generates a flat array of data for a four quadrant grid

getGrid.js

export function getGrid (size) {
  const length = Math.pow(size, 2)
  const offset = (size / 2) * -1

  const grid = Array.from({ length }).map((_, index, array) => {
    const row = Math.floor(index / size)
    const column = index % size

    const x = row + offset + 0.5
    const y = column + offset + 0.5
    const i = index + 1
    const r = array.length - index

    return { x, y, i, r, row, column }
  })

  return grid
}