Adjust redraw. Before, we were appending the marker again -- but there's no reason to do that. The markers already exist, we're adjusting their position anyway. This should result in a 2/3rds speed win after the initial display, because appendChild was the largest length of time in the entire redraw process.

git-svn-id: http://svn.openlayers.org/trunk/openlayers@267 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Layer/Marker.js

@@ -44,24 +44,11 @@ OpenLayers.Layer.Marker.prototype =
     *    Use the map to recalculate new placement of markers.
     */
     redraw: function() {
-
-        this.clear();
         for(i=0; i < this.markers.length; i++) {
             this.drawMarker(this.markers[i]);
         }
-
     },
 
-    /** This function clears the visual display of the markers, without
-    *    removing them from memory (this.markers array). 
-    *
-    * @private
-    */
-    clear: function() {
-        this.div.innerHTML = "";
-    },
-
-
     /** Calculate the screen pixel location for the marker, create it, and 
     *    add it to the layer's div
     * 
@@ -72,7 +59,10 @@ OpenLayers.Layer.Marker.prototype =
     drawMarker: function(marker) {
         var px = this.map.getPixelFromLonLat(marker.lonlat);
         var markerDiv = marker.draw(px);
-        this.div.appendChild(markerDiv);
+        if (marker.drawn != 1) {
+            this.div.appendChild(markerDiv);
+            marker.drawn = 1;
+        }
     },
     
     /** @final @type String */