Module projection 

Web Mercator projection — port of projection.ts.

Converts between geographic coordinates (longitude/latitude in degrees) and world/pixel coordinates used by slippy-map tile systems.

Constants

EARTH_RADIUS

Earth radius used by Web Mercator in meters.

MAX_LAT

Maximum latitude representable in Web Mercator (≈85.05112878°).

TILE_SIZE

Tile size in pixels.

Functions

clamp_lat

Clamp latitude to the Web Mercator valid range.

from_pixels

Convert pixel coordinates at a zoom level back to lon/lat.

meters_per_pixel

Meters per pixel at a given latitude and zoom.

project

Project longitude/latitude (degrees) to normalized world coordinates in [0, 1).

to_pixels

Project lon/lat to pixel coordinates at a given zoom level.

unproject

Inverse-project normalized world coordinates in [0, 1) back to lon/lat degrees.