index.cjs 1.3 KB

1234567891011121314151617181920212223242526272829303132333435
  1. "use strict";Object.defineProperty(exports, "__esModule", {value: true});// index.ts
  2. var _helpers = require('@turf/helpers');
  3. var _invariant = require('@turf/invariant');
  4. function rhumbBearing(start, end, options = {}) {
  5. let bear360;
  6. if (options.final) {
  7. bear360 = calculateRhumbBearing(_invariant.getCoord.call(void 0, end), _invariant.getCoord.call(void 0, start));
  8. } else {
  9. bear360 = calculateRhumbBearing(_invariant.getCoord.call(void 0, start), _invariant.getCoord.call(void 0, end));
  10. }
  11. const bear180 = bear360 > 180 ? -(360 - bear360) : bear360;
  12. return bear180;
  13. }
  14. function calculateRhumbBearing(from, to) {
  15. const phi1 = _helpers.degreesToRadians.call(void 0, from[1]);
  16. const phi2 = _helpers.degreesToRadians.call(void 0, to[1]);
  17. let deltaLambda = _helpers.degreesToRadians.call(void 0, to[0] - from[0]);
  18. if (deltaLambda > Math.PI) {
  19. deltaLambda -= 2 * Math.PI;
  20. }
  21. if (deltaLambda < -Math.PI) {
  22. deltaLambda += 2 * Math.PI;
  23. }
  24. const deltaPsi = Math.log(
  25. Math.tan(phi2 / 2 + Math.PI / 4) / Math.tan(phi1 / 2 + Math.PI / 4)
  26. );
  27. const theta = Math.atan2(deltaLambda, deltaPsi);
  28. return (_helpers.radiansToDegrees.call(void 0, theta) + 360) % 360;
  29. }
  30. var turf_rhumb_bearing_default = rhumbBearing;
  31. exports.default = turf_rhumb_bearing_default; exports.rhumbBearing = rhumbBearing;
  32. //# sourceMappingURL=index.cjs.map