1 files changed, 335 insertions, 0 deletions

diff --git a/src/Generating/PiecePool.h b/src/Generating/PiecePool.h
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+// PiecePool.h
+
+// Declares the cPiecePool class representing a pool of cPieces - "parts" of a structure, used in piece-generators
+
+
+
+
+
+#pragma once
+
+#include "ComposableGenerator.h"
+#include "../Defines.h"
+#include "../Cuboid.h"
+
+
+
+
+
+/** Represents a single piece. Can have multiple connectors of different types where other pieces can connect. */
+class cPiece
+{
+public:
+	// Force a virtual destructor in all descendants
+	virtual ~cPiece() {}
+
+	struct cConnector
+	{
+		enum eDirection
+		{
+			// The following values correspond to equivalent eBlockFace values:
+			dirXM   =  BLOCK_FACE_XM,  // Pointing towards the X- side of the prefab
+			dirXP   =  BLOCK_FACE_XP,  // Pointing towards the X+ side of the prefab
+			dirYM   =  BLOCK_FACE_YM,  // Pointing towards the Y- side of the prefab, doesn't change with rotation around the Y axis
+			dirYP   =  BLOCK_FACE_YP,  // Pointing towards the Y+ side of the prefab, doesn't change with rotation around the Y axis
+			dirZM   =  BLOCK_FACE_ZM,  // Pointing towards the Z- side of the prefab
+			dirZP   =  BLOCK_FACE_ZP,  // Pointing towards the Z+ side of the prefab
+
+			// Special kind of the vertical connectors (changes with rotation around the Y axis)
+			dirYM_XM_ZM = BLOCK_FACE_MAX + 1,  // Pointing towards the Y- side of the prefab, conceptually at the X- Z- corner of the block
+			dirYM_XM_ZP,                       // Pointing towards the Y- side of the prefab, conceptually at the X- Z+ corner of the block
+			dirYM_XP_ZM,                       // Pointing towards the Y- side of the prefab, conceptually at the X+ Z- corner of the block
+			dirYM_XP_ZP,                       // Pointing towards the Y- side of the prefab, conceptually at the X+ Z+ corner of the block
+			dirYP_XM_ZM,                       // Pointing towards the Y+ side of the prefab, conceptually at the X- Z- corner of the block
+			dirYP_XM_ZP,                       // Pointing towards the Y+ side of the prefab, conceptually at the X- Z+ corner of the block
+			dirYP_XP_ZM,                       // Pointing towards the Y+ side of the prefab, conceptually at the X+ Z- corner of the block
+			dirYP_XP_ZP,                       // Pointing towards the Y+ side of the prefab, conceptually at the X+ Z+ corner of the block
+		};
+
+		/** Position relative to the piece */
+		Vector3i m_Pos;
+
+		/** Type of the connector. Any arbitrary number; the generator connects only connectors of opposite
+		(negative) types. */
+		int m_Type;
+
+		/** Direction in which the connector is facing.
+		Will be matched by the opposite direction for the connecting connector. */
+		eDirection m_Direction;
+
+		cConnector(int a_X, int a_Y, int a_Z, int a_Type, eDirection a_Direction);
+		cConnector(const Vector3i & a_Pos, int a_Type, eDirection a_Direction);
+
+		/** Returns the position of the block that has the specified direction from the specified position.
+		Similar to ::AddFaceDirection() */
+		static Vector3i AddDirection(const Vector3i & a_Pos, eDirection a_Direction);
+
+		/** Returns the string representation of the direction.
+		For debugging purposes. */
+		static const char * DirectionToString(eDirection a_Direction);
+
+		/** Returns true if the specified number corresponds to a valid eDirection. */
+		static bool IsValidDirection(int a_Direction);
+
+		/** Returns the direction corresponding to the given direction rotated 180 degrees around the Y axis. */
+		static eDirection RotateDirection(eDirection a_Direction);
+
+		/** Returns the direction corresponding to the given direction rotated 90 degrees CCW around the Y axis. */
+		static eDirection RotateDirectionCCW(eDirection a_Direction);
+
+		/** Returns the direction corresponding to the given direction rotated 90 degrees CW around the Y axis. */
+		static eDirection RotateDirectionCW(eDirection a_Direction);
+
+		/** Returns the number of CCW rotations that a_RotatingDir requires in order to be the counter-direction of a_FixedDir.
+		Ie. if you have a connector with a_FixedDir and you're rotating a piece that has a connector with a_RotatingDir,
+		how many CCW rotations it needs to make the connectors compatible.
+		Returns -1 if it is impossible to fit the two directions. */
+		static int GetNumCCWRotationsToFit(eDirection a_FixedDir, eDirection a_RotatingDir);
+
+		/** Converts the string representation of a direction into the eDirection enum value.
+		Returns true if successful, false on failure.
+		Accepts both numbers and string representations such as "x+" or "Y+X-Z+". */
+		static bool StringToDirection(const AString & a_Value, eDirection & a_Out);
+	};
+
+	typedef std::vector<cConnector> cConnectors;
+
+
+	/** Base class (interface) for strategies for placing the starting pieces vertically.
+	Descendants can override the GetVerticalPlacement() method to provide custom placement decisions. */
+	class cVerticalStrategy
+	{
+	public:
+		// Force a virtual destructor in descendants
+		virtual ~cVerticalStrategy() {}
+
+		/** Returns the Y coord of the piece */
+		virtual int GetVerticalPlacement(int a_BlockX, int a_BlockZ) = 0;
+
+		/** Initializes the strategy's parameters from the string representation.
+		a_Params is the string containing only the parameters (substring after the first pipe character in the strategy description string).
+		If a_LogWarnings is true, logs any problems to the console.
+		Returns true if successful, false if the string parsing failed.
+		Used when loading the strategy from a file. */
+		virtual bool InitializeFromString(const AString & a_Params, bool a_LogWarnings) = 0;
+
+		/** Called when the piece pool is assigned to a generator,
+		so that the strategies may bind to the underlying subgenerators. */
+		virtual void AssignGens(int a_Seed, cBiomeGenPtr & a_BiomeGen, cTerrainHeightGenPtr & a_TerrainHeightGen, int a_SeaLevel) {}
+	};
+
+	typedef SharedPtr<cVerticalStrategy> cVerticalStrategyPtr;
+
+
+	/** Base class (interface) for the vertical limit of piece placement.
+	Each placed piece can have a limit, represented by this class, that gets queried for validity of the placement. */
+	class cVerticalLimit
+	{
+	public:
+		virtual ~cVerticalLimit() {}
+
+		/** Called to inquire whether the specified piece can be placed at the specified height.
+		a_BlockX, a_BlockZ is the column of the connector that is being queried.
+		a_Height is the requested height of the piece's lowest block. */
+		virtual bool CanBeAtHeight(int a_BlockX, int a_BlockZ, int a_Height) = 0;
+
+		/** Initializes the limit's parameters from the string representation.
+		a_Params is the string containing only the parameters (substring after the first pipe character in the limit description string).
+		Returns true if successful, false if the string parsing failed.
+		If a_LogWarnings is true, any error while parsing the string is output to the server console.
+		Used when loading the limit from a file. */
+		virtual bool InitializeFromString(const AString & a_Params, bool a_LogWarnings) = 0;
+
+		/** Called when the piece pool is assigned to a generator,
+		so that the limits may bind to the underlying subgenerators. */
+		virtual void AssignGens(int a_Seed, cBiomeGenPtr & a_BiomeGen, cTerrainHeightGenPtr & a_TerrainHeightGen, int a_SeaLevel) {}
+	};
+
+	typedef SharedPtr<cVerticalLimit> cVerticalLimitPtr;
+
+
+	/** The strategy used for vertical placement of this piece when it is used as a starting piece. */
+	cVerticalStrategyPtr m_VerticalStrategy;
+
+	/** The checker that verifies each placement's vertical position. */
+	cVerticalLimitPtr m_VerticalLimit;
+
+
+	/** Returns all of the available connectors that the piece has.
+	Each connector has a (relative) position in the piece, and a type associated with it. */
+	virtual cConnectors GetConnectors(void) const = 0;
+
+	/** Returns the dimensions of this piece.
+	The dimensions cover the entire piece, there is no block that the piece generates outside of this size. */
+	virtual Vector3i GetSize(void) const = 0;
+
+	/** Returns the "hitbox" of this piece.
+	A hitbox is what is compared and must not intersect other pieces' hitboxes when generating. */
+	virtual cCuboid GetHitBox(void) const = 0;
+
+	/** Returns true if the piece can be rotated CCW the specific number of 90-degree turns. */
+	virtual bool CanRotateCCW(int a_NumRotations) const = 0;
+
+	/** Returns the height, based on m_VerticalStrategy, for this piece when used as the starting piece.
+	If there's no strategy assigned to this piece, returns -1. */
+	int GetStartingPieceHeight(int a_BlockX, int a_BlockZ)
+	{
+		if (m_VerticalStrategy != nullptr)
+		{
+			return m_VerticalStrategy->GetVerticalPlacement(a_BlockX, a_BlockZ);
+		}
+		return -1;
+	}
+
+	void SetVerticalStrategy(cVerticalStrategyPtr a_VerticalStrategy)
+	{
+		m_VerticalStrategy = a_VerticalStrategy;
+	}
+
+	cVerticalStrategyPtr GetVerticalStrategy(void) const
+	{
+		return m_VerticalStrategy;
+	}
+
+	cVerticalLimitPtr GetVerticalLimit(void) const
+	{
+		return m_VerticalLimit;
+	}
+
+	/** Sets the vertical strategy based on the description in the string.
+	If a_LogWarnings is true, logs the parsing problems into the server console.
+	Returns true if successful, false if strategy parsing failed (no strategy assigned). */
+	bool SetVerticalStrategyFromString(const AString & a_StrategyDesc, bool a_LogWarnings);
+
+	/** Sets the vertical limit based on the description string.
+	Returns true if successful, false if limit parsing failed (no limit assigned).
+	If a_LogWarnings is true, any problem is reported into the server console. */
+	bool SetVerticalLimitFromString(const AString & a_LimitDesc, bool a_LogWarnings);
+
+	/** Returns a copy of the a_Pos after rotating the piece the specified number of CCW rotations. */
+	Vector3i RotatePos(const Vector3i & a_Pos, int a_NumCCWRotations) const;
+
+	/** Returns a copy of the connector that is rotated and then moved by the specified amounts. */
+	cConnector RotateMoveConnector(const cConnector & a_Connector, int a_NumCCWRotations, int a_MoveX, int a_MoveY, int a_MoveZ) const;
+
+	/** Returns the hitbox after the specified number of rotations and moved so that a_MyConnector is placed at a_ToConnectorPos. */
+	cCuboid RotateHitBoxToConnector(const cConnector & a_MyConnector, const Vector3i & a_ToConnectorPos, int a_NumCCWRotations) const;
+
+	/** Returns the hitbox after the specified number of CCW rotations and moved by the specified amounts. */
+	cCuboid RotateMoveHitBox(int a_NumCCWRotations, int a_MoveX, int a_MoveY, int a_MoveZ) const;
+};
+
+typedef std::vector<cPiece *> cPieces;
+
+
+
+
+// fwd:
+class cPlacedPiece;
+
+
+
+
+
+/** This class is an interface that stores pieces for a generator.
+Provides lists of pieces based on criteria (IsStarting, HasConnector).
+Provides per-piece weights for random distribution of individual pieces. */
+class cPiecePool
+{
+public:
+	// Force a virtual destructor in all descendants:
+	virtual ~cPiecePool() {}
+
+	/** Returns a list of pieces that contain the specified connector type.
+	The cPiece pointers returned are managed by the pool and the caller doesn't free them. */
+	virtual cPieces GetPiecesWithConnector(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;
+
+	/** Returns the relative weight with which the a_NewPiece is to be selected for placing under a_PlacedPiece through a_ExistingConnector.
+	a_ExistingConnector is the original connector, before any movement or rotation is applied to it.
+	This allows the pool to tweak the piece's chances, based on the previous pieces in the tree and the connector used.
+	The higher the number returned, the higher the chance the piece will be chosen. 0 means the piece will never be chosen. */
+	virtual int GetPieceWeight(
+		const cPlacedPiece & a_PlacedPiece,
+		const cPiece::cConnector & a_ExistingConnector,
+		const cPiece & a_NewPiece
+	)
+	{
+		return 1;
+	}
+
+	/** Returns the relative weight with which the a_NewPiece is to be selected for placing as the first piece.
+	This allows the pool to tweak the piece's chances.
+	The higher the number returned, the higher the chance the piece will be chosen. 0 means the piece will not be chosen.
+	If all pieces return 0, a random piece is chosen, with all equal chances. */
+	virtual int GetStartingPieceWeight(const cPiece & a_NewPiece)
+	{
+		return 1;
+	}
+
+	/** Called after a piece is placed, to notify the pool that it has been used.
+	The pool may adjust the pieces it will return the next time. */
+	virtual void PiecePlaced(const cPiece & a_Piece) = 0;
+
+	/** Called when the pool has finished the current structure and should reset any piece-counters it has
+	for a new structure. */
+	virtual void Reset(void) = 0;
+};
+
+
+
+
+
+/** Represents a single piece that has been placed to specific coords in the world. */
+class cPlacedPiece
+{
+public:
+	cPlacedPiece(const cPlacedPiece * a_Parent, const cPiece & a_Piece, const Vector3i & a_Coords, int a_NumCCWRotations);
+
+	const cPlacedPiece * GetParent           (void) const { return m_Parent; }
+	const cPiece &       GetPiece            (void) const { return *m_Piece; }
+	const Vector3i &     GetCoords           (void) const { return m_Coords; }
+	int                  GetNumCCWRotations  (void) const { return m_NumCCWRotations; }
+	const cCuboid &      GetHitBox           (void) const { return m_HitBox; }
+	int                  GetDepth            (void) const { return m_Depth; }
+	bool                 HasBeenMovedToGround(void) const { return m_HasBeenMovedToGround; }
+
+	/** Returns the coords as a modifiable object. */
+	Vector3i & GetCoords(void) { return m_Coords; }
+
+	/** Returns the connector at the specified index, rotated in the actual placement.
+	Undefined behavior if a_Index is out of range. */
+	cPiece::cConnector GetRotatedConnector(size_t a_Index) const;
+
+	/** Returns a copy of the specified connector, modified to account for the translation and rotation for
+	this placement. */
+	cPiece::cConnector GetRotatedConnector(const cPiece::cConnector & a_Connector) const;
+
+	/** Moves the placed piece Y-wise by the specified offset.
+	Sets m_HasBeenMovedToGround to true, too.
+	Used eg. by village houses. */
+	void MoveToGroundBy(int a_OffsetY);
+
+protected:
+	const cPlacedPiece * m_Parent;
+	const cPiece * m_Piece;
+	Vector3i m_Coords;
+	int m_NumCCWRotations;
+	cCuboid m_HitBox;  // Hitbox of the placed piece, in world coords
+	int m_Depth;       // Depth in the generated piece tree
+
+	/** Set to true once the piece has been moved Y-wise.
+	Used eg. by village houses. */
+	bool m_HasBeenMovedToGround;
+};
+
+typedef std::unique_ptr<cPlacedPiece> cPlacedPiecePtr;
+typedef std::vector<cPlacedPiecePtr> cPlacedPieces;
+
+
+
+
+