From 21ab556d2fefbaa1a6434d6f82ab079f953e9f44 Mon Sep 17 00:00:00 2001
From: Tom Payne <twpayne@gmail.com>
Date: Thu, 4 Oct 2012 11:14:46 +0200
Subject: [PATCH] Cope with layers being undefined

---
 src/ol/renderer/map.js | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/ol/renderer/map.js b/src/ol/renderer/map.js
index b0ed2ce188..1b009953a5 100644
--- a/src/ol/renderer/map.js
+++ b/src/ol/renderer/map.js
@@ -141,12 +141,14 @@ ol.renderer.Map.prototype.disposeInternal = function() {
  */
 ol.renderer.Map.prototype.forEachReadyVisibleLayer = function(f, opt_obj) {
   var layers = this.map.getLayers();
-  layers.forEach(function(layer, index) {
-    if (layer.isReady() && layer.getVisible()) {
-      var layerRenderer = this.getLayerRenderer(layer);
-      f.call(opt_obj, layer, layerRenderer, index);
-    }
-  }, this);
+  if (goog.isDef(layers)) {
+    layers.forEach(function(layer, index) {
+      if (layer.isReady() && layer.getVisible()) {
+        var layerRenderer = this.getLayerRenderer(layer);
+        f.call(opt_obj, layer, layerRenderer, index);
+      }
+    }, this);
+  }
 };