{"version":3,"file":"WebMercatorProjection-d67afe4b.js","sources":["../../../../Source/Core/WebMercatorProjection.js"],"sourcesContent":["import Cartesian3 from \"./Cartesian3.js\";\nimport Cartographic from \"./Cartographic.js\";\nimport defaultValue from \"./defaultValue.js\";\nimport defined from \"./defined.js\";\nimport DeveloperError from \"./DeveloperError.js\";\nimport Ellipsoid from \"./Ellipsoid.js\";\nimport CesiumMath from \"./Math.js\";\n\n/**\n * The map projection used by Google Maps, Bing Maps, and most of ArcGIS Online, EPSG:3857.  This\n * projection use longitude and latitude expressed with the WGS84 and transforms them to Mercator using\n * the spherical (rather than ellipsoidal) equations.\n *\n * @alias WebMercatorProjection\n * @constructor\n *\n * @param {Ellipsoid} [ellipsoid=Ellipsoid.WGS84] The ellipsoid.\n *\n * @see GeographicProjection\n */\nfunction WebMercatorProjection(ellipsoid) {\n  this._ellipsoid = defaultValue(ellipsoid, Ellipsoid.WGS84);\n  this._semimajorAxis = this._ellipsoid.maximumRadius;\n  this._oneOverSemimajorAxis = 1.0 / this._semimajorAxis;\n}\n\nObject.defineProperties(WebMercatorProjection.prototype, {\n  /**\n   * Gets the {@link Ellipsoid}.\n   *\n   * @memberof WebMercatorProjection.prototype\n   *\n   * @type {Ellipsoid}\n   * @readonly\n   */\n  ellipsoid: {\n    get: function () {\n      return this._ellipsoid;\n    },\n  },\n});\n\n/**\n * Converts a Mercator angle, in the range -PI to PI, to a geodetic latitude\n * in the range -PI/2 to PI/2.\n *\n * @param {Number} mercatorAngle The angle to convert.\n * @returns {Number} The geodetic latitude in radians.\n */\nWebMercatorProjection.mercatorAngleToGeodeticLatitude = function (\n  mercatorAngle\n) {\n  return CesiumMath.PI_OVER_TWO - 2.0 * Math.atan(Math.exp(-mercatorAngle));\n};\n\n/**\n * Converts a geodetic latitude in radians, in the range -PI/2 to PI/2, to a Mercator\n * angle in the range -PI to PI.\n *\n * @param {Number} latitude The geodetic latitude in radians.\n * @returns {Number} The Mercator angle.\n */\nWebMercatorProjection.geodeticLatitudeToMercatorAngle = function (latitude) {\n  // Clamp the latitude coordinate to the valid Mercator bounds.\n  if (latitude > WebMercatorProjection.MaximumLatitude) {\n    latitude = WebMercatorProjection.MaximumLatitude;\n  } else if (latitude < -WebMercatorProjection.MaximumLatitude) {\n    latitude = -WebMercatorProjection.MaximumLatitude;\n  }\n  const sinLatitude = Math.sin(latitude);\n  return 0.5 * Math.log((1.0 + sinLatitude) / (1.0 - sinLatitude));\n};\n\n/**\n * The maximum latitude (both North and South) supported by a Web Mercator\n * (EPSG:3857) projection.  Technically, the Mercator projection is defined\n * for any latitude up to (but not including) 90 degrees, but it makes sense\n * to cut it off sooner because it grows exponentially with increasing latitude.\n * The logic behind this particular cutoff value, which is the one used by\n * Google Maps, Bing Maps, and Esri, is that it makes the projection\n * square.  That is, the rectangle is equal in the X and Y directions.\n *\n * The constant value is computed by calling:\n *    WebMercatorProjection.mercatorAngleToGeodeticLatitude(Math.PI)\n *\n * @type {Number}\n */\nWebMercatorProjection.MaximumLatitude = WebMercatorProjection.mercatorAngleToGeodeticLatitude(\n  Math.PI\n);\n\n/**\n * Converts geodetic ellipsoid coordinates, in radians, to the equivalent Web Mercator\n * X, Y, Z coordinates expressed in meters and returned in a {@link Cartesian3}.  The height\n * is copied unmodified to the Z coordinate.\n *\n * @param {Cartographic} cartographic The cartographic coordinates in radians.\n * @param {Cartesian3} [result] The instance to which to copy the result, or undefined if a\n *        new instance should be created.\n * @returns {Cartesian3} The equivalent web mercator X, Y, Z coordinates, in meters.\n */\nWebMercatorProjection.prototype.project = function (cartographic, result) {\n  const semimajorAxis = this._semimajorAxis;\n  const x = cartographic.longitude * semimajorAxis;\n  const y =\n    WebMercatorProjection.geodeticLatitudeToMercatorAngle(\n      cartographic.latitude\n    ) * semimajorAxis;\n  const z = cartographic.height;\n\n  if (!defined(result)) {\n    return new Cartesian3(x, y, z);\n  }\n\n  result.x = x;\n  result.y = y;\n  result.z = z;\n  return result;\n};\n\n/**\n * Converts Web Mercator X, Y coordinates, expressed in meters, to a {@link Cartographic}\n * containing geodetic ellipsoid coordinates.  The Z coordinate is copied unmodified to the\n * height.\n *\n * @param {Cartesian3} cartesian The web mercator Cartesian position to unrproject with height (z) in meters.\n * @param {Cartographic} [result] The instance to which to copy the result, or undefined if a\n *        new instance should be created.\n * @returns {Cartographic} The equivalent cartographic coordinates.\n */\nWebMercatorProjection.prototype.unproject = function (cartesian, result) {\n  //>>includeStart('debug', pragmas.debug);\n  if (!defined(cartesian)) {\n    throw new DeveloperError(\"cartesian is required\");\n  }\n  //>>includeEnd('debug');\n\n  const oneOverEarthSemimajorAxis = this._oneOverSemimajorAxis;\n  const longitude = cartesian.x * oneOverEarthSemimajorAxis;\n  const latitude = WebMercatorProjection.mercatorAngleToGeodeticLatitude(\n    cartesian.y * oneOverEarthSemimajorAxis\n  );\n  const height = cartesian.z;\n\n  if (!defined(result)) {\n    return new Cartographic(longitude, latitude, height);\n  }\n\n  result.longitude = longitude;\n  result.latitude = latitude;\n  result.height = height;\n  return result;\n};\nexport default WebMercatorProjection;\n"],"names":["defaultValue","Ellipsoid","CesiumMath","defined","Cartesian3","DeveloperError","Cartographic"],"mappings":";;;;;;;;;;;;;;;;;;;;;;;;;EAQA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA,SAAS,qBAAqB,CAAC,SAAS,EAAE;EAC1C,EAAE,IAAI,CAAC,UAAU,GAAGA,iBAAY,CAAC,SAAS,EAAEC,iBAAS,CAAC,KAAK,CAAC,CAAC;EAC7D,EAAE,IAAI,CAAC,cAAc,GAAG,IAAI,CAAC,UAAU,CAAC,aAAa,CAAC;EACtD,EAAE,IAAI,CAAC,qBAAqB,GAAG,GAAG,GAAG,IAAI,CAAC,cAAc,CAAC;EACzD,CAAC;AACD;EACA,MAAM,CAAC,gBAAgB,CAAC,qBAAqB,CAAC,SAAS,EAAE;EACzD;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA,EAAE,SAAS,EAAE;EACb,IAAI,GAAG,EAAE,YAAY;EACrB,MAAM,OAAO,IAAI,CAAC,UAAU,CAAC;EAC7B,KAAK;EACL,GAAG;EACH,CAAC,CAAC,CAAC;AACH;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA,qBAAqB,CAAC,+BAA+B,GAAG;EACxD,EAAE,aAAa;EACf,EAAE;EACF,EAAE,OAAOC,4BAAU,CAAC,WAAW,GAAG,GAAG,GAAG,IAAI,CAAC,IAAI,CAAC,IAAI,CAAC,GAAG,CAAC,CAAC,aAAa,CAAC,CAAC,CAAC;EAC5E,CAAC,CAAC;AACF;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA,qBAAqB,CAAC,+BAA+B,GAAG,UAAU,QAAQ,EAAE;EAC5E;EACA,EAAE,IAAI,QAAQ,GAAG,qBAAqB,CAAC,eAAe,EAAE;EACxD,IAAI,QAAQ,GAAG,qBAAqB,CAAC,eAAe,CAAC;EACrD,GAAG,MAAM,IAAI,QAAQ,GAAG,CAAC,qBAAqB,CAAC,eAAe,EAAE;EAChE,IAAI,QAAQ,GAAG,CAAC,qBAAqB,CAAC,eAAe,CAAC;EACtD,GAAG;EACH,EAAE,MAAM,WAAW,GAAG,IAAI,CAAC,GAAG,CAAC,QAAQ,CAAC,CAAC;EACzC,EAAE,OAAO,GAAG,GAAG,IAAI,CAAC,GAAG,CAAC,CAAC,GAAG,GAAG,WAAW,KAAK,GAAG,GAAG,WAAW,CAAC,CAAC,CAAC;EACnE,CAAC,CAAC;AACF;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA,qBAAqB,CAAC,eAAe,GAAG,qBAAqB,CAAC,+BAA+B;EAC7F,EAAE,IAAI,CAAC,EAAE;EACT,CAAC,CAAC;AACF;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA,qBAAqB,CAAC,SAAS,CAAC,OAAO,GAAG,UAAU,YAAY,EAAE,MAAM,EAAE;EAC1E,EAAE,MAAM,aAAa,GAAG,IAAI,CAAC,cAAc,CAAC;EAC5C,EAAE,MAAM,CAAC,GAAG,YAAY,CAAC,SAAS,GAAG,aAAa,CAAC;EACnD,EAAE,MAAM,CAAC;EACT,IAAI,qBAAqB,CAAC,+BAA+B;EACzD,MAAM,YAAY,CAAC,QAAQ;EAC3B,KAAK,GAAG,aAAa,CAAC;EACtB,EAAE,MAAM,CAAC,GAAG,YAAY,CAAC,MAAM,CAAC;AAChC;EACA,EAAE,IAAI,CAACC,YAAO,CAAC,MAAM,CAAC,EAAE;EACxB,IAAI,OAAO,IAAIC,kBAAU,CAAC,CAAC,EAAE,CAAC,EAAE,CAAC,CAAC,CAAC;EACnC,GAAG;AACH;EACA,EAAE,MAAM,CAAC,CAAC,GAAG,CAAC,CAAC;EACf,EAAE,MAAM,CAAC,CAAC,GAAG,CAAC,CAAC;EACf,EAAE,MAAM,CAAC,CAAC,GAAG,CAAC,CAAC;EACf,EAAE,OAAO,MAAM,CAAC;EAChB,CAAC,CAAC;AACF;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA;EACA,qBAAqB,CAAC,SAAS,CAAC,SAAS,GAAG,UAAU,SAAS,EAAE,MAAM,EAAE;EACzE;EACA,EAAE,IAAI,CAACD,YAAO,CAAC,SAAS,CAAC,EAAE;EAC3B,IAAI,MAAM,IAAIE,2BAAc,CAAC,uBAAuB,CAAC,CAAC;EACtD,GAAG;EACH;AACA;EACA,EAAE,MAAM,yBAAyB,GAAG,IAAI,CAAC,qBAAqB,CAAC;EAC/D,EAAE,MAAM,SAAS,GAAG,SAAS,CAAC,CAAC,GAAG,yBAAyB,CAAC;EAC5D,EAAE,MAAM,QAAQ,GAAG,qBAAqB,CAAC,+BAA+B;EACxE,IAAI,SAAS,CAAC,CAAC,GAAG,yBAAyB;EAC3C,GAAG,CAAC;EACJ,EAAE,MAAM,MAAM,GAAG,SAAS,CAAC,CAAC,CAAC;AAC7B;EACA,EAAE,IAAI,CAACF,YAAO,CAAC,MAAM,CAAC,EAAE;EACxB,IAAI,OAAO,IAAIG,oBAAY,CAAC,SAAS,EAAE,QAAQ,EAAE,MAAM,CAAC,CAAC;EACzD,GAAG;AACH;EACA,EAAE,MAAM,CAAC,SAAS,GAAG,SAAS,CAAC;EAC/B,EAAE,MAAM,CAAC,QAAQ,GAAG,QAAQ,CAAC;EAC7B,EAAE,MAAM,CAAC,MAAM,GAAG,MAAM,CAAC;EACzB,EAAE,OAAO,MAAM,CAAC;EAChB,CAAC;;;;;;;;"}