From f75142213bf9c3959a91aa578902331b77af3f18 Mon Sep 17 00:00:00 2001
From: zeromus <zeromus@zeromus.org>
Date: Tue, 3 Jun 2014 03:09:43 +0000
Subject: [PATCH] make lua surface clearing more robust

---
 .../DisplayManager/DisplayManager.cs           | 18 ++++++++++++++++--
 1 file changed, 16 insertions(+), 2 deletions(-)

diff --git a/BizHawk.Client.EmuHawk/DisplayManager/DisplayManager.cs b/BizHawk.Client.EmuHawk/DisplayManager/DisplayManager.cs
index c940a4867e..330695f772 100644
--- a/BizHawk.Client.EmuHawk/DisplayManager/DisplayManager.cs
+++ b/BizHawk.Client.EmuHawk/DisplayManager/DisplayManager.cs
@@ -524,6 +524,16 @@ TESTEROO:
 		SwappableDisplaySurfaceSet luaNativeSurfaceSet = new SwappableDisplaySurfaceSet();
 		public void SetLuaSurfaceNativePreOSD(DisplaySurface surface) { luaNativeSurfaceSet.SetPending(surface); }
 
+		/// <summary>
+		/// Peeks a locked lua surface, or returns null if it isnt locked
+		/// </summary>
+		public DisplaySurface PeekLockedLuaSurface(string name)
+		{
+			if (MapNameToLuaSurface.ContainsKey(name))
+				return MapNameToLuaSurface[name];
+			return null;
+		}
+
 		/// <summary>
 		/// Locks the requested lua surface name
 		/// </summary>
@@ -558,9 +568,13 @@ TESTEROO:
 		{
 			foreach (var kvp in LuaSurfaceSets)
 			{
-				var surf = LockLuaSurface(kvp.Key);
+				var surf = PeekLockedLuaSurface(kvp.Key);
+				DisplaySurface surfLocked = null;
+				if (surf == null)
+					surf = surfLocked = LockLuaSurface(kvp.Key);
 				surf.Clear();
-				UnlockLuaSurface(surf);
+				if(surfLocked != null)
+					UnlockLuaSurface(surfLocked);
 				LuaSurfaceSets[kvp.Key].SetPending(null);
 			}
 		}