@thi.ng/grid-iterators/interleave.js

2D grid and shape iterators w/ multiple orderings

import { map } from "@thi.ng/transducers/map";
import { range2d } from "@thi.ng/transducers/range2d";
import { __opts } from "./utils.js";
const interleaveColumns2d = (opts) => __interleave(opts, [0, 1], [1, 0]);
const interleaveRows2d = (opts) => __interleave(opts, [1, 0], [0, 1]);
function* __interleave(opts, order, [x, y]) {
  const { cols, rows, tx } = __opts(opts);
  const step = (opts.step ?? 2) | 0;
  const [outer, inner] = order.map((x2) => [cols, rows][x2]);
  for (let j = 0; j < step; j++) {
    yield* map((p) => tx(p[x], p[y]), range2d(0, inner, j, outer, 1, step));
  }
}
export {
  __interleave,
  interleaveColumns2d,
  interleaveRows2d
};