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2 questions: "confusion about EPSG:900913" and "performance of Equirectangular projection" #49
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since epsg:3857 cuts the map at +-85° latitude, im kinda confused about the projected coordinates, i guess that is why people had problems with extremely distorted poles. right now i use +-19949545.833216466 as boundary, but thats not really relating to 40030/2 (Earth's circumference/2). 19949545.833216466 derived from datumstospherical-boundaries with mapscale=Earth's circumference*10^x |
ok i get it now, the epsg guys refused to give it a valid epsg number: |
so is it possible to use Equirectangular projection for planes? |
Equirectangular projection
wouldnt it be better for planar projection/map to use Equirectangular coordinates:? this could even spare unnesscesary computation in spherical mode with a increased zoom/low fov by switching to planatary.
by switching to non-spherical coordinates i dont need to to convert and remap/interpolate the spherical coordinates for every single vertex of every element that i want to place/find on the planatary map.
->
"x = r λ cos(φ0)
y = r φ
This is simple equirectangular projection.In most cases, you'll be able to compute cos(φ0) only once, which makes subsequent computations of large numbers of points really cheap."
EPSG:900913
i guess you relate to EPSG4326:
"There are a few things that you are mixing up.
Google Earth is in a Geographic coordinate system with the wgs84 datum. (EPSG: 4326)
Google Maps is in a projected coordinate system that is based on the wgs84 datum. (EPSG 3857)
The data in Open Street Map database is stored in a gcs with units decimal degrees & datum of wgs84. (EPSG: 4326)
my problem is that 900913 is actually not listed on https://spatialreference.org/ ->** can be used to generate proj4 reference code like https://spatialreference.org/ref/sr-org/7483/proj4/ for absolute accurate coord.-to-cartesian-converion**
thanks again for the project. its really great!! im having problems with spherical geometry in react-fiber though...planning to publish a react-preset, but spherical, is just not working... anyway thanks for support!- leo
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