Equal-Area Hex Grids on the 'Snyder' 'ISEA' 'Icosahedron'
Convert hexify grid to 'dggridR'-compatible grid object
Convert HexData to sf Object
Convert HexData to tibble
Calculate resolution for target area
Convert cell ID to hierarchical index string
Convert cell ID to longitude/latitude
Convert cell IDs to sf polygons
Get Cell IDs
Find closest resolution for target cell area
Get grid statistics for Earth coverage
Create DGGRID 43H aperture sequence
Validate 'dggridR' grid compatibility with hexify
Verify grid object
Extract grid from various objects
Convert 'dggridR' grid object to hexify_grid
Get children cells
Get parent cell
Globe center presets
Clip hexagon grid to polygon boundary
Generate a global hexagon grid
Get Grid Specification
Generate a rectangular grid of hexagons
Build an sf POLYGON from six (lon, lat) corner pairs
Create a Hexagonal Grid Specification
HexData Class
HexData S4 Methods
Convert HexGridInfo to legacy hexify_grid
HexGridInfo Class
HexGridInfo S4 Methods
Convert area to effective resolution
Assign hex cells ('ISEA3H', aperture 3) for lon/lat
Initialize icosahedron geometry
Get cell info from cell ID
Convert Cell ID to Icosa Triangle coordinates
Convert cell coordinates to index string
Convert cell ID to longitude/latitude
Convert Cell ID to PLANE coordinates
Convert Cell ID to Quad IJ coordinates
Convert Cell ID to Quad XY coordinates
Convert cell IDs to sf polygons
Compare two indices
Compare grid resolutions
Get default index type for aperture
Convert effective resolution to area
Convert effective resolution to index resolution
Get icosahedron face centers
Forward projection to specific face
Forward Snyder projection
Get children indices
Get parent index
Get current precision settings
Get index resolution
Convert cell ID to longitude/latitude using a grid object
Generate a global grid of hexagon polygons
Generate a rectangular grid of hexagon polygons
Convert longitude/latitude to cell ID using a grid object
Convert legacy hexify_grid to HexGridInfo
Create a hexagonal grid specification
Convert hierarchical index strings to longitude/latitude centers
Create a ggplot2 visualization of hexagonal grid cells
Convert Icosa Triangle coordinates to PLANE coordinates
Convert Icosa Triangle to Quad IJ coordinates
Convert Icosa Triangle to Quad XY coordinates
Convert index string to cell coordinates
Convert index string to longitude/latitude
Inverse Snyder projection
Check if index type is valid for aperture
Convert longitude/latitude to cell ID
Convert longitude/latitude to hexagonal cell hierarchical index
Convert longitude/latitude to index string
Convert longitude/latitude to PLANE coordinates
Convert longitude/latitude to Quad IJ coordinates
Get inverse projection statistics
Convert Quad IJ coordinates to cell ID
Convert Quad IJ to Icosa Triangle coordinates
Convert Quad IJ to Quad XY (continuous coordinates)
Convert Quad XY coordinates to Cell ID
Convert Quad XY to Icosa Triangle coordinates
Convert index resolution to effective resolution
Round-trip accuracy test
Set inverse projection precision
Set verbose mode for inverse projection
Determine which face contains a point
Get canonical form of Z7 index
Coordinate Conversions
Core Grid Construction
hexify
Grid Statistics
Assign hexagonal DGGS cell IDs to geographic points
Decode a cell index to face, i, j, and resolution
Check if object is HexData
Check if object is HexGridInfo
Convert longitude/latitude to cell ID
Get Number of Cells
Create a HexData Object (Internal)
Plot hexagonized globe
Plot hexagonal grid clipped to a polygon boundary
Quick world map plot
Plot HexData objects
Provides functions to build and use equal-area hexagonal discrete global grids using the 'Snyder' 'ISEA' projection ('Snyder' 1992 <doi:10.3138/27H7-8K88-4882-1752>). Implements the 'ISEA' discrete global grid system ('Sahr', 'White' and 'Kimerling' 2003 <doi:10.1559/152304003100011090>). Includes a fast 'C++' core for projection and aperture quantization, and 'sf'/'terra'-compatible R wrappers for grid generation and coordinate assignment. Output is compatible with 'dggridR' for interoperability.