From af809ab210182c371828b80d192e58c31cb4568f Mon Sep 17 00:00:00 2001
From: Bart van Strien <bart@bartbes.ath.cx>
Date: Sun, 15 May 2011 22:10:17 +0200
Subject: [PATCH] Switch to bitwise ops to po2ify

---
 src/modules/image/devil/ImageData.cpp | 16 ++++++++++++++--
 1 file changed, 14 insertions(+), 2 deletions(-)

diff --git a/src/modules/image/devil/ImageData.cpp b/src/modules/image/devil/ImageData.cpp
index 34c235b1a..99a46b2e5 100644
--- a/src/modules/image/devil/ImageData.cpp
+++ b/src/modules/image/devil/ImageData.cpp
@@ -27,6 +27,18 @@
 #include <common/Exception.h>
 #include <filesystem/File.h>
 
+int toPo2(int n)
+{
+	n -= 1;
+	n |= n >> 1;
+	n |= n >> 2;
+	n |= n >> 4;
+	n |= n >> 8;
+	n |= n >> 16;
+	n |= n >> 32;
+	return n+1;
+}
+
 namespace love
 {
 namespace image
@@ -42,8 +54,8 @@ namespace devil
 		ilBindImage(image);
 
 		//scale to nearest bigger po2
-		width = pow(2, ceil(log((double) width)/log(2.0)));
-		height = pow(2, ceil(log((double) height)/log(2.0)));
+		width = toPo2(width);
+		height = toPo2(height);
 
 		//create and populate the image
 		bool success = (ilTexImage(width, height, 1, bpp, IL_RGBA, IL_UNSIGNED_BYTE, data) == IL_TRUE);