[PROJ] WGS84(Natural Earth data) to sphere

[Gonzo Bard]

> Why do you want to convert the points to an sphere? GeoJSON is also
defined in WGS84

GeoJSON data is rendered in the browser using projections:
Web Mercator - https://github.com/d3/d3-geo#geoMercator
Stereographic North - https://github.com/d3/d3-geo#geoStereographic
According to the developer of the projection engine, it is expected that
geographic points transferred to the projection lie on a sphere:
https://github.com/d3/d3-geo/issues/265#issuecomment-1234323369

On the other hand, the data I want to place on the map is only prepared
under the assumption that the planet is a spheroid.

Based on NGA research:
https://web.archive.org/web/20141009142830/http://earth-info.nga.mil/GandG/wgs84/web_mercator/(U)%20NGA_SIG_0011_1.0.0_WEBMERC.pdf
see Figure A1 – Latitude versus Absolute Projection Difference (in
kilometers)
I came to the conclusion that the users of my application can be
significantly misled (up to several tens of kilometers).

чт, 10 нояб. 2022 г. в 18:11, Javier Jimenez Shaw <j1 at jimenezshaw.com>:

> Why do you want to convert the points to an sphere? GeoJSON is also
> defined in WGS84
> .___ ._ ..._ .. . ._.  .___ .. __ . _. . __..  ... .... ._ .__
> Entre dos pensamientos racionales
> hay infinitos pensamientos irracionales.
>
>
>
> On Thu, 10 Nov 2022 at 11:24, Gonzo Bard <gonzo.bard at gmail.com> wrote:
>
>> Greetings to all!
>>
>> I use Natural Earth data:  https://www.naturalearthdata.com/downloads/
>> > All Natural Earth data use the Geographic coordinate system
>> (projection), WGS84 datum
>> That is, Natural Earth data are points on an ellipsoid.
>>
>> To display geographical data on the map, I pre-convert it from Shapefile
>> to GeoJSON.
>> To do this, I use the ogr2ogr program (GDAL library).
>> In ogr2ogr there are conversion options:
>> from -s_srs
>> https://gdal.org/programs/ogr2ogr.html#cmdoption-ogr2ogr-s_srs
>> to -t_srs https://gdal.org/programs/ogr2ogr.html#cmdoption-ogr2ogr-t_srs.
>>
>> If I understood correctly, the GDAL project uses OSGeo / PROJ as a
>> projection library.
>>
>> Please tell me what the values for -s_srs and -t_srs should be in order
>> to perform the conversion:
>> points located on an ellipsoid (WGS84 datum) ===> to points located on a
>> sphere?
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>> https://lists.osgeo.org/mailman/listinfo/proj
>>
>
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