From 0df5fe8705fe1270616ca4dfd1456e1e45f3ed61 Mon Sep 17 00:00:00 2001
From: Alexander van Gessel <ai0867@gmail.com>
Date: Sun, 5 Nov 2017 15:17:07 +0100
Subject: [PATCH] Properly size circular buffer

In most cases, it should now use less memory and be faster to construct.
In the other cases, blurring used to be incorrect because the buffer was too small.
---
 src/sdl/utils.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/sdl/utils.cpp b/src/sdl/utils.cpp
index 46103a1dfadc..b5d19cd445b0 100644
--- a/src/sdl/utils.cpp
+++ b/src/sdl/utils.cpp
@@ -1603,7 +1603,7 @@ surface blur_alpha_surface(const surface &surf, int depth)
 		depth = max_blur;
 	}
 
-	boost::circular_buffer<Uint32> queue(max_blur);
+	boost::circular_buffer<Uint32> queue(depth*2+1);
 
 	const Uint32 ff = 0xff;