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With GDAL and other Proj4 based programs it is handy to define the projection by its EPSG code shortcut like "epsg:28992". Shortcut is converted to actual Proj4 projection string by doing a lookup into proj installation files. Unfortunately there are lots of projections with several different projection definitions hanging aroud. Most typical case is that ...


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What I did to solve this problem was: I used the pyproj library to convert from WGS84 to Robinson as here: import pyproj crs_from = pyproj.Proj(init='EPSG:4326') crs_to = pyproj.Proj('+proj=robin +lon_0=0 +x_0=0 +y_0=0 +ellps=WGS84 +datum=WGS84 +units=m +no_defs') x, y = pyproj.transform(crs_from, crs_to, LONGITUDE HERE, LATITUDE HERE) Then I realized ...


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The base dataset is in RGB format but the issue is caused when one layer is not visible due to Min/MaxScaleDominator in the SLD. If you check the two layers individually using GDALinfo I believe you will find that the format of the blank tile has been changed by GeoServer and is now RGBA whilst the visible tile is still in the original RGB. We think it is ...


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Check if the source data uses paletted colours. You can not reproject them easily, because interpolating paletted colours will fail. Convert the source data to RGB or RGBA, and the interpolation during reprojection will deliver good looking results. Furthermore, check if NODATA value conflicts with any used colour.


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From the developers via GDAL-dev Mailing list: The issue can be solved by using -wo SAMPLE_STEPS=1000 It even works for me with a value of 500: gdalwarp -overwrite -s_srs EPSG:4326 -t_srs "+proj=natearth +wktext" -wo SAMPLE_STEPS=500 -of GTiff NE2_LR_LC.tif reprojected.tif


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I can reproduce the error with another Natural Earth image http://naciscdn.org/naturalearth/10m/raster/NE2_LR_LC.zip and GDAL version 2.0-dev. Write a mail into gdal-dev mailing list. I believe that the issue is real and you can file next a ticket into GDAL bug tracker. I also verified that problem is not caused by the lanczos resampling but "-r average" ...


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The definition for MGI_Austria_Lambert is straight from Esri software. It has several differences in naming conventions plus quirks in the projection/parameter names. Some of these date to older versions of the EPSG Geodetic Parameter Registry where Esri has not updated to match EPSG. Esri has one keyword for Lambert conformal conic and it's possible to ...


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WGS 84 is not a cartesian coordinate system. You can use it directly for your visualisation purposes, but you should be aware that distances, shapes and areas will be distorted. If you want to project your WGS 84 coordinates to a 2D cartesian reference system, you'll need to choose a destination coordinate system : there is no single answer to your ...


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follow the instructions I gave here How to reproject a vector layer in QGIS? and you are done: before: and after:


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I tried this out and had no issues... once the data was re-projected and added to the map, I re-set the map to EPSG:3857, added the Google map via OpenLayers, and the re-projected (and projected on the fly) dataset of yours worked just fine:


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Terminology By definition, the scale is the amount by which (infinitesimal) distances are multiplied by the projection. Whenever a tiny displacement of d meters on the earth is associated with a displacement of d/s meters on the map, the scale is written as 1:s. It may depend on the direction of the displacement. The scale factor compares the scale at ...


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1. Degrees to Radians: convert decimal degrees to radians, in JS: // Converts from degrees to radians. Math.radians = function (degrees) { return degrees * Math.PI / 180; }; console.log(Math.radians(45) * 4); // correctly = PI 2. Calcul of scale factor k: Then, mathematicians, who generally talk in Radians, expose : "In Mercator projection the ...


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You can do this using cartopy. #!/usr/bin/env python import cartopy import cartopy.crs as ccrs import matplotlib.pyplot as plt from pylab import imread im = imread('Robinson-projection.jpg') ax = plt.axes(projection=ccrs.Robinson()) plt.imshow(im, origin='upper', extent=[-17005833.330525, 17005833.330525, -8622512.772008, 8622512.772008], ...


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You can use the GeodeticCalculator which should be faster. Something like: package com.envitia.spike; import org.geotools.geometry.DirectPosition2D; import org.geotools.referencing.CRS; import org.geotools.referencing.GeodeticCalculator; import org.opengis.referencing.FactoryException; import org.opengis.referencing.NoSuchAuthorityCodeException; import ...


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The problem is almost certainly with the "Sphere_Mercator" data. This projected coordinate reference system (CRS) is using a sphere-based geographic CRS. ArcGIS doesn't have any predefined geographic/datum transformations that convert to or from a sphere. The data may have been built on the sphere, or it might have been built on WGS 1984 and then projected ...


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If you just want a reprojected dataset, the following libraries/Tools may help: proj4 (C++ library) provide transformation between different projections. GDAL/OGR (C++ library) provide transformation between different vector/raster format, support projection transformation if you specify compiling parameter forcing to compile with proj4 dependency. ogr2ogr ...


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I managed to get this working, and have written up the answer at: https://mapwingis.codeplex.com/discussions/560231 Here it is repeated in full: Thanks Paul, I tried a number of things, I tried reprojecting the map* on the fly, which although returned "true", and there was no error code in sf.get_ErrorMsg(sf.lastErrorCode)); - and even when ...


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It's a two-stage solution: project geo-coords (lat, lon) to a Robinson map (N, E) transform the map (N, E) to a screen window (row, col) For stage 1, projection, you can use the ogr2ogr tool. Gothos explains how to use it for Robinson in particular transform-projections-with-gdal-ogr The EPSG library is extensive, but doesn’t contain everything, ...


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If you load the South American Data into QGIS as WGS84, then Save as ... under a different name and Selected CRS EPSG:3857 World mercator, the shape will find its correct place in South America (supposed that On-the-fly-reprojection is active). In a second step, you can save the World Mercator file to jet another name and EPSG:4326, which will reproject the ...


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I posted an answer here which may help anyone who is having trouble importing/projecting CSV survey data: http://gis.stackexchange.com/a/109619/14731


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I've used this online converter successfully: http://converter.mygeodata.eu/vector


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You do not need to re-project your shapefile in Arc Map (Tilemill will do it). Instead, when you add your layer in Tilemill you have to select Custom for SRS and enter the complete datum of your shapefile.



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