d3plus-shape/es/src/geom/polygonRotate.js

Fancy SVG shapes for visualizations

import pointRotate from "./pointRotate.js";

/**
    @function polygonRotate
    @desc Rotates a point around a given origin.
    @param {Array} poly The polygon to be rotated, which should be an Array of `[x, y]` values.
    @param {Number} alpha The angle in radians to rotate.
    @param {Array} [origin = [0, 0]] The origin point of the rotation, which should be an `[x, y]` formatted Array.
    @returns {Boolean}
*/
export default (function (poly, alpha) {
  var origin = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : [0, 0];
  return poly.map(function (p) {
    return pointRotate(p, alpha, origin);
  });
});