Create Grid

Draft: written, not yet checked by a person Operation · create-grid

A layer of square or hexagonal cells of a given size covering another layer's extent.

Pitfall. Engines align the grid differently (to the extent's corner, or to multiples of the cell size), so cells and counts can differ.

About this operation
Also called	Create Fishnet, Generate Tessellation, vector grid, hexagon grid, square grid
Group	`vector/geometry`
Checks	`crs.measure`
Pitfalls	1 listed above
Columbus tool	Not stated
Notes	Not stated
Status	active
Broader	Not stated
Narrower	Not stated
Related	`voronoi`

Parameters

Name	Type	Required	Default	Values	Note
`cell_size`	length	yes	Not stated	Not stated	Cell width, in the CRS's units (for hexagons, engines differ on which dimension).
`shape`	enum	no	`square`	`square, hexagon`	Not stated

Inputs and outputs

Direction	Name	Type	Geometry	Note
Input	`layer`	vector	Not stated	The grid covers this layer's extent.
Output	`output`	vector	polygon	Not stated

In each engine

Engine	Tool	Parameters	Differences
`geopandas`	`geopandas.make_grid`	`cell_size` → `cell_size` `shape` → `grid_type` `layer` → `input_geometry`	Keeps only cells that intersect the geometry (intersect = True).
`geopandas`	`geopandas.GeoSeries.make_grid`	`cell_size` → `cell_size` `shape` → `grid_type`	Called on a GeoSeries; keeps only cells that intersect it.
`grass`	`v.mkgrid`	`cell_size` → `box` : width and height: box=10,10. `shape` → `flag_h` : square = no; hexagon = yes `layer` The grid covers the computational region (position = region). `output` → `map`	None noted
`postgis`	`st_hexagongrid`	`cell_size` → `size` `shape` always hexagon. ST_SquareGrid for squares. `layer` → `bounds`	size is the hexagon's edge length; the grid is aligned to the origin.
`postgis`	`st_squaregrid`	`cell_size` → `size` `shape` always square. ST_HexagonGrid for hexagons. `layer` → `bounds`	The grid is aligned to multiples of the cell size from the origin, not to the bounds' corner; returns (geom, i, j) rows for every cell that intersects the bounds, including cells that only touch their edge (121 cells of 10 m for a 100 m square at the origin, in the equivalence tests).
`qgis`	`native:creategrid`	`cell_size` HSPACING and VSPACING: the cell width and height. `shape` → `TYPE` : square = 2; hexagon = 4 `layer` → `EXTENT` `output` → `OUTPUT`	None noted
`sf`	`sf::st_make_grid`	`cell_size` → `cellsize` `shape` → `square` : square = yes; hexagon = no `layer` → `x`	The grid starts at the layer's bounding box corner (offset); n gives the number of cells instead of their size.
`turf-js`	`turf.squareGrid`	`cell_size` → `cellSide` : In options.units (default kilometers). `shape` always square. turf.hexGrid for hexagons. `layer` bbox: [west, south, east, north] in longitude/latitude.	Turf works on GeoJSON in longitude/latitude (WGS 84); data in another CRS must be reprojected first.
`whiteboxtools`	`CreateRectangularVectorGrid`	`cell_size` width and height: the cell's width and height. `shape` always square. CreateHexagonalVectorGrid for hexagons. `layer` → `input` `output` → `output`	xorig and yorig set where the grid starts (default 0, 0).