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Build tools and sources for developing OpenLayers based mapping applications

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goog.provide('ol.format.Polyline'); goog.require('ol'); goog.require('ol.asserts'); goog.require('ol.Feature'); goog.require('ol.format.Feature'); goog.require('ol.format.TextFeature'); goog.require('ol.geom.GeometryLayout'); goog.require('ol.geom.LineString'); goog.require('ol.geom.SimpleGeometry'); goog.require('ol.geom.flat.flip'); goog.require('ol.geom.flat.inflate'); goog.require('ol.proj'); /** * @classdesc * Feature format for reading and writing data in the Encoded * Polyline Algorithm Format. * * @constructor * @extends {ol.format.TextFeature} * @param {olx.format.PolylineOptions=} opt_options * Optional configuration object. * @api stable */ ol.format.Polyline = function(opt_options) { var options = opt_options ? opt_options : {}; ol.format.TextFeature.call(this); /** * @inheritDoc */ this.defaultDataProjection = ol.proj.get('EPSG:4326'); /** * @private * @type {number} */ this.factor_ = options.factor ? options.factor : 1e5; /** * @private * @type {ol.geom.GeometryLayout} */ this.geometryLayout_ = options.geometryLayout ? options.geometryLayout : ol.geom.GeometryLayout.XY; }; ol.inherits(ol.format.Polyline, ol.format.TextFeature); /** * Encode a list of n-dimensional points and return an encoded string * * Attention: This function will modify the passed array! * * @param {Array.<number>} numbers A list of n-dimensional points. * @param {number} stride The number of dimension of the points in the list. * @param {number=} opt_factor The factor by which the numbers will be * multiplied. The remaining decimal places will get rounded away. * Default is `1e5`. * @return {string} The encoded string. * @api */ ol.format.Polyline.encodeDeltas = function(numbers, stride, opt_factor) { var factor = opt_factor ? opt_factor : 1e5; var d; var lastNumbers = new Array(stride); for (d = 0; d < stride; ++d) { lastNumbers[d] = 0; } var i, ii; for (i = 0, ii = numbers.length; i < ii;) { for (d = 0; d < stride; ++d, ++i) { var num = numbers[i]; var delta = num - lastNumbers[d]; lastNumbers[d] = num; numbers[i] = delta; } } return ol.format.Polyline.encodeFloats(numbers, factor); }; /** * Decode a list of n-dimensional points from an encoded string * * @param {string} encoded An encoded string. * @param {number} stride The number of dimension of the points in the * encoded string. * @param {number=} opt_factor The factor by which the resulting numbers will * be divided. Default is `1e5`. * @return {Array.<number>} A list of n-dimensional points. * @api */ ol.format.Polyline.decodeDeltas = function(encoded, stride, opt_factor) { var factor = opt_factor ? opt_factor : 1e5; var d; /** @type {Array.<number>} */ var lastNumbers = new Array(stride); for (d = 0; d < stride; ++d) { lastNumbers[d] = 0; } var numbers = ol.format.Polyline.decodeFloats(encoded, factor); var i, ii; for (i = 0, ii = numbers.length; i < ii;) { for (d = 0; d < stride; ++d, ++i) { lastNumbers[d] += numbers[i]; numbers[i] = lastNumbers[d]; } } return numbers; }; /** * Encode a list of floating point numbers and return an encoded string * * Attention: This function will modify the passed array! * * @param {Array.<number>} numbers A list of floating point numbers. * @param {number=} opt_factor The factor by which the numbers will be * multiplied. The remaining decimal places will get rounded away. * Default is `1e5`. * @return {string} The encoded string. * @api */ ol.format.Polyline.encodeFloats = function(numbers, opt_factor) { var factor = opt_factor ? opt_factor : 1e5; var i, ii; for (i = 0, ii = numbers.length; i < ii; ++i) { numbers[i] = Math.round(numbers[i] * factor); } return ol.format.Polyline.encodeSignedIntegers(numbers); }; /** * Decode a list of floating point numbers from an encoded string * * @param {string} encoded An encoded string. * @param {number=} opt_factor The factor by which the result will be divided. * Default is `1e5`. * @return {Array.<number>} A list of floating point numbers. * @api */ ol.format.Polyline.decodeFloats = function(encoded, opt_factor) { var factor = opt_factor ? opt_factor : 1e5; var numbers = ol.format.Polyline.decodeSignedIntegers(encoded); var i, ii; for (i = 0, ii = numbers.length; i < ii; ++i) { numbers[i] /= factor; } return numbers; }; /** * Encode a list of signed integers and return an encoded string * * Attention: This function will modify the passed array! * * @param {Array.<number>} numbers A list of signed integers. * @return {string} The encoded string. */ ol.format.Polyline.encodeSignedIntegers = function(numbers) { var i, ii; for (i = 0, ii = numbers.length; i < ii; ++i) { var num = numbers[i]; numbers[i] = (num < 0) ? ~(num << 1) : (num << 1); } return ol.format.Polyline.encodeUnsignedIntegers(numbers); }; /** * Decode a list of signed integers from an encoded string * * @param {string} encoded An encoded string. * @return {Array.<number>} A list of signed integers. */ ol.format.Polyline.decodeSignedIntegers = function(encoded) { var numbers = ol.format.Polyline.decodeUnsignedIntegers(encoded); var i, ii; for (i = 0, ii = numbers.length; i < ii; ++i) { var num = numbers[i]; numbers[i] = (num & 1) ? ~(num >> 1) : (num >> 1); } return numbers; }; /** * Encode a list of unsigned integers and return an encoded string * * @param {Array.<number>} numbers A list of unsigned integers. * @return {string} The encoded string. */ ol.format.Polyline.encodeUnsignedIntegers = function(numbers) { var encoded = ''; var i, ii; for (i = 0, ii = numbers.length; i < ii; ++i) { encoded += ol.format.Polyline.encodeUnsignedInteger(numbers[i]); } return encoded; }; /** * Decode a list of unsigned integers from an encoded string * * @param {string} encoded An encoded string. * @return {Array.<number>} A list of unsigned integers. */ ol.format.Polyline.decodeUnsignedIntegers = function(encoded) { var numbers = []; var current = 0; var shift = 0; var i, ii; for (i = 0, ii = encoded.length; i < ii; ++i) { var b = encoded.charCodeAt(i) - 63; current |= (b & 0x1f) << shift; if (b < 0x20) { numbers.push(current); current = 0; shift = 0; } else { shift += 5; } } return numbers; }; /** * Encode one single unsigned integer and return an encoded string * * @param {number} num Unsigned integer that should be encoded. * @return {string} The encoded string. */ ol.format.Polyline.encodeUnsignedInteger = function(num) { var value, encoded = ''; while (num >= 0x20) { value = (0x20 | (num & 0x1f)) + 63; encoded += String.fromCharCode(value); num >>= 5; } value = num + 63; encoded += String.fromCharCode(value); return encoded; }; /** * Read the feature from the Polyline source. The coordinates are assumed to be * in two dimensions and in latitude, longitude order. * * @function * @param {Document|Node|Object|string} source Source. * @param {olx.format.ReadOptions=} opt_options Read options. * @return {ol.Feature} Feature. * @api stable */ ol.format.Polyline.prototype.readFeature; /** * @inheritDoc */ ol.format.Polyline.prototype.readFeatureFromText = function(text, opt_options) { var geometry = this.readGeometryFromText(text, opt_options); return new ol.Feature(geometry); }; /** * Read the feature from the source. As Polyline sources contain a single * feature, this will return the feature in an array. * * @function * @param {Document|Node|Object|string} source Source. * @param {olx.format.ReadOptions=} opt_options Read options. * @return {Array.<ol.Feature>} Features. * @api stable */ ol.format.Polyline.prototype.readFeatures; /** * @inheritDoc */ ol.format.Polyline.prototype.readFeaturesFromText = function(text, opt_options) { var feature = this.readFeatureFromText(text, opt_options); return [feature]; }; /** * Read the geometry from the source. * * @function * @param {Document|Node|Object|string} source Source. * @param {olx.format.ReadOptions=} opt_options Read options. * @return {ol.geom.Geometry} Geometry. * @api stable */ ol.format.Polyline.prototype.readGeometry; /** * @inheritDoc */ ol.format.Polyline.prototype.readGeometryFromText = function(text, opt_options) { var stride = ol.geom.SimpleGeometry.getStrideForLayout(this.geometryLayout_); var flatCoordinates = ol.format.Polyline.decodeDeltas( text, stride, this.factor_); ol.geom.flat.flip.flipXY( flatCoordinates, 0, flatCoordinates.length, stride, flatCoordinates); var coordinates = ol.geom.flat.inflate.coordinates( flatCoordinates, 0, flatCoordinates.length, stride); return /** @type {ol.geom.Geometry} */ ( ol.format.Feature.transformWithOptions( new ol.geom.LineString(coordinates, this.geometryLayout_), false, this.adaptOptions(opt_options))); }; /** * Read the projection from a Polyline source. * * @function * @param {Document|Node|Object|string} source Source. * @return {ol.proj.Projection} Projection. * @api stable */ ol.format.Polyline.prototype.readProjection; /** * @inheritDoc */ ol.format.Polyline.prototype.writeFeatureText = function(feature, opt_options) { var geometry = feature.getGeometry(); if (geometry) { return this.writeGeometryText(geometry, opt_options); } else { ol.asserts.assert(false, 40); // Expected `feature` to have a geometry return ''; } }; /** * @inheritDoc */ ol.format.Polyline.prototype.writeFeaturesText = function(features, opt_options) { ol.DEBUG && console.assert(features.length == 1, 'features array should have 1 item'); return this.writeFeatureText(features[0], opt_options); }; /** * Write a single geometry in Polyline format. * * @function * @param {ol.geom.Geometry} geometry Geometry. * @param {olx.format.WriteOptions=} opt_options Write options. * @return {string} Geometry. * @api stable */ ol.format.Polyline.prototype.writeGeometry; /** * @inheritDoc */ ol.format.Polyline.prototype.writeGeometryText = function(geometry, opt_options) { geometry = /** @type {ol.geom.LineString} */ (ol.format.Feature.transformWithOptions( geometry, true, this.adaptOptions(opt_options))); var flatCoordinates = geometry.getFlatCoordinates(); var stride = geometry.getStride(); ol.geom.flat.flip.flipXY( flatCoordinates, 0, flatCoordinates.length, stride, flatCoordinates); return ol.format.Polyline.encodeDeltas(flatCoordinates, stride, this.factor_); };