New vector rendering for better performance and less renderer specific limitations. r=elemoine (closes #1675, closes #1656, closes #1631, closes #1431, closes #1709)

git-svn-id: http://svn.openlayers.org/trunk/openlayers@7930 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Layer/Vector.js

@@ -106,6 +106,13 @@ OpenLayers.Layer.Vector = OpenLayers.Class(OpenLayers.Layer, {
      * {Array(<OpenLayers.Feature.Vector>)} 
      */
     selectedFeatures: null,
+    
+    /**
+     * Property: unrenderedFeatures
+     * {Object} hash of features, keyed by feature.id, that the renderer
+     *     failed to draw
+     */
+    unrenderedFeatures: null,
 
     /**
      * APIProperty: reportError
@@ -213,6 +220,7 @@ OpenLayers.Layer.Vector = OpenLayers.Class(OpenLayers.Layer, {
 
         this.features = [];
         this.selectedFeatures = [];
+        this.unrenderedFeatures = {};
         
         // Allow for custom layer behavior
         if(this.strategies){
@@ -247,6 +255,7 @@ OpenLayers.Layer.Vector = OpenLayers.Class(OpenLayers.Layer, {
         this.destroyFeatures();
         this.features = null;
         this.selectedFeatures = null;
+        this.unrenderedFeatures = null;
         if (this.renderer) {
             this.renderer.destroy();
         }
@@ -359,6 +368,8 @@ OpenLayers.Layer.Vector = OpenLayers.Class(OpenLayers.Layer, {
      */
     moveTo: function(bounds, zoomChanged, dragging) {
         OpenLayers.Layer.prototype.moveTo.apply(this, arguments);
+        
+        var coordSysUnchanged = true;
 
         if (!dragging) {
             this.renderer.root.style.visibility = "hidden";
@@ -366,7 +377,7 @@ OpenLayers.Layer.Vector = OpenLayers.Class(OpenLayers.Layer, {
             this.div.style.left = -parseInt(this.map.layerContainerDiv.style.left) + "px";
             this.div.style.top = -parseInt(this.map.layerContainerDiv.style.top) + "px";
             var extent = this.map.getExtent();
-            this.renderer.setExtent(extent);
+            coordSysUnchanged = this.renderer.setExtent(extent, zoomChanged);
             
             this.renderer.root.style.visibility = "visible";
 
@@ -376,17 +387,33 @@ OpenLayers.Layer.Vector = OpenLayers.Class(OpenLayers.Layer, {
             if (navigator.userAgent.toLowerCase().indexOf("gecko") != -1) {
                 this.div.scrollLeft = this.div.scrollLeft;
             }
+            
+            if(!zoomChanged && coordSysUnchanged) {
+                var unrenderedFeatures = {};
+                for(var i in this.unrenderedFeatures) {
+                    var feature = this.unrenderedFeatures[i];
+                    if(!this.drawFeature(feature)) {
+                        unrenderedFeatures[i] = feature;
+                    }
+                }
+                this.unrenderedFeatures = unrenderedFeatures;
+            }
         }
         
-        if (!this.drawn || zoomChanged) {
+        if (!this.drawn || zoomChanged || !coordSysUnchanged) {
+            this.unrenderedFeatures = {};
             this.drawn = true;
+            var feature;
             for(var i=0, len=this.features.length; i<len; i++) {
                 if (i != (this.features.length - 1)) {
                     this.renderer.locked = true;
                 } else {
                     this.renderer.locked = false;
                 }    
-                this.drawFeature(this.features[i]);
+                feature = this.features[i];
+                if (!this.drawFeature(feature)) {
+                    this.unrenderedFeatures[feature.id] = feature;
+                };
             }
         }    
     },
@@ -438,7 +465,9 @@ OpenLayers.Layer.Vector = OpenLayers.Class(OpenLayers.Layer, {
             }
 
             if (this.drawn) {
-                this.drawFeature(feature);
+                if(!this.drawFeature(feature)) {
+                    this.unrenderedFeatures[feature.id] = feature;
+                }
             }
             
             if (notify) {
@@ -488,6 +517,7 @@ OpenLayers.Layer.Vector = OpenLayers.Class(OpenLayers.Layer, {
             }
     
             var feature = features[i];
+            delete this.unrenderedFeatures[feature.id];
 
             if (notify) {
                 this.events.triggerEvent("beforefeatureremoved", {
@@ -553,6 +583,10 @@ OpenLayers.Layer.Vector = OpenLayers.Class(OpenLayers.Layer, {
      * Parameters: 
      * feature - {<OpenLayers.Feature.Vector>} 
      * style - {Object} Symbolizer hash or {String} renderIntent
+     * 
+     * Returns:
+     * {Boolean} true if the renderer was able to draw the feature, false
+     *     otherwise
      */
     drawFeature: function(feature, style) {
         if (typeof style != "object") {
@@ -564,7 +598,7 @@ OpenLayers.Layer.Vector = OpenLayers.Class(OpenLayers.Layer, {
             }
         }
         
-        this.renderer.drawFeature(feature, style);
+        return this.renderer.drawFeature(feature, style);
     },
     
     /**