@thi.ng/geom-axidraw/sort.js

Conversion and preparation of thi.ng/geom shapes & shape groups to/from AxiDraw pen plotter draw commands

import { sortByCachedKey } from "@thi.ng/arrays/sort-cached";
import { compareNumAsc } from "@thi.ng/compare/numeric";
import { KdTreeSet } from "@thi.ng/geom-accel/kd-tree-set";
import { centroid } from "@thi.ng/geom/centroid";
import { ZERO2 } from "@thi.ng/vectors/api";
import { distSq2 } from "@thi.ng/vectors/distsq";
const pointsByNearestNeighbor = (accel = new KdTreeSet(2), ref = ZERO2) => function* (pts) {
  accel.into(pts);
  while (accel.size) {
    ref = accel.queryKeys(ref, 1e4, 1)[0];
    accel.remove(ref);
    yield ref;
  }
};
const pointsByProximity = (ref = ZERO2) => (pts) => {
  return sortByCachedKey(
    pts.slice(),
    (p) => distSq2(p, ref),
    compareNumAsc
  );
};
const shapesByProximity = (ref = ZERO2) => (shapes) => {
  return sortByCachedKey(
    shapes.slice(),
    (s) => distSq2(centroid(s) || ZERO2, ref),
    compareNumAsc
  );
};
const shapesByNearestNeighbor = (accel, ref = ZERO2) => function* (shapes) {
  accel.into(
    shapes.map(
      (s) => [centroid(s) || [0, 0], s]
    )
  );
  while (accel.size) {
    const pair = accel.query(ref, 1e4, 1)[0];
    ref = pair[0];
    accel.remove(ref);
    yield pair[1];
  }
};
export {
  pointsByNearestNeighbor,
  pointsByProximity,
  shapesByNearestNeighbor,
  shapesByProximity
};