the (lat,lon) of WGS84 into Mercator (x,y). Below I've listed all the relevant information given in the file.
Datum="WGS84"
Ellipsoid="WGS84"
...
0
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0
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51
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Negative latitude after calculating position from tile name
I am using Geoserver to generate tiles and I want to get Lat/Lon from tile file name. I use the following functions from (https://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#ECMAScript_(...
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59
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Cache feature lengths are in Web Mercator, what is the conversion factor to miles?
I have a cache polyline feature with a Shape_Length field calculated in Web Mercator. I need to convert that feature length to feet or miles. I am using the Value Conversion tool in Dashboards !!...
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2
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61
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Dynamically build quadtiles compatible with spherical Mercator (mathematics)
I have a spherical Mercator map in degrees coordinates (-180, -85, 180, 85) programmed.
I add points to it one-by-one, and on some condition (ex, there are more than 25 points on map), I split this ...
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1
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640
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Is OpenStreetMaps's Nominatim "Centre Point" the centroid and what EPSG is it?
I looked up a couple of places on OpenStreetMap's Nominatim, like Bruck an der Mur, and I could not confirm whether the reported coordinates are indeed the same thing as the centroid, and which EPSG ...
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0
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Does setting appropriate SRID make diffrence to rendering peformance?
I understand that PostGIS allows us to set SRID on geometry or geography.
But I am just wondering if it would actually impact the rendering performance on the client side.
For instance, let's say I ...
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0
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0
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597
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Adding metre distances to Web Mercator projection
I'm new to using GPS and using map projections. I've read quite a bit but I'm struggling to understand how to use Web Mercator projection.
I have lat/long coordinates from the nuScenes dataset. The ...
5
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1
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302
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TMS tilenames for Elliptical Mercator projection - EPSG:3395
My goal is to derive TMS tile names from given lat/lon and vice versa for Elliptical Mercator projection (EPSG:3395) using Python.
OSM wiki explains the logic for Spherical Mercator (EPSG:3857), but ...
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1
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572
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Generate polygon shaped as a circle if projected using Web Mercator, in Python?
I need to solve problem very similar to Generating polygon representing rough 100km circle around latitude/longitude point using Python? but subtly different.
I need a shape that will be a circle once ...
4
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1
answer
506
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Reproject EPSG:3857 to Gnomonic projection using GDAL
I'm trying to reproject Mapbox maps from whatever projection they come in (which I believe is EPSG:3857) to what I believe should be a Gnomonic projection.
Let me try to be more clear actually. I'd ...
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0
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1
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180
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Get UTM regions overlapping with a geojson polygon
how can I get the list of UTM grids overlapping with a geojson polygon in web mercator? I am trying to download data off of Sentinel, and I am seeing if I can go directly from an input polygon to ...
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2
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0
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Meaning of statement in GRASS r.horizon manual
I have a question about this statement in the r.horizon manual:
"If your projection is based on distance (easting and northing), these
too must be in meters. The buffer parameters must be in the ...
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2
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1
answer
133
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Fixing misshaped GeoJSON polygons [closed]
In 2018 Ghana changed its administrative divisions (from 11 to 16 regions, and from 216 to 260 districts). Unfortunately, I have not been able to find the GeoJSON (or equivalent) data for the new ...
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1
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1
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402
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How to transform Google/OpenStreetMap Co-ordinates to ESPG:3857 Co-ordinates?
I have an old map successfully layered on OpenStreetMap on QGIS and have been able to add delineated text points from a CSV file using WGS 84 / Pseudo-Mercator ESPG:3857 co-ordinates.
I have tried ...
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0
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2
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876
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Using WGS 84 (SRID 4326) or Web Mercator (SRID 3857) [closed]
I'm new to GIS and learning about SRIDs.
Are there still other relevant or commonly used SRIDs than WGS 84 (SRID 4326) or Web Mercator (SRID 3857)?
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0
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152
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How to project an image with gdalwarp to cover a Mapbox map?
I'm trying to re-project a geographical raster source covering entire world (temperature data from GFS) to Web Mercator with this command:
gdalwarp -t_srs EPSG:3857 input.grib output.tif
However, ...
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0
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1
answer
891
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Convert pixel x,y position on map to latitude and longitude
My map takes up 100% width and height of the browser screen.. I have a draggable div that is super imposed over the map, I am am capturing this divs position using offset(); to get the pixel top and ...
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0
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99
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proj.4 — problems to understanding the projection result
I am using pro4js for a webproject to project data obtained from the Openstreetmap database. Basically I have this code (javascript/ES 6):
const
//some coordinates
we = {
lon: 50.9802813,
...
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0
votes
1
answer
639
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Reproject Geoserver layer in Web Mercator Mapbox frontend
I am looking to visualise live satellite imagery in a Mapbox GL JS Fronend. There exists a Geoserver instance which has exactly the resource I want to use. However, the layer is in the wrong EPSG. ...
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0
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203
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Changing Map Coordinate System Changes in ArcGIS Pro Changes Azimuth
I am trying to create a label that will overlay a line in ArcGIS Pro, the layer is coming from a PostGIS database. The underlying materialized view for the label/symbol overlay is something like this: ...
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182
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Normalize OSM geometry to 1x1 coordinate system
I'm extracting a couple of geometries with overpass turbo and need to "normalize" their shape from lat-lon to [[0-1][0-1]] coordinates.
The first thing I've tried is probably pretty wrong: get ...
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2
answers
2k
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Computing distance between two spherical Mercator points
I am computing the Mercator points according to the top answer at Convert latitude/longitude point to a pixels (x,y) on Mercator projection.
Now that I have two Mercator points on a spherical ...
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2
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385
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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 ...
2
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1
answer
344
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GDALWARP cuts off right edge of image?
I'm reprojecting GFS GRIB files to EPSG:3857 using gdalwarp. Resulting file get little bit shorter to the right so when I zoom in from zoom level 5 and higher, I can see vertical line with missing ...
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Converting a pixel coordinate in GeoTIFF to a latitude and longitude?
I have a GeoTIFF with the following meta information:
PROJCS["WGS 84 / Pseudo-Mercator",
GEOGCS["WGS 84",
DATUM["WGS_1984",
SPHEROID["WGS 84",6378137,298.257223563,
...
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1
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609
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Differences in angle measurements in Web Mercator
I am trying to measure different angles on 2D map using lat/lon coordinates taken from Google Maps, and Java library JTS.
I have noticed a weird thing: my measurements are always distorted, except ...
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0
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254
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Converting latitude/longitude to full range referential
I have a list of latitudes and longitudes expressed as follow:
-1 <= latitude <= 0
0 <= longitude <= 1
Those coordinates represent POIs on a fantasy map displayed using the Leaflet ...
- 111
0
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0
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146
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Projecting EUMETSAT precipitation data
I downloaded the H05 – PR-OBS-5 Accumulated precipitation at ground data from H-SAF. The Product User Manual states the dataset is in rectangular stereographic projection centred on 42°N, 10°E. I need ...
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Why don't public organizations support Web Mercator EPSG 3857 for WMS? [closed]
Given that Web Mercator is the defacto standard for web mapping and all basemaps (Google, ESRI, Mapbox) are based on this coordinate system..
Why do many organizations e.g. NOAA not publish their WMS ...
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2
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2k
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MapBox or Google Maps Static API: Extent or bounding box of image?
I'm using the MapBox or Google Maps Static API to get map images. I understand that the centre of the image is specified in terms of latitude and longitude, but is there any way to either specify or ...
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1
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1k
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Open Basemap in different Projection (Transverse Mercator) - QGIS
I have data in a transverse Mercator projection which is a different projection from my base map (Spherical Mercator / Web Mercator / pseudo-Mercator). I really would like to create a map in a TM ...
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293
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Difference in Spherical Mercator(google/mapbox/supercluster code) calculation and Postgis 3857
As per source code of supercluster, google map utils and mapbox formula to convert (lng, lat) to spherical mercator is as
x = lng/360 + 0.5;
siny = Math.sin(Math.toRadians(lat));
y = 0.5 * Math.log((...
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Reprojecting from MODIS Sinusoidal to Web Mercator: how to calculate output raster dimensions?
I have a MODIS image from AWS in sinusoidal projection and I want to calculate output raster size after reprojecting it into Web Mercator (EPSG:3857).
$ gdalinfo MCD43A4.A2017185.h11v03.006....
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Convert GPS coordinates to Web Mercator EPSG:3857 using python/pyproj
I've created a couple of functions using the math package from python 3.5 to transform GPS coordinates to x/y web mercator (pseudo mercator) as explained here: http://wiki.openstreetmap.org/wiki/...
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satellite imagery basemap for webmapping application
I am currently trying to develop a small webmapping application to show some point data which covers the whole planet.
I do want to use projections different from webmercator, like Robinson ...
user52883
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2
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389
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Problem aligning points near North Pole using Web Mercator with QGIS and Google Street View
This is my first time using QGIS 2.18.
I created a project with EPSG:3857.
Added OpenLayers Plug-in to use Google Street View as a map for the points and data I want to work on.
I love self-...
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2
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2k
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Convert UTM to Web Mercator
I'm looking to programmatically convert UTM to Web Mercator (a.k.a. Spherical Mercator, EPSG:3857, EPSG:3785, OpenLayers:900913). I'm looking for the algorithm, or something that runs on iOS (Swift, ...
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4
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Understanding strange measure distance results from QGIS?
My colleague just told me about incorrect measure distance tool results in QGIS. For reference we used this pond.
While our local map provider Mapy.cz
and Google Maps:
both show about 970 meters ...
- 1,728
4
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0
answers
5k
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Converting lat/long to EPSG:3857 coordinates
The map widget I'm using gives me click locations in lat/long. I need to convert those coordinates to EPSG:3857 to query a database.
Most of the solutions I've found use the formula described in ...
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1
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6k
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How do I convert tile pixels to longitude and latitude for web mercator?
I need a function to convert from tile pixels (x, y) from the Web Mercator projection (aka EPSG::3857 or SRID 900913), to longitude and latitude.
I'd like the function to be written in pseudo-code or ...
- 517
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1
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3k
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Project from GCS_WGS_1984 to WGS_1984_Web_Mercator_Auxiliary_Sphere
What is the default transformation method to project data from from GCS_WGS_1984(WIKI 4326) to WGS_1984_Web_Mercator_Auxiliary_Sphere(WIKI 3857)?
ArcMap 10.3.1
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1
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1k
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Command line tool for reading .shp, .prj and converting to Google Maps lat lngs
I have a data file exported from an ARCGIS system (parcel data from local government). Its a zip file containing 7 files: f.dbf, f.prj, f.sbn, f.sbx, f.shp, f.shp.xml, f.shx.
I have a simple ruby ...
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0
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829
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Transform projection with SharpMap
I have SharpMap loading a shapefile and displaying the rendered image to a PictureBox.
If I open the shapefile in QGis I can see the SRC:
+proj=merc +lon_0=100 +lat_ts=-41 +x_0=0 +y_0=0 +datum=...
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