Change "recreate batch" strategy

Only recreate batch when the (buffered) rendered extent contains the **buffered** viewport extent.

src/ol/renderer/canvas/canvasvectorlayerrenderer.js

@@ -180,23 +180,24 @@ ol.renderer.canvas.VectorLayer.prototype.prepareFrame =
   var resolution = viewState.resolution;
   var pixelRatio = frameState.pixelRatio;
   var vectorLayerRevision = vectorLayer.getRevision();
+  var vectorLayerRenderBuffer = vectorLayer.getRenderBuffer();
   var vectorLayerRenderOrder = vectorLayer.getRenderOrder();
+
   if (!goog.isDef(vectorLayerRenderOrder)) {
     vectorLayerRenderOrder = ol.renderer.vector.defaultOrder;
   }
 
+  var extent = ol.extent.buffer(frameStateExtent,
+      vectorLayerRenderBuffer * resolution);
+
   if (!this.dirty_ &&
       this.renderedResolution_ == resolution &&
       this.renderedRevision_ == vectorLayerRevision &&
       this.renderedRenderOrder_ == vectorLayerRenderOrder &&
-      ol.extent.containsExtent(this.renderedExtent_, frameStateExtent)) {
+      ol.extent.containsExtent(this.renderedExtent_, extent)) {
     return true;
   }
 
-  var extent = this.renderedExtent_;
-  var renderBuffer = vectorLayer.getRenderBuffer();
-  ol.extent.buffer(frameStateExtent, renderBuffer * resolution, extent);
-
   // FIXME dispose of old replayGroup in post render
   goog.dispose(this.replayGroup_);
   this.replayGroup_ = null;
@@ -247,6 +248,7 @@ ol.renderer.canvas.VectorLayer.prototype.prepareFrame =
   this.renderedResolution_ = resolution;
   this.renderedRevision_ = vectorLayerRevision;
   this.renderedRenderOrder_ = vectorLayerRenderOrder;
+  this.renderedExtent_ = extent;
   this.replayGroup_ = replayGroup;
 
   return true;

src/ol/renderer/dom/domvectorlayerrenderer.js

@@ -220,23 +220,24 @@ ol.renderer.dom.VectorLayer.prototype.prepareFrame =
   var resolution = viewState.resolution;
   var pixelRatio = frameState.pixelRatio;
   var vectorLayerRevision = vectorLayer.getRevision();
+  var vectorLayerRenderBuffer = vectorLayer.getRenderBuffer();
   var vectorLayerRenderOrder = vectorLayer.getRenderOrder();
+
   if (!goog.isDef(vectorLayerRenderOrder)) {
     vectorLayerRenderOrder = ol.renderer.vector.defaultOrder;
   }
 
+  var extent = ol.extent.buffer(frameStateExtent,
+      vectorLayerRenderBuffer * resolution);
+
   if (!this.dirty_ &&
       this.renderedResolution_ == resolution &&
       this.renderedRevision_ == vectorLayerRevision &&
       this.renderedRenderOrder_ == vectorLayerRenderOrder &&
-      ol.extent.containsExtent(this.renderedExtent_, frameStateExtent)) {
+      ol.extent.containsExtent(this.renderedExtent_, extent)) {
     return true;
   }
 
-  var extent = this.renderedExtent_;
-  var renderBuffer = vectorLayer.getRenderBuffer();
-  ol.extent.buffer(frameStateExtent, renderBuffer * resolution, extent);
-
   // FIXME dispose of old replayGroup in post render
   goog.dispose(this.replayGroup_);
   this.replayGroup_ = null;
@@ -287,6 +288,7 @@ ol.renderer.dom.VectorLayer.prototype.prepareFrame =
   this.renderedResolution_ = resolution;
   this.renderedRevision_ = vectorLayerRevision;
   this.renderedRenderOrder_ = vectorLayerRenderOrder;
+  this.renderedExtent_ = extent;
   this.replayGroup_ = replayGroup;
 
   return true;

src/ol/renderer/webgl/webglvectorlayerrenderer.js

@@ -139,23 +139,24 @@ ol.renderer.webgl.VectorLayer.prototype.prepareFrame =
   var resolution = viewState.resolution;
   var pixelRatio = frameState.pixelRatio;
   var vectorLayerRevision = vectorLayer.getRevision();
+  var vectorLayerRenderBuffer = vectorLayer.getRenderBuffer();
   var vectorLayerRenderOrder = vectorLayer.getRenderOrder();
+
   if (!goog.isDef(vectorLayerRenderOrder)) {
     vectorLayerRenderOrder = ol.renderer.vector.defaultOrder;
   }
 
+  var extent = ol.extent.buffer(frameStateExtent,
+      vectorLayerRenderBuffer * resolution);
+
   if (!this.dirty_ &&
       this.renderedResolution_ == resolution &&
       this.renderedRevision_ == vectorLayerRevision &&
       this.renderedRenderOrder_ == vectorLayerRenderOrder &&
-      ol.extent.containsExtent(this.renderedExtent_, frameStateExtent)) {
+      ol.extent.containsExtent(this.renderedExtent_, extent)) {
     return true;
   }
 
-  var extent = this.renderedExtent_;
-  var renderBuffer = vectorLayer.getRenderBuffer();
-  ol.extent.buffer(frameStateExtent, renderBuffer * resolution, extent);
-
   if (!goog.isNull(this.replayGroup_)) {
     frameState.postRenderFunctions.push(
         this.replayGroup_.getDeleteResourcesFunction(context));
@@ -206,6 +207,7 @@ ol.renderer.webgl.VectorLayer.prototype.prepareFrame =
   this.renderedResolution_ = resolution;
   this.renderedRevision_ = vectorLayerRevision;
   this.renderedRenderOrder_ = vectorLayerRenderOrder;
+  this.renderedExtent_ = extent;
   this.replayGroup_ = replayGroup;
 
   return true;