From 885d80ccdb97c984abe85eaeaecf1aedc3e36d25 Mon Sep 17 00:00:00 2001
From: Mattes D <github@xoft.cz>
Date: Thu, 15 Jun 2017 17:06:50 +0200
Subject: [PATCH] Entity: Replaced a mutexed counter with a std::atomic.
 (#3773)

---
 src/Entities/Entity.cpp | 16 +++++++++-------
 src/Entities/Entity.h   | 10 ++++++----
 2 files changed, 15 insertions(+), 11 deletions(-)

diff --git a/src/Entities/Entity.cpp b/src/Entities/Entity.cpp
index 5d26f501b..9ff57602e 100644
--- a/src/Entities/Entity.cpp
+++ b/src/Entities/Entity.cpp
@@ -19,15 +19,21 @@
 
 
 
-UInt32 cEntity::m_EntityCount = 0;
-cCriticalSection cEntity::m_CSCount;
+static UInt32 GetNextUniqueID(void)
+{
+	static std::atomic<UInt32> counter(1);
+	return counter.fetch_add(1);
+}
 
 
 
 
 
+////////////////////////////////////////////////////////////////////////////////
+// cEntity:
+
 cEntity::cEntity(eEntityType a_EntityType, double a_X, double a_Y, double a_Z, double a_Width, double a_Height):
-	m_UniqueID(INVALID_ID),  // Proper ID will be assigned later in the constructor code
+	m_UniqueID(GetNextUniqueID()),
 	m_Health(1),
 	m_MaxHealth(1),
 	m_AttachedTo(nullptr),
@@ -65,10 +71,6 @@ cEntity::cEntity(eEntityType a_EntityType, double a_X, double a_Y, double a_Z, d
 	m_Height(a_Height),
 	m_InvulnerableTicks(0)
 {
-	// Assign a proper ID:
-	cCSLock Lock(m_CSCount);
-	m_EntityCount++;
-	m_UniqueID = m_EntityCount;
 }
 
 
diff --git a/src/Entities/Entity.h b/src/Entities/Entity.h
index b7778e797..4310b1567 100644
--- a/src/Entities/Entity.h
+++ b/src/Entities/Entity.h
@@ -32,7 +32,12 @@
 #define POSZ_TOINT FloorC(GetPosZ())
 #define POS_TOINT  GetPosition().Floor()
 
-#define GET_AND_VERIFY_CURRENT_CHUNK(ChunkVarName, X, Z) cChunk * ChunkVarName = a_Chunk.GetNeighborChunk(X, Z); if ((ChunkVarName == nullptr) || !ChunkVarName->IsValid()) { return; }
+#define GET_AND_VERIFY_CURRENT_CHUNK(ChunkVarName, X, Z) \
+	cChunk * ChunkVarName = a_Chunk.GetNeighborChunk(X, Z); \
+	if ((ChunkVarName == nullptr) || !ChunkVarName->IsValid()) \
+	{ \
+		return; \
+	}
 
 
 
@@ -518,9 +523,6 @@ protected:
 		bool m_ShouldPreventTeleportation;
 	};
 
-	static cCriticalSection m_CSCount;
-	static UInt32 m_EntityCount;
-
 	/** Measured in meters / second (m / s) */
 	Vector3d m_Speed;