From bf6705a80d1faa4231bb9dd4627eab9c49f7ca9f Mon Sep 17 00:00:00 2001
From: Tom Payne <twpayne@gmail.com>
Date: Mon, 6 Aug 2012 00:00:38 +0200
Subject: [PATCH] Improve algorithm for finding framebuffer size

---
 src/ol/webgl/tilelayerrenderer.js | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/src/ol/webgl/tilelayerrenderer.js b/src/ol/webgl/tilelayerrenderer.js
index 060eb237cc..6e31d0b4d2 100644
--- a/src/ol/webgl/tilelayerrenderer.js
+++ b/src/ol/webgl/tilelayerrenderer.js
@@ -269,11 +269,8 @@ ol.webgl.TileLayerRenderer.prototype.render = function() {
   var maxDimension = Math.max(
       tileBoundsSize.width * tileSize.width,
       tileBoundsSize.height * tileSize.height);
-  // FIXME find a better algorithms for rounding up to the next power of two
-  var framebufferDimension = Math.max(tileSize.width, tileSize.height);
-  while (framebufferDimension < maxDimension) {
-    framebufferDimension *= 2;
-  }
+  var framebufferDimension =
+      Math.pow(2, Math.ceil(Math.log(maxDimension) / Math.log(2)));
   var nTilesX = framebufferDimension / tileSize.width;
   var nTilesY = framebufferDimension / tileSize.height;
   var framebufferTileBounds = new ol.TileBounds(