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+/* Copyright (c) 2006-2013 by OpenLayers Contributors (see authors.txt for
+ * full list of contributors). Published under the 2-clause BSD license.
+ * See license.txt in the OpenLayers distribution or repository for the
+ * full text of the license. */
+
+/**
+ * @requires OpenLayers/Geometry/MultiPoint.js
+ */
+
+/**
+ * Class: OpenLayers.Geometry.Curve
+ * A Curve is a MultiPoint, whose points are assumed to be connected. To
+ * this end, we provide a "getLength()" function, which iterates through
+ * the points, summing the distances between them.
+ *
+ * Inherits:
+ * - <OpenLayers.Geometry.MultiPoint>
+ */
+OpenLayers.Geometry.Curve = OpenLayers.Class(OpenLayers.Geometry.MultiPoint, {
+
+ /**
+ * Property: componentTypes
+ * {Array(String)} An array of class names representing the types of
+ * components that the collection can include. A null
+ * value means the component types are not restricted.
+ */
+ componentTypes: ["OpenLayers.Geometry.Point"],
+
+ /**
+ * Constructor: OpenLayers.Geometry.Curve
+ *
+ * Parameters:
+ * point - {Array(<OpenLayers.Geometry.Point>)}
+ */
+
+ /**
+ * APIMethod: getLength
+ *
+ * Returns:
+ * {Float} The length of the curve
+ */
+ getLength: function() {
+ var length = 0.0;
+ if ( this.components && (this.components.length > 1)) {
+ for(var i=1, len=this.components.length; i<len; i++) {
+ length += this.components[i-1].distanceTo(this.components[i]);
+ }
+ }
+ return length;
+ },
+
+ /**
+ * APIMethod: getGeodesicLength
+ * Calculate the approximate length of the geometry were it projected onto
+ * the earth.
+ *
+ * projection - {<OpenLayers.Projection>} The spatial reference system
+ * for the geometry coordinates. If not provided, Geographic/WGS84 is
+ * assumed.
+ *
+ * Returns:
+ * {Float} The appoximate geodesic length of the geometry in meters.
+ */
+ getGeodesicLength: function(projection) {
+ var geom = this; // so we can work with a clone if needed
+ if(projection) {
+ var gg = new OpenLayers.Projection("EPSG:4326");
+ if(!gg.equals(projection)) {
+ geom = this.clone().transform(projection, gg);
+ }
+ }
+ var length = 0.0;
+ if(geom.components && (geom.components.length > 1)) {
+ var p1, p2;
+ for(var i=1, len=geom.components.length; i<len; i++) {
+ p1 = geom.components[i-1];
+ p2 = geom.components[i];
+ // this returns km and requires lon/lat properties
+ length += OpenLayers.Util.distVincenty(
+ {lon: p1.x, lat: p1.y}, {lon: p2.x, lat: p2.y}
+ );
+ }
+ }
+ // convert to m
+ return length * 1000;
+ },
+
+ CLASS_NAME: "OpenLayers.Geometry.Curve"
+});