7 files changed, 246 insertions, 46 deletions

diff --git a/Server/Prefabs/PieceStructures/NetherFort.cubeset b/Server/Prefabs/PieceStructures/NetherFort.cubeset
index 2fad9d773..ec8496fac 100644
--- a/Server/Prefabs/PieceStructures/NetherFort.cubeset
+++ b/Server/Prefabs/PieceStructures/NetherFort.cubeset
@@ -1773,7 +1773,124 @@ Cubeset =
 			},
 		},  -- BlazePlatformOverhang
 
-
+		{
+			OriginData = 
+			{
+				ExportName = "ClosurePiece",
+			},
+			Size =
+			{
+				x = 5,
+				y = 2,
+				z = 1
+			},
+			Hitbox =
+			{
+				MinX = 0,
+				MinY = 0,
+				MinZ = 0,
+				MaxX = 4,
+				MaxY = 2,
+				MaxZ = 0,
+			},
+			Connectors =
+			{
+				{
+					Type = 0,
+					RelX = 2,
+					RelY = 1,
+					RelZ = 0,
+					Direction = 2,
+				}
+			},
+			Metadata =
+			{
+				["AddWeightIfSame"] = "0",
+				["AllowedRotations"] = "7",
+				["DefaultWeight"] = "100",
+				["DepthWeight"] = "",
+				["ExpandFloorStrategy"] = "none",
+				["IsClosurePiece"] = "1",
+				["MergeStrategy"] = "msSpongePrint",
+				["MoveToGround"] = "0",
+				["VerticalStrategy"] = "Range|40|100",
+			},
+			BlockDefinitions =
+			{
+				".:112:0",
+				"a:113:0",
+			},
+			BlockData =
+			{
+				".....",
+				".aaa.",
+			}
+		}, -- End Piece Connector
+		
+		{
+			OriginData = 
+			{
+				ExportName = "ClosurePiece",
+			},
+			Size =
+			{
+				x = 5,
+				y = 6,
+				z = 1
+			},
+			Hitbox =
+			{
+				MinX = 0,
+				MinY = 0,
+				MinZ = 0,
+				MaxX = 4,
+				MaxY = 4,
+				MaxZ = 0,
+			},
+			Connectors =
+			{
+				{
+					Type = 1,
+					RelX = 2,
+					RelY = 1,
+					RelZ = 0,
+					Direction = 2,
+				},
+				{
+					Type = -1,
+					RelX = 2,
+					RelY = 1,
+					RelZ = 0,
+					Direction = 2,
+				}
+			},
+			Metadata =
+			{
+				["AddWeightIfSame"] = "0",
+				["AllowedRotations"] = "7",
+				["DefaultWeight"] = "100",
+				["DepthWeight"] = "",
+				["ExpandFloorStrategy"] = "RepeatBottomTillSolid",
+				["IsClosurePiece"] = "1",
+				["MergeStrategy"] = "msSpongePrint",
+				["MoveToGround"] = "0",
+				["VerticalStrategy"] = "Range|40|100",
+			},
+			BlockDefinitions =
+			{
+				".:112:0",
+				"a:113:0",
+			},
+			BlockData =
+			{
+				".....",
+				".aaa.",
+				".aaa.",
+				".aaa.",
+				".aaa.",
+				".....",
+			}
+		}, -- End Piece Connector
 
 		{
 			OriginData =
diff --git a/src/Generating/PieceGeneratorBFSTree.cpp b/src/Generating/PieceGeneratorBFSTree.cpp
index 2e26463f2..cf6e82ca3 100644
--- a/src/Generating/PieceGeneratorBFSTree.cpp
+++ b/src/Generating/PieceGeneratorBFSTree.cpp
@@ -101,16 +101,80 @@ bool cPieceGeneratorBFSTree::TryPlacePieceAtConnector(
 	const cPlacedPiece & a_ParentPiece,
 	const cPiece::cConnector & a_Connector,
 	cPlacedPieces & a_OutPieces,
-	cPieceGeneratorBFSTree::cFreeConnectors & a_OutConnectors
+	cPieceGeneratorBFSTree::cFreeConnectors & a_OutConnectors,
+	bool a_OnlyClosurePieces
 )
 {
 	// Get a list of available connections:
 	cConnections Connections;
 	int WantedConnectorType = -a_Connector.m_Type;
-	cPieces AvailablePieces = m_PiecePool.GetPiecesWithConnector(WantedConnectorType);
+	cPieces AvailablePieces;
+	if (a_OnlyClosurePieces)
+	{
+		AvailablePieces = m_PiecePool.GetClosurePiecesWithConnector(WantedConnectorType);
+	}
+	else
+	{
+		AvailablePieces = m_PiecePool.GetPiecesWithConnector(WantedConnectorType);
+	}
 	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
 	int WeightTotal = 0;
+	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.
+		AvailablePieces = m_PiecePool.GetClosurePiecesWithConnector(WantedConnectorType);
+		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);
+
+	// Choose a random connection from the list, based on the weights:
+	int rnd = (m_Noise.IntNoise3DInt(a_Connector.m_Pos.x, a_Connector.m_Pos.y, a_Connector.m_Pos.z) / 7) % WeightTotal;
+	size_t ChosenIndex = 0;
+	for (cConnections::const_iterator itr = Connections.begin(), end = Connections.end(); itr != end; ++itr, ++ChosenIndex)
+	{
+		rnd -= itr->m_Weight;
+		if (rnd <= 0)
+		{
+			// This is the piece to choose
+			break;
+		}
+	}
+	cConnection & Conn = Connections[ChosenIndex];
+
+	// Place the piece:
+	Vector3i NewPos = Conn.m_Piece->RotatePos(Conn.m_Connector.m_Pos, Conn.m_NumCCWRotations);
+	ConnPos -= NewPos;
+	auto PlacedPiece = std::make_unique<cPlacedPiece>(&a_ParentPiece, *(Conn.m_Piece), ConnPos, Conn.m_NumCCWRotations);
+
+	// Add the new piece's connectors to the list of free connectors:
+	cPiece::cConnectors Connectors = Conn.m_Piece->GetConnectors();
+	for (cPiece::cConnectors::const_iterator itr = Connectors.begin(), end = Connectors.end(); itr != end; ++itr)
+	{
+		if (itr->m_Pos.Equals(Conn.m_Connector.m_Pos))
+		{
+			// This is the connector through which we have been connected to the parent, don't add
+			continue;
+		}
+		a_OutConnectors.emplace_back(PlacedPiece.get(), Conn.m_Piece->RotateMoveConnector(*itr, Conn.m_NumCCWRotations, ConnPos.x, ConnPos.y, ConnPos.z));
+	}
+	a_OutPieces.push_back(std::move(PlacedPiece));
+
+	return true;
+}
+
+
+
+
+
+void cPieceGeneratorBFSTree::FindPieceForConnector(cPieces& AvailablePieces, const cPlacedPiece& a_ParentPiece, const cPiece::cConnector& a_Connector, int WantedConnectorType, Vector3i& ConnPos, cPlacedPieces& a_OutPieces, cPieceGeneratorBFSTree::cConnections& Connections, int& WeightTotal)
+{
 	for (cPieces::iterator itrP = AvailablePieces.begin(), endP = AvailablePieces.end(); itrP != endP; ++itrP)
 	{
 		// Get the relative chance of this piece being generated in this path:
@@ -153,46 +217,6 @@ bool cPieceGeneratorBFSTree::TryPlacePieceAtConnector(
 			WeightTotal += Weight;
 		}  // for itrC - Connectors[]
 	}  // for itrP - AvailablePieces[]
-	if (Connections.empty())
-	{
-		// No available connections, bail out
-		return false;
-	}
-	ASSERT(WeightTotal > 0);
-
-	// Choose a random connection from the list, based on the weights:
-	int rnd = (m_Noise.IntNoise3DInt(a_Connector.m_Pos.x, a_Connector.m_Pos.y, a_Connector.m_Pos.z) / 7) % WeightTotal;
-	size_t ChosenIndex = 0;
-	for (cConnections::const_iterator itr = Connections.begin(), end = Connections.end(); itr != end; ++itr, ++ChosenIndex)
-	{
-		rnd -= itr->m_Weight;
-		if (rnd <= 0)
-		{
-			// This is the piece to choose
-			break;
-		}
-	}
-	cConnection & Conn = Connections[ChosenIndex];
-
-	// Place the piece:
-	Vector3i NewPos = Conn.m_Piece->RotatePos(Conn.m_Connector.m_Pos, Conn.m_NumCCWRotations);
-	ConnPos -= NewPos;
-	auto PlacedPiece = std::make_unique<cPlacedPiece>(&a_ParentPiece, *(Conn.m_Piece), ConnPos, Conn.m_NumCCWRotations);
-
-	// Add the new piece's connectors to the list of free connectors:
-	cPiece::cConnectors Connectors = Conn.m_Piece->GetConnectors();
-	for (cPiece::cConnectors::const_iterator itr = Connectors.begin(), end = Connectors.end(); itr != end; ++itr)
-	{
-		if (itr->m_Pos.Equals(Conn.m_Connector.m_Pos))
-		{
-			// This is the connector through which we have been connected to the parent, don't add
-			continue;
-		}
-		a_OutConnectors.emplace_back(PlacedPiece.get(), Conn.m_Piece->RotateMoveConnector(*itr, Conn.m_NumCCWRotations, ConnPos.x, ConnPos.y, ConnPos.z));
-	}
-	a_OutPieces.push_back(std::move(PlacedPiece));
-
-	return true;
 }
 
 
@@ -274,6 +298,10 @@ void cPieceGeneratorBFSTree::PlacePieces(int a_BlockX, int a_BlockZ, int a_MaxDe
 				//*/
 			}
 		}
+		else
+		{
+			TryPlacePieceAtConnector(*Conn.m_Piece, Conn.m_Connector, a_OutPieces, ConnectorPool, true);
+		}
 		NumProcessed++;
 		if (NumProcessed > 1000)
 		{
diff --git a/src/Generating/PieceGeneratorBFSTree.h b/src/Generating/PieceGeneratorBFSTree.h
index 33d2e5350..c7d85c44a 100644
--- a/src/Generating/PieceGeneratorBFSTree.h
+++ b/src/Generating/PieceGeneratorBFSTree.h
@@ -73,9 +73,13 @@ protected:
 		const cPlacedPiece & a_ParentPiece,      // The existing piece to a new piece should be placed
 		const cPiece::cConnector & a_Connector,  // The existing connector (world-coords) to which a new piece should be placed
 		cPlacedPieces & a_OutPieces,             // Already placed pieces, to be checked for intersections
-		cFreeConnectors & a_OutConnectors        // List of free connectors to which the new connectors will be placed
+		cFreeConnectors & a_OutConnectors,        // List of free connectors to which the new connectors will be placed
+		bool a_OnlyClosurePieces = false
 	);
 
+	/** Searches through the provided list for pieces that will fit the parent piece */
+	void FindPieceForConnector(cPieces & AvailablePieces, const cPlacedPiece & a_ParentPiece, const cPiece::cConnector & a_Connector, int WantedConnectorType, Vector3i & ConnPos, cPlacedPieces & a_OutPieces, cPieceGeneratorBFSTree::cConnections & Connections, int & WeightTotal);
+
 	/** Checks if the specified piece would fit with the already-placed pieces, using the specified connector
 	and number of CCW rotations.
 	a_ExistingConnector is in world-coords and is already rotated properly
diff --git a/src/Generating/PiecePool.h b/src/Generating/PiecePool.h
index 5897f32c7..2e027e354 100644
--- a/src/Generating/PiecePool.h
+++ b/src/Generating/PiecePool.h
@@ -284,6 +284,9 @@ 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;
diff --git a/src/Generating/PrefabPiecePool.cpp b/src/Generating/PrefabPiecePool.cpp
index 4deee38ef..b78251d78 100644
--- a/src/Generating/PrefabPiecePool.cpp
+++ b/src/Generating/PrefabPiecePool.cpp
@@ -84,6 +84,11 @@ void cPrefabPiecePool::Clear(void)
 		delete *itr;
 	}
 	m_StartingPieces.clear();
+	for (cPieces::iterator itr = m_ClosurePieces.begin(), end = m_ClosurePieces.end(); itr != end; ++itr)
+	{
+		delete* itr;
+	}
+	m_ClosurePieces.clear();
 }
 
 
@@ -345,8 +350,18 @@ bool cPrefabPiecePool::LoadCubesetPieceVer1(const AString & a_FileName, cLuaStat
 	else
 	{
 		auto p = prefab.release();
-		m_AllPieces.push_back(p);
-		AddToPerConnectorMap(p);
+
+		int IsClosurePiece = 0;
+		a_LuaState.GetNamedValue("Metadata.IsClosurePiece", IsClosurePiece);
+		if (IsClosurePiece != 0)
+		{
+			m_ClosurePieces.push_back(p);
+		}
+		else
+		{
+			m_AllPieces.push_back(p);
+			AddToPerConnectorMap(p);
+		}
 	}
 
 	return true;
@@ -758,6 +773,28 @@ 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())
diff --git a/src/Generating/PrefabPiecePool.h b/src/Generating/PrefabPiecePool.h
index 708b9be57..36aaf8bae 100644
--- a/src/Generating/PrefabPiecePool.h
+++ b/src/Generating/PrefabPiecePool.h
@@ -112,6 +112,7 @@ 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;
@@ -132,6 +133,9 @@ protected:
 	This list is not shared and the pieces need deallocation. */
 	cPieces m_StartingPieces;
 
+	/** The pieces that can be used when no other piece will be placed. */
+	cPieces m_ClosurePieces;
+
 	/** The map that has all pieces by their connector types
 	The pieces are copies out of m_AllPieces and shouldn't be ever delete-d. */
 	cPiecesMap m_PiecesByConnector;
diff --git a/src/Generating/VillageGen.cpp b/src/Generating/VillageGen.cpp
index 6575b2f3a..281d49541 100644
--- a/src/Generating/VillageGen.cpp
+++ b/src/Generating/VillageGen.cpp
@@ -258,6 +258,13 @@ protected:
 	}
 
 
+	virtual cPieces GetClosurePiecesWithConnector(int a_ConnectorType) override
+	{
+		cPieces pieces;
+		return pieces;
+	}
+
+
 	virtual cPieces GetStartingPieces(void) override
 	{
 		return m_Prefabs.GetStartingPieces();