From 2713addb333f0063cf83e5769507f97a8df19b2d Mon Sep 17 00:00:00 2001
From: Tom Payne <twpayne@gmail.com>
Date: Fri, 28 Sep 2012 20:05:01 +0200
Subject: [PATCH] More accurate WebGL support test, see issue #31

---
 src/ol/renderer/webgl/webgl.js | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/ol/renderer/webgl/webgl.js b/src/ol/renderer/webgl/webgl.js
index 782b2b695e..23e221e2ee 100644
--- a/src/ol/renderer/webgl/webgl.js
+++ b/src/ol/renderer/webgl/webgl.js
@@ -11,5 +11,9 @@ ol.renderer.webgl.FREE_RESOURCES_IMMEDIATELY = false;
  * @return {boolean} Is supported.
  */
 ol.renderer.webgl.isSupported = function() {
-  return 'WebGLRenderingContext' in goog.global;
+  if (!('WebGLRenderingContext' in goog.global)) {
+    return false;
+  }
+  var canvas = goog.dom.createElement(goog.dom.TagName.CANVAS);
+  return !goog.isNull(canvas.getContext('experimental-webgl'));
 };