Instead of explicit closure pieces try to place pieces with a single connector.

src/Generating/PieceGeneratorBFSTree.cpp

@@ -108,14 +108,33 @@ bool cPieceGeneratorBFSTree::TryPlacePieceAtConnector(
 	// Get a list of available connections:
 	cConnections Connections;
 	int WantedConnectorType = -a_Connector.m_Type;
-	cPieces AvailablePieces;
+	cPieces AvailablePieces = m_PiecePool.GetPiecesWithConnector(WantedConnectorType);
 	if (a_OnlyClosurePieces)
 	{
-		AvailablePieces = m_PiecePool.GetClosurePiecesWithConnector(WantedConnectorType);
+		cPieces closurePieces;
-	}
+		closurePieces.reserve(AvailablePieces.size());
-	else
+		for (auto & piece : AvailablePieces)
-	{
+		{
-		AvailablePieces = m_PiecePool.GetPiecesWithConnector(WantedConnectorType);
+			auto hitBox = piece->GetHitBox();
+			hitBox.Sort();
+			auto pieceSize = hitBox.p2 - hitBox.p1;
+			auto connectors = piece->GetConnectors();
+			Vector3i lastCoord = connectors[0].m_Pos;
+			bool hasMultipleConnectors = false;
+			for (const auto & connector : connectors)
+			{
+				if (connector.m_Pos != lastCoord)
+				{
+					hasMultipleConnectors = true;
+					break;
+				}
+			}
+			if (!hasMultipleConnectors)
+			{
+				closurePieces.push_back(piece);
+			}
+		}
+		AvailablePieces = closurePieces;
 	}
 	Connections.reserve(AvailablePieces.size());
 	Vector3i ConnPos = cPiece::cConnector::AddDirection(a_Connector.m_Pos, a_Connector.m_Direction);  // The position at which the new connector should be placed - 1 block away from the current connector
@@ -123,14 +142,8 @@ bool cPieceGeneratorBFSTree::TryPlacePieceAtConnector(
 	FindPieceForConnector(AvailablePieces, a_ParentPiece, a_Connector, WantedConnectorType, ConnPos, a_OutPieces, Connections, WeightTotal);
 	if (Connections.empty())
 	{
-		// If there are no available connections try to place a closure connector.
+		// No available connections, bail out
-		AvailablePieces = m_PiecePool.GetClosurePiecesWithConnector(WantedConnectorType);
+		return false;
-		FindPieceForConnector(AvailablePieces, a_ParentPiece, a_Connector, WantedConnectorType, ConnPos, a_OutPieces, Connections, WeightTotal);
-		if (Connections.empty())
-		{
-			// No available connections, bail out
-			return false;
-		}
 	}
 	ASSERT(WeightTotal > 0);
 

src/Generating/PiecePool.h

@@ -284,9 +284,6 @@ public:
 	The cPiece pointers returned are managed by the pool and the caller doesn't free them. */
 	virtual cPieces GetPiecesWithConnector(int a_ConnectorType) = 0;
 
-	/** Returns a list of closure pieces that contain the specified connector type. */
-	virtual cPieces GetClosurePiecesWithConnector(int a_ConnectorType) = 0;
-
 	/** Returns the pieces that should be used as the starting point.
 	Multiple starting points are supported, one of the returned piece will be chosen. */
 	virtual cPieces GetStartingPieces(void) = 0;

src/Generating/PrefabPiecePool.cpp

@@ -350,18 +350,8 @@ bool cPrefabPiecePool::LoadCubesetPieceVer1(const AString & a_FileName, cLuaStat
 	else
 	{
 		auto p = prefab.release();
-
+		m_AllPieces.push_back(p);
-		int IsClosurePiece = 0;
+		AddToPerConnectorMap(p);
-		a_LuaState.GetNamedValue("Metadata.IsClosurePiece", IsClosurePiece);
-		if (IsClosurePiece != 0)
-		{
-			m_ClosurePieces.push_back(p);
-		}
-		else
-		{
-			m_AllPieces.push_back(p);
-			AddToPerConnectorMap(p);
-		}
 	}
 
 	return true;
@@ -773,28 +763,6 @@ cPieces cPrefabPiecePool::GetPiecesWithConnector(int a_ConnectorType)
 
 
 
-cPieces cPrefabPiecePool::GetClosurePiecesWithConnector(int a_ConnectorType)
-{
-	cPieces pieces;
-	for (auto& piece : m_ClosurePieces)
-	{
-		auto connectors = piece->GetConnectors();
-		for (auto& connector : connectors)
-		{
-			if (connector.m_Type == a_ConnectorType)
-			{
-				pieces.push_back(piece);
-				break;
-			}
-		}
-	}
-	return pieces;
-}
-
-
-
-
-
 cPieces cPrefabPiecePool::GetStartingPieces(void)
 {
 	if (m_StartingPieces.empty())

src/Generating/PrefabPiecePool.h

@@ -112,7 +112,6 @@ public:
 
 	// cPiecePool overrides:
 	virtual cPieces GetPiecesWithConnector(int a_ConnectorType) override;
-	virtual cPieces GetClosurePiecesWithConnector(int a_ConnectorType) override;
 	virtual cPieces GetStartingPieces(void) override;
 	virtual int GetPieceWeight(const cPlacedPiece & a_PlacedPiece, const cPiece::cConnector & a_ExistingConnector, const cPiece & a_NewPiece) override;
 	virtual int GetStartingPieceWeight(const cPiece & a_NewPiece) override;

src/Generating/VillageGen.cpp

@@ -258,13 +258,6 @@ protected:
 	}
 
 
-	virtual cPieces GetClosurePiecesWithConnector(int a_ConnectorType) override
-	{
-		cPieces pieces;
-		return pieces;
-	}
-
-
 	virtual cPieces GetStartingPieces(void) override
 	{
 		return m_Prefabs.GetStartingPieces();