// PieceGenerator.h
// Declares the cBFSPieceGenerator class and cDFSPieceGenerator class
// representing base classes for generating structures composed of individual "pieces"
/*
Each uses a slightly different approach to generating:
- DFS extends pieces one by one until it hits the configured depth (or can't connect another piece anymore),
then starts looking at adjacent connectors (like depth-first search).
- BFS keeps a pool of currently-open connectors, chooses one at random and tries to place a piece on it,
thus possibly extending the pool of open connectors (like breadth-first search).
*/
#pragma once
#include "../Defines.h"
#include "../Cuboid.h"
#include "../Noise.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
{
/** Position relative to the piece */
Vector3i m_Pos;
/** Type of the connector. Any arbitrary number; the generator connects only connectors of the same type. */
int m_Type;
/** Direction in which the connector is facing.
Will be matched by the opposite direction for the connecting connector. */
eBlockFace m_Direction;
cConnector(int a_X, int a_Y, int a_Z, int a_Type, eBlockFace a_Direction);
cConnector(const Vector3i & a_Pos, int a_Type, eBlockFace a_Direction);
};
typedef std::vector<cConnector> cConnectors;
/** 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 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;
/** This class is an interface that provides pieces for the generator. It can keep track of what pieces were
placed and adjust the returned piece vectors. */
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;
/** 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 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; }
protected:
const cPlacedPiece * m_Parent;
const cPiece * m_Piece;
Vector3i m_Coords;
int m_NumCCWRotations;
cCuboid m_HitBox;
int m_Depth;
};
typedef std::vector<cPlacedPiece *> cPlacedPieces;
class cPieceGenerator
{
public:
cPieceGenerator(cPiecePool & a_PiecePool, int a_Seed);
/** Cleans up all the memory used by the placed pieces.
Call this utility function instead of freeing the items on your own. */
static void FreePieces(cPlacedPieces & a_PlacedPieces);
protected:
/** The type used for storing a connection from one piece to another, while building the piece tree. */
struct cConnection
{
cPiece * m_Piece; // The piece being connected
cPiece::cConnector m_Connector; // The piece's connector being used (relative non-rotated coords)
int m_NumCCWRotations; // Number of rotations necessary to match the two connectors
cConnection(cPiece & a_Piece, cPiece::cConnector & a_Connector, int a_NumCCWRotations);
};
typedef std::vector<cConnection> cConnections;
/** The type used for storing a pool of connectors that will be attempted to expand by another piece. */
struct cFreeConnector
{
cPlacedPiece * m_Piece;
cPiece::cConnector m_Connector;
cFreeConnector(cPlacedPiece * a_Piece, const cPiece::cConnector & a_Connector);
};
typedef std::vector<cFreeConnector> cFreeConnectors;
cPiecePool & m_PiecePool;
cNoise m_Noise;
int m_Seed;
/** Selects a starting piece and places it, including the rotations.
Also puts the piece's connectors in a_OutConnectors. */
cPlacedPiece * PlaceStartingPiece(int a_BlockX, int a_BlockY, int a_BlockZ, cFreeConnectors & a_OutConnectors);
/** Tries to place a new piece at the specified (placed) connector. Returns true if successful. */
bool TryPlacePieceAtConnector(
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
);
/** 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
a_ToPos is the world-coords position on which the new connector should be placed (1 block away from a_ExistingConnector, in its Direction)
a_NewConnector is in the original (non-rotated) coords.
Returns true if the piece fits, false if not. */
bool CheckConnection(
const cPiece::cConnector & a_ExistingConnector, // The existing connector
const Vector3i & a_ToPos, // The position on which the new connector should be placed
const cPiece & a_Piece, // The new piece
const cPiece::cConnector & a_NewConnector, // The connector of the new piece
int a_NumCCWRotations, // Number of rotations for the new piece to align the connector
const cPlacedPieces & a_OutPieces // All the already-placed pieces to check
);
/** DEBUG: Outputs all the connectors in the pool into stdout.
a_NumProcessed signals the number of connectors from the pool that should be considered processed (not listed). */
void DebugConnectorPool(const cPieceGenerator::cFreeConnectors & a_ConnectorPool, size_t a_NumProcessed);
} ;
class cBFSPieceGenerator :
public cPieceGenerator
{
typedef cPieceGenerator super;
public:
cBFSPieceGenerator(cPiecePool & a_PiecePool, int a_Seed);
/** Generates a placement for pieces at the specified coords.
Caller must free each individual cPlacedPiece in a_OutPieces. */
void PlacePieces(int a_BlockX, int a_BlockY, int a_BlockZ, int a_MaxDepth, cPlacedPieces & a_OutPieces);
};
class cDFSPieceGenerator :
public cPieceGenerator
{
public:
cDFSPieceGenerator(cPiecePool & a_PiecePool, int a_Seed);
/** Generates a placement for pieces at the specified coords.
Caller must free each individual cPlacedPiece in a_OutPieces. */
void PlacePieces(int a_BlockX, int a_BlockY, int a_BlockZ, cPlacedPieces & a_OutPieces);
};
