Antimeridian Cutting for Bounding Boxes
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trasch commented
From the specification: https://tools.ietf.org/html/rfc7946
- Bounding Box
Example of a 3D bbox member with a depth of 100 meters:
{
"type": "FeatureCollection",
"bbox": [100.0, 0.0, -100.0, 105.0, 1.0, 0.0],
"features": [
//...
]
}
A rectangle extending from 40 degrees N, 170 degrees E across the
antimeridian to 50 degrees N, 170 degrees W should be cut in two and
represented as a MultiPolygon.
{
"type": "MultiPolygon",
"coordinates": [
[
[
[180.0, 40.0], [180.0, 50.0], [170.0, 50.0],
[170.0, 40.0], [180.0, 40.0]
]
],
[
[
[-170.0, 40.0], [-170.0, 50.0], [-180.0, 50.0],
[-180.0, 40.0], [-170.0, 40.0]
]
]
]
}
5.3. The Poles
A bounding box that contains the North Pole extends from a southwest
corner of "minlat" degrees N, 180 degrees W to a northeast corner of
90 degrees N, 180 degrees E. Viewed on a globe, this bounding box
approximates a spherical cap bounded by the "minlat" circle of
latitude.
"bbox": [-180.0, minlat, 180.0, 90.0]
A bounding box that contains the South Pole extends from a southwest
corner of 90 degrees S, 180 degrees W to a northeast corner of
"maxlat" degrees S, 180 degrees E.
"bbox": [-180.0, -90.0, 180.0, maxlat]
A bounding box that just touches the North Pole and forms a slice of
an approximate spherical cap when viewed on a globe extends from a
southwest corner of "minlat" degrees N and "westlon" degrees E to a
northeast corner of 90 degrees N and "eastlon" degrees E.
"bbox": [westlon, minlat, eastlon, 90.0]
Similarly, a bounding box that just touches the South Pole and forms
a slice of an approximate spherical cap when viewed on a globe has
the following representation in GeoJSON.
"bbox": [westlon, -90.0, eastlon, maxlat]
Implementers MUST NOT use latitude values greater than 90 or less
than -90 to imply an extent that is not a spherical cap.