Merge vector-2.4 branch back to trunk.

svn merge sandbox/vector-2.4/@2307 sandbox/vector-2.4/@HEAD trunk/openlayers/ git-svn-id: http://svn.openlayers.org/trunk/openlayers@2803 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf
2007-03-16 13:23:56 +00:00
parent 8b9d974dc2
commit 3ca974acec
159 changed files with 10193 additions and 343 deletions
@@ -0,0 +1,113 @@
+/* Copyright (c) 2006 MetaCarta, Inc., published under a modified BSD license.
+ * See http://svn.openlayers.org/trunk/openlayers/repository-license.txt 
+ * for the full text of the license. */
+
+/**
+ * @class
+ * 
+ * A Linear Ring is a special LineString which is closed. It closes itself 
+ * automatically on every addPoint/removePoint by adding a copy of the first
+ * point as the last point. 
+ * 
+ * Also, as it is the first in the line family to close itself, a getArea()
+ * function is defined to calculate the enclosed area of the linearRing
+ * 
+ * @requires OpenLayers/Geometry/LineString.js
+ */
+OpenLayers.Geometry.LinearRing = OpenLayers.Class.create();
+OpenLayers.Geometry.LinearRing.prototype = 
+    OpenLayers.Class.inherit(OpenLayers.Geometry.LineString, {
+
+    /**
+     * @constructor
+     *
+     * @param {Array(OpenLayers.Geometry.Point)} points
+     */
+    initialize: function(points) {
+        OpenLayers.Geometry.LineString.prototype.initialize.apply(this, 
+                                                                  arguments);
+    },
+    
+    /**
+     * @returns An exact clone of this OpenLayers.Geometry.LinearRing
+     * @type OpenLayers.Geometry.LinearRing
+     */
+    clone: function (obj) {
+        if (obj == null) {
+            obj = new OpenLayers.Geometry.LinearRing();
+        }
+        
+        for (var i = 0; i < this.components.length; i++) {
+            obj.addComponent(this.components[i].clone());
+        }
+        
+        return obj;
+    },
+    
+    /**
+     * Adds a point to geometry components
+     *
+     * @param {OpenLayers.Geometry.Point} point
+     * @param {int} index Index into the array to insert the component
+     */ 
+    addComponent: function(point, index) {
+        //remove last point
+        var lastPoint = this.components[this.components.length-1];
+        OpenLayers.Geometry.Curve.prototype.removeComponent.apply(this, 
+                                                                  [lastPoint]);
+ 
+        //add our point
+        OpenLayers.Geometry.LineString.prototype.addComponent.apply(this, 
+                                                                    arguments);
+        //append copy of first point
+        var firstPoint = this.components[0];
+        OpenLayers.Geometry.Curve.prototype.addComponent.apply(this, 
+                                                         [firstPoint.clone()]);
+    },
+    
+    /**
+     * Removes a point from geometry components
+     *
+     * @param {OpenLayers.Geometry.Point} point
+     */
+    removeComponent: function(point) {
+        if (this.components.length > 4) {
+
+            //remove last point
+            var lastPoint = this.components[this.components.length-1];
+            OpenLayers.Geometry.Curve.prototype.removeComponent.apply(this, 
+                                                                 [lastPoint]);
+            
+            //remove our point
+            OpenLayers.Geometry.LineString.prototype.removeComponent.apply(this, 
+                                                                    arguments);
+            //append copy of first point
+            var firstPoint = this.components[0];
+            OpenLayers.Geometry.Curve.prototype.addComponent.apply(this, 
+                                                         [firstPoint.clone()]);
+        }
+    },
+    
+    /** Note: The area is positive if the ring is oriented CW, otherwise
+     *         it will be negative.
+     * 
+     * @returns The signed area for a ring.
+     * @type float
+     */
+    getArea: function() {
+        var area = 0.0;
+        if ( this.components && (this.components.length > 2)) {
+            var sum = 0.0;
+            for (var i = 0; i < this.components.length - 1; i++) {
+                var b = this.components[i];
+                var c = this.components[i+1];
+                sum += (b.x + c.x) * (c.y - b.y);
+            }
+            area = - sum / 2.0;
+        }
+        return area;
+    },
+
+    /** @final @type String */
+    CLASS_NAME: "OpenLayers.Geometry.LinearRing"
+});