From f89227fc1a3039937163081b92cbb8d3a66865fb Mon Sep 17 00:00:00 2001
From: Richard Harrison <rjh@zaretto.com>
Date: Mon, 7 Dec 2020 15:12:15 +0100
Subject: [PATCH] Remove mutex lock on realizeTechniques

This was causing a deadlock - and I can't quite remember what problem it was intended to solve so it is best to remove it.
---
 simgear/scene/material/Effect.cxx | 2 --
 1 file changed, 2 deletions(-)

diff --git a/simgear/scene/material/Effect.cxx b/simgear/scene/material/Effect.cxx
index b7eb0b7a..823c61dc 100644
--- a/simgear/scene/material/Effect.cxx
+++ b/simgear/scene/material/Effect.cxx
@@ -1481,10 +1481,8 @@ void mergeSchemesFallbacks(Effect *effect, const SGReaderWriterOptions *options)
 
 // Walk the techniques property tree, building techniques and
 // passes.
-static std::mutex  realizeTechniques_lock;
 bool Effect::realizeTechniques(const SGReaderWriterOptions* options)
 {
-    std::lock_guard<std::mutex> g(realizeTechniques_lock);
     if (getPropertyRoot()->getBoolValue("/sim/version/compositor-support", false))
         mergeSchemesFallbacks(this, options);