/**
 * @name MarkerManager v3
 * @version 1.2
 * @copyright (c) 2007 Google Inc.
 * @author Doug Ricket, Bjorn Brala (port to v3), others,
 *
 * @fileoverview Marker manager is an interface between the map and the user,
 * designed to manage adding and removing many points when the viewport changes.
 * <br /><br />
 * <b>How it Works</b>:<br/> 
 * The MarkerManager places its markers onto a grid, similar to the map tiles.
 * When the user moves the viewport, it computes which grid cells have
 * entered or left the viewport, and shows or hides all the markers in those
 * cells.
 * (If the users scrolls the viewport beyond the markers that are loaded,
 * no markers will be visible until the <code>EVENT_moveend</code> 
 * triggers an update.)
 * In practical consequences, this allows 10,000 markers to be distributed over
 * a large area, and as long as only 100-200 are visible in any given viewport,
 * the user will see good performance corresponding to the 100 visible markers,
 * rather than poor performance corresponding to the total 10,000 markers.
 * Note that some code is optimized for speed over space,
 * with the goal of accommodating thousands of markers.
 */

 
/**
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

 Library Location: http://google-maps-utility-library-v3.googlecode.com/svn/tags/markermanager/