@visx/vendor/vendor-cjs/d3-geo/src/length.js

vendored packages for visx

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = _default;
var _index = require("../../../vendor-cjs/d3-array/src/index.js");
var _math = require("./math.js");
var _noop = _interopRequireDefault(require("./noop.js"));
var _stream = _interopRequireDefault(require("./stream.js"));
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
var lengthSum, lambda0, sinPhi0, cosPhi0;
var lengthStream = {
  sphere: _noop.default,
  point: _noop.default,
  lineStart: lengthLineStart,
  lineEnd: _noop.default,
  polygonStart: _noop.default,
  polygonEnd: _noop.default
};
function lengthLineStart() {
  lengthStream.point = lengthPointFirst;
  lengthStream.lineEnd = lengthLineEnd;
}
function lengthLineEnd() {
  lengthStream.point = lengthStream.lineEnd = _noop.default;
}
function lengthPointFirst(lambda, phi) {
  lambda *= _math.radians, phi *= _math.radians;
  lambda0 = lambda, sinPhi0 = (0, _math.sin)(phi), cosPhi0 = (0, _math.cos)(phi);
  lengthStream.point = lengthPoint;
}
function lengthPoint(lambda, phi) {
  lambda *= _math.radians, phi *= _math.radians;
  var sinPhi = (0, _math.sin)(phi),
    cosPhi = (0, _math.cos)(phi),
    delta = (0, _math.abs)(lambda - lambda0),
    cosDelta = (0, _math.cos)(delta),
    sinDelta = (0, _math.sin)(delta),
    x = cosPhi * sinDelta,
    y = cosPhi0 * sinPhi - sinPhi0 * cosPhi * cosDelta,
    z = sinPhi0 * sinPhi + cosPhi0 * cosPhi * cosDelta;
  lengthSum.add((0, _math.atan2)((0, _math.sqrt)(x * x + y * y), z));
  lambda0 = lambda, sinPhi0 = sinPhi, cosPhi0 = cosPhi;
}
function _default(object) {
  lengthSum = new _index.Adder();
  (0, _stream.default)(object, lengthStream);
  return +lengthSum;
}