Include tests/test_Projection.html and lib/OpenLayers/Projection.js (taken from

projections.2.patch). (Closes #1035) git-svn-id: http://svn.openlayers.org/trunk/openlayers@5405 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf
2007-12-14 08:36:36 +00:00
parent 47edbf4524
commit 22bbf98398
2 changed files with 140 additions and 0 deletions
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+/* Copyright (c) 2006-2007 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. */
+
+/**
+ * @requires OpenLayers/Util.js
+ * 
+ * Class: OpenLayers.Projection
+ * Class for coordinate transformations between coordinate systems.
+ *     Depends on the proj4js library. If proj4js is not available, 
+ *     then this is just an empty stub.
+ */
+OpenLayers.Projection = OpenLayers.Class({
+    
+    /**
+     * Constructor: OpenLayers.Projection
+     * This class offers several methods for interacting with a wrapped 
+     *     pro4js projection object. 
+     *
+     * Parameters:
+     * options - {Object} An optional object with properties to set on the
+     *     format
+     *
+     * Returns:
+     * {<OpenLayers.Projection>} A projection object.
+     */
+    initialize: function(projCode, options) {
+        OpenLayers.Util.extend(this, options);
+        this.projCode = projCode;
+        if (window.Proj4js) {
+            this.proj = new Proj4js.Proj(projCode);
+        }
+    },
+    
+    /**
+     * APIMethod: getCode
+     * Get the string SRS code.
+     *
+     * Returns:
+     * {String} The SRS code.
+     */
+    getCode: function() {
+        return this.proj ? this.proj.srsCode : this.projCode;
+    },
+   
+    /**
+     * APIMethod: getUnits
+     * Get the units string for the projection -- returns null if 
+     *     proj4js is not available.
+     *
+     * Returns:
+     * {String} The units abbreviation.
+     */
+    getUnits: function() {
+        return this.proj ? this.proj.units : null;
+    },
+
+    /**
+     * Method: toString
+     * Convert projection to string (getCode wrapper).
+     *
+     * Returns:
+     * {String} The projection code.
+     */
+    toString: function() {
+        return this.getCode();
+    },
+
+    /**
+     * Method: equals
+     * Test equality of two projection instances.  Determines equality based
+     *     soley on the projection code.
+     *
+     * Returns:
+     * {Boolean} The two projections are equivalent.
+     */
+    equals: function(projection) {
+        if (this.getCode() == projection.getCode()) {
+            return true;
+        }
+        return false;
+    },
+
+    /* Method: destroy
+     * Destroy projection object.
+     */
+    destroy: function() {
+        delete this.proj;
+        delete this.projCode;
+    },
+    
+    CLASS_NAME: "OpenLayers.Projection" 
+});     
+
+/**
+ * APIMethod: transform
+ * Read data from a string, and return an object whose type depends on the
+ * subclass. 
+ * 
+ * Parameters:
+ * point - {object} input horizontal coodinate
+ * sourceProj - {OpenLayers.Projection} source map coordinate system
+ * destProj - {OpenLayers.Projection} destination map coordinate system
+ *
+ * Returns:
+ * point - {object} trasnformed coordinate
+ */
+OpenLayers.Projection.transform = function(point, source, dest) {
+    if (source.proj && dest.proj) {
+        point = Proj4js.transform(source.proj, dest.proj, point);
+    }
+    return point;
+};