From 900bc176ae6f69a74e1e171c5219bc121b1d4a8f Mon Sep 17 00:00:00 2001
From: Tom Payne <twpayne@gmail.com>
Date: Tue, 12 Nov 2013 01:26:41 +0100
Subject: [PATCH] Avoid clearing canvas twice

---
 src/ol/renderer/canvas/canvasmaprenderer.js | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/src/ol/renderer/canvas/canvasmaprenderer.js b/src/ol/renderer/canvas/canvasmaprenderer.js
index 769e18e097..9a20c3bedd 100644
--- a/src/ol/renderer/canvas/canvasmaprenderer.js
+++ b/src/ol/renderer/canvas/canvasmaprenderer.js
@@ -95,15 +95,16 @@ ol.renderer.canvas.Map.prototype.renderFrame = function(frameState) {
     return;
   }
 
+  var context = this.context_;
+
   var size = frameState.size;
   if (this.canvas_.width != size[0] || this.canvas_.height != size[1]) {
     this.canvas_.width = size[0];
     this.canvas_.height = size[1];
+  } else {
+    context.clearRect(0, 0, this.canvas_.width, this.canvas_.height);
   }
 
-  var context = this.context_;
-  context.clearRect(0, 0, this.canvas_.width, this.canvas_.height);
-
   this.calculateMatrices2D(frameState);
 
   var layerStates = frameState.layerStates;