added getZoomForResolution() to map & layer. partial fix for #204 -- need to make a getZoomForResolution() for OpenLayers.Layer.FixedZoomLevels

git-svn-id: http://svn.openlayers.org/trunk/openlayers@1382 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Layer.js

@@ -375,9 +375,22 @@ OpenLayers.Layer.prototype = {
         var viewSize = this.map.getSize();
         var idealResolution = Math.max( extent.getWidth()  / viewSize.w,
                                         extent.getHeight() / viewSize.h );
+
+        return this.getZoomForResolution(idealResolution);
+    },
+    
+    /**
+     * @param {float} resolution
+     *
+     * @returns The index of the zoomLevel (entry in the resolutions array) 
+     *           that is the smallest resolution that is greater than the 
+     *           passed-in resolution.
+     * @type int
+     */
+    getZoomForResolution: function(resolution) {
         
         for(var i=1; i <= this.resolutions.length; i++) {
-            if ( this.resolutions[i] < idealResolution) {
+            if ( this.resolutions[i] < resolution) {
                 break;
             }
         }

lib/OpenLayers/Map.js

@@ -781,12 +781,12 @@ OpenLayers.Map.prototype = {
 
 
     /**
-    * @param {OpenLayers.Bounds} bounds
+     * @param {OpenLayers.Bounds} bounds
-    *
+     *
-    * @returns A suitable zoom level for the specified bounds.
+     * @returns A suitable zoom level for the specified bounds.
-    *          If no baselayer is set, returns null.
+     *          If no baselayer is set, returns null.
-    * @type int
+     * @type int
-    */
+     */
     getZoomForExtent: function (bounds) {
         zoom = null;
         if (this.baseLayer != null) {
@@ -795,6 +795,21 @@ OpenLayers.Map.prototype = {
         return zoom;
     },
 
+    /**
+     * @param {float} resolution
+     *
+     * @returns A suitable zoom level for the specified resolution.
+     *          If no baselayer is set, returns null.
+     * @type int
+     */
+    getZoomForResolution: function(resolution) {
+        zoom = null;
+        if (this.baseLayer != null) {
+            zoom = this.baseLayer.getZoomForResolution(resolution);
+        }
+        return zoom;
+    },
+
   /********************************************************/
   /*                                                      */
   /*                  Zooming Functions                   */