From eb3c8a8bfce00309ddcfb266341e6a498ff8dcd9 Mon Sep 17 00:00:00 2001
From: Tom Payne <twpayne@gmail.com>
Date: Thu, 16 Jan 2014 15:36:27 +0100
Subject: [PATCH 1/2] Remember rendered revision in ol.source.ImageCanvas

---
 src/ol/source/imagecanvassource.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/ol/source/imagecanvassource.js b/src/ol/source/imagecanvassource.js
index 221104d822..30abfbf469 100644
--- a/src/ol/source/imagecanvassource.js
+++ b/src/ol/source/imagecanvassource.js
@@ -35,6 +35,12 @@ ol.source.ImageCanvas = function(options) {
    */
   this.canvas_ = null;
 
+  /**
+   * @private
+   * @type {number}
+   */
+  this.renderedRevision_ = 0;
+
   /**
    * @private
    * @type {number}
@@ -55,6 +61,7 @@ ol.source.ImageCanvas.prototype.getImage =
 
   var canvas = this.canvas_;
   if (!goog.isNull(canvas) &&
+      this.renderedRevision_ == this.getRevision() &&
       canvas.getResolution() == resolution &&
       canvas.getPixelRatio() == pixelRatio &&
       ol.extent.containsExtent(canvas.getExtent(), extent)) {
@@ -74,6 +81,7 @@ ol.source.ImageCanvas.prototype.getImage =
         this.getAttributions(), canvasElement);
   }
   this.canvas_ = canvas;
+  this.renderedRevision_ = this.getRevision();
 
   return canvas;
 };

From 27ad19a6137693b90f0e32df3672fc2de6ae290e Mon Sep 17 00:00:00 2001
From: Tom Payne <twpayne@gmail.com>
Date: Thu, 16 Jan 2014 18:27:45 +0100
Subject: [PATCH 2/2] Remember rendered revision in ol.source.ImageWMS

---
 src/ol/source/imagewmssource.js | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/src/ol/source/imagewmssource.js b/src/ol/source/imagewmssource.js
index 8866368d48..82a7c2348e 100644
--- a/src/ol/source/imagewmssource.js
+++ b/src/ol/source/imagewmssource.js
@@ -74,6 +74,12 @@ ol.source.ImageWMS = function(opt_options) {
    */
   this.image_ = null;
 
+  /**
+   * @private
+   * @type {number}
+   */
+  this.renderedRevision_ = 0;
+
   /**
    * @private
    * @type {number}
@@ -112,6 +118,7 @@ ol.source.ImageWMS.prototype.getImage =
 
   var image = this.image_;
   if (!goog.isNull(image) &&
+      this.renderedRevision_ == this.getRevision() &&
       image.getResolution() == resolution &&
       image.getPixelRatio() == pixelRatio &&
       ol.extent.containsExtent(image.getExtent(), extent)) {
@@ -190,6 +197,7 @@ ol.source.ImageWMS.prototype.getImage =
 
   this.image_ = new ol.Image(extent, resolution, pixelRatio,
       this.getAttributions(), url, this.crossOrigin_);
+  this.renderedRevision_ = this.getRevision();
   return this.image_;
 
 };