xy_to_gridcells: Convert between Web Mercator Coordinates and Grid Cell...

In falling-fruit/fruitr: R functions for Falling Fruit

Convert between Web Mercator Coordinates and Grid Cell Indices

Description

Converts between projected Web Mercator (EPSG:3857) coordinates in meters and quadtree grid cell indices. The conversion back from grid cell indices returns the coordinates of the lower left corner of the cell.

Usage

xy_to_gridcells(xy, zoom = 0L)

gridcells_to_xy(xyz)

Arguments

xy	Rows of Web Mercator coordinates in meters (x, y).
zoom	Zoom level(s) of the quadtree dividing the Earth into a square 2^{zoom} grid.
xyz	Rows of zero-based, integer grid cell indices (x, y, zoom).

Examples

xy <- cbind(x = 0, y = 0)
xyz <- xy_to_gridcells(xy, zoom = 1)
gridcells_to_xy(xyz)
xyz <- xy_to_gridcells(xy, zoom = 0)
gridcells_to_xy(xyz)

falling-fruit/fruitr documentation built on Dec. 21, 2024, 8:32 p.m.