Merge pull request #1 from mbluemer/move-generation

Move generation

include/BitBoard.h

@@ -4,6 +4,7 @@
 #include <cstdint>
 #include <string>
 #include <vector>
+#include <string>
 #include "Move.h"
 
 class BitBoard
@@ -32,15 +33,19 @@ class BitBoard
     return r[index];
   }
 
+  static const uint32_t whiteKingSpots = 0x00041041;
+  static const uint32_t blackKingSpots = 0x82000820;
+
+  // Used for determing board from move
+  static const uint32_t topCorner = 0xC3C;
 
   /* Class member variables */
-  const uint32_t m_blackPieces = 0x41C71C3;
-  const uint32_t m_whitePieces = 0xE3820C38;
-  const uint32_t m_kings = 0;
+  uint32_t m_blackPieces = 0x41C71C3;
+  uint32_t m_whitePieces = 0xE3820C38;
+  uint32_t m_kings = 0;
 
   bool m_isBlacksTurn = true;
 
-
   //  static constexpr uint32_t rowMask[8];
   /* Class member functions */
 
@@ -68,8 +73,20 @@ class BitBoard
   int h9() const;
   int h10() const;
 
-
- public:
+  int const getIndex(uint32_t piece);
+
+  void addJumps(std::vector<Move> &moves);
+  void addNormalMoves(std::vector<Move> &moves);
+  void generateAllJumps(BitBoard board, Move move, uint32_t piece, std::vector<Move> &moves);
+  BitBoard boardMove(BitBoard &board, uint32_t piece, uint32_t moveTo);
+  std::vector<uint32_t> generateImmediateJumps(BitBoard &board, uint32_t piece);
+  void addNewMove(uint32_t start, uint32_t end, std::vector<Move> &moves);
+  std::string pieceToString(int piece);
+
+public:
+  BitBoard();
+  BitBoard(uint32_t black, uint32_t white, uint32_t kings);
+
   std::string const player();
   std::vector<Move> const actions();
   BitBoard const result(Move move);

include/Move.h

@@ -2,6 +2,7 @@
 #define MOVE_H
 
 #include <vector>
+#include <cstdint>
 
 class Move
 {
@@ -10,8 +11,13 @@ class Move
 
 public:
 
-    Move() : moves() {};
-    void printMessage();
+    Move();
+    Move(int start);
+    void addMove(int move);
+    void removeLast();
+    bool isEmpty();
+    int length();
+    std::vector<int> getMoves() { return moves; }
 };
 
 #endif

src/BitBoard.cpp

@@ -1,11 +1,16 @@
 #include <cstdint>
 #include <limits.h>
 #include <string>
+#include <vector>
+#include <cmath>
+#include <iostream>
+#include "Move.h"
 #include "BitBoard.h"
 
 /* Private Functions */
 
-
+// These are basic 32 bit rotation functions
+// Details here: http://stackoverflow.com/questions/776508/best-practices-for-circular-shift-rotate-operations-in-c
 uint32_t const BitBoard::rotl32 (uint32_t n, unsigned int c) const
 {
   const unsigned int mask = (CHAR_BIT*sizeof(n)-1);
@@ -22,9 +27,212 @@ uint32_t const BitBoard::rotr32 (uint32_t n, unsigned int c) const
     return (n>>c) | (n<<( (-c)&mask ));
 }
 
+// Given a piece represented by a binary value return it's index
+int const BitBoard::getIndex(uint32_t piece)
+{
+  return (int)std::log2(piece);
+}
+
+void BitBoard::addJumps(std::vector<Move> &moves)
+{
+  uint32_t notOcc = ~(m_whitePieces|m_blackPieces);
+  for (int i = 0; i < 32; ++i) {
+    // grab the specific piece
+    uint32_t piece = (m_isBlacksTurn) ? m_blackPieces & 1<<i : m_whitePieces & 1<<i;
+    if (piece) {
+      generateAllJumps(*this, Move(), piece, moves);
+    }
+  }
+}
+
+void BitBoard::addNormalMoves(std::vector<Move> &moves)
+{
+  uint32_t notOcc = ~(m_whitePieces|m_blackPieces);
+  for (int i = 0; i < 32; ++i) {
+    uint32_t piece;
+    if (m_isBlacksTurn) {
+      piece = m_blackPieces & 1<<i;
+      if (rotl32(piece, 7) & notOcc & upLeft)
+        addNewMove(piece, rotl32(piece, 7), moves);
+      if (rotl32(piece, 1) & notOcc & upRight)
+        addNewMove(piece, rotl32(piece, 1), moves);
+      if (piece & m_kings) {
+        if (rotr32(piece, 7) & notOcc & downRight)
+          addNewMove(piece, rotr32(piece, 7), moves);
+        if (rotr32(piece, 1) & notOcc & downLeft)
+          addNewMove(piece, rotr32(piece, 1), moves);
+      }
+    } else {
+      piece = m_whitePieces & 1<<i;
+      if (rotr32(piece, 7) & notOcc & downRight)
+        addNewMove(piece, rotr32(piece, 7), moves);
+      if (rotr32(piece, 1) & notOcc & downLeft)
+        addNewMove(piece, rotr32(piece, 1), moves);
+      if (piece & m_kings) {
+        if (rotl32(piece, 7) & notOcc & upLeft)
+          addNewMove(piece, rotl32(piece, 7), moves);
+        if (rotl32(piece, 1) & notOcc & upRight)
+          addNewMove(piece, rotl32(piece, 1), moves);
+      }
+    }
+  }
+}
+
+void BitBoard::generateAllJumps(BitBoard board, Move move, uint32_t piece, std::vector<Move> &moves)
+{
+  if (move.isEmpty()) move.addMove(getIndex(piece)); // Add start position
+  std::vector<uint32_t> immediateJumps = generateImmediateJumps(board, piece);
+  if (immediateJumps.size() == 0) {
+    if (move.length() > 1) moves.push_back(move); // If no more jumps add move to list of moves
+  } else {
+    for (uint32_t x : immediateJumps) {
+      move.addMove(getIndex(x));
+      generateAllJumps(boardMove(board, piece, x), move, x, moves);
+      move.removeLast();
+    }
+  }
+}
+
+BitBoard BitBoard::boardMove(BitBoard &board, uint32_t piece, uint32_t moveTo)
+{
+  // Constructor needs black, white, and kings locations so just derive those and instantiate new board object
+  uint32_t white = board.m_whitePieces;
+  uint32_t black = board.m_blackPieces;
+  uint32_t kings = board.m_kings;
+
+  // First figure out if a piece has been take
+  int pieceLoc = getIndex(piece);
+  int moveLoc = getIndex(moveTo);
+  if (piece & topCorner) pieceLoc += 32;
+  if (moveTo & topCorner) moveLoc += 32;
+  int diff = std::abs((double)pieceLoc - moveLoc);
+  int avg = ((pieceLoc + moveLoc) / 2);
+  if (board.m_isBlacksTurn) {
+    if (diff == 2 || diff == 14) {
+      white &= ~(1<<avg); 
+    }
+    black = (black | moveTo) & ~piece;
+    kings = kings | (black & blackKingSpots);
+  } else {
+    if (diff == 2 || diff == 14) black = black & ~(1<<avg);
+    white = (white | moveTo) & ~piece;
+    kings = kings | (white & whiteKingSpots);
+  }
+
+  if (piece & kings) kings = moveTo | (kings & ~piece);
+
+  return BitBoard(black, white, kings);
+}
+
+std::vector<uint32_t> BitBoard::generateImmediateJumps(BitBoard &board, uint32_t piece)
+{
+  std::vector<uint32_t> moves;
+  uint32_t notOcc = ~(board.m_whitePieces|board.m_blackPieces);
+  uint32_t temp;
+  bool isKing = piece & board.m_kings;
+  if (m_isBlacksTurn) {
+    temp = (rotl32(piece, 7) & upLeft) & board.m_whitePieces;
+    if ((rotl32(temp, 7) & upLeft) & notOcc)
+      moves.push_back(rotl32(temp, 7));
+    temp = (rotl32(piece, 1) & upRight) & board.m_whitePieces;
+    if ((rotl32(temp, 1) & upRight) & notOcc)
+      moves.push_back(rotl32(temp, 1));
+    if (isKing) {
+      temp = (rotr32(piece, 7) & downRight) & board.m_whitePieces;
+      if ((rotr32(temp, 7) & downRight) & notOcc)
+        moves.push_back(rotr32(temp, 7));
+      temp = (rotr32(piece, 1) & downLeft) & board.m_whitePieces;
+      if ((rotr32(temp, 1) & downLeft) & notOcc)
+        moves.push_back(rotr32(temp, 1));
+    }
+  } else {
+    temp = (rotr32(piece, 7) & downRight) & board.m_blackPieces;
+    if ((rotr32(temp, 7) & downRight) & notOcc)
+      moves.push_back(rotr32(temp, 7));
+    temp = (rotr32(piece, 1) & downLeft) & board.m_blackPieces;
+    if ((rotr32(temp, 1) & downLeft) & notOcc)
+      moves.push_back(rotr32(temp, 1));
+    if (isKing) {
+      temp = (rotl32(piece, 7) & upLeft) & board.m_blackPieces;
+      if ((rotl32(temp, 7) & upLeft) & notOcc)
+        moves.push_back(rotl32(temp, 7));
+      temp = (rotl32(piece, 1) & upRight) & board.m_blackPieces;
+      if ((rotl32(temp, 1) & upRight) & notOcc)
+        moves.push_back(rotl32(temp, 1));
+    }
+  }
+  return moves;
+}
+
+void BitBoard::addNewMove(uint32_t start, uint32_t end, std::vector<Move> &moves)
+{
+  Move newMove(getIndex(start));
+  newMove.addMove(getIndex(end));
+  moves.push_back(newMove);
+}
+
+std::string BitBoard::pieceToString(int piece)
+{
+  uint32_t pieceLoc = 1<<piece;
+  if (pieceLoc & m_blackPieces)
+    return (pieceLoc & m_kings) ? "B" : "b";
+  if (pieceLoc & m_whitePieces)
+    return (pieceLoc & m_kings) ? "W" : "w";
+  return "-";
+}
+
 /* Public functions */
 
+BitBoard::BitBoard() {};
+
+BitBoard::BitBoard(uint32_t black, uint32_t white, uint32_t kings) :
+  m_blackPieces(black), m_whitePieces(white), m_kings(kings)
+{
+  m_isBlacksTurn = true;
+}
+
 std::string const BitBoard::player()
 {
   return m_isBlacksTurn ? "black" : "white";
 }
+
+std::vector<Move> const BitBoard::actions()
+{
+  std::vector<Move> moves;
+  addJumps(moves);
+  if (moves.empty()) {
+    addNormalMoves(moves);
+  }
+
+  return moves;
+}
+
+BitBoard const BitBoard::result(Move move)
+{
+  BitBoard currBoard = *this;
+  int start{-1};
+  for (int x : move.getMoves()) {
+    if (start == -1) {
+      start = x;
+    } else {
+      currBoard = boardMove(currBoard, 1<<start, 1<<x);
+      start = x;
+    }
+  }
+
+  currBoard.m_isBlacksTurn = !m_isBlacksTurn;
+  return currBoard;
+}
+
+void const BitBoard::printState()
+{
+  std::cout<<"-"<<pieceToString(11)<<"-"<<pieceToString(5)<<"-"<<pieceToString(31)<<"-"<<pieceToString(25)<<std::endl;
+  std::cout<<pieceToString(10)<<"-"<<pieceToString(4)<<"-"<<pieceToString(30)<<"-"<<pieceToString(24)<<"-"<<std::endl;
+  std::cout<<"-"<<pieceToString(3)<<"-"<<pieceToString(29)<<"-"<<pieceToString(23)<<"-"<<pieceToString(17)<<std::endl;
+  std::cout<<pieceToString(2)<<"-"<<pieceToString(28)<<"-"<<pieceToString(22)<<"-"<<pieceToString(16)<<"-"<<std::endl;
+  std::cout<<"-"<<pieceToString(27)<<"-"<<pieceToString(21)<<"-"<<pieceToString(15)<<"-"<<pieceToString(9)<<std::endl;
+  std::cout<<pieceToString(26)<<"-"<<pieceToString(20)<<"-"<<pieceToString(14)<<"-"<<pieceToString(8)<<"-"<<std::endl;
+  std::cout<<"-"<<pieceToString(19)<<"-"<<pieceToString(13)<<"-"<<pieceToString(7)<<"-"<<pieceToString(1)<<std::endl;
+  std::cout<<pieceToString(18)<<"-"<<pieceToString(12)<<"-"<<pieceToString(6)<<"-"<<pieceToString(0)<<"-"<<std::endl;
+}
+

src/Move.cpp

@@ -1,7 +1,28 @@
 #include <iostream>
 #include "Move.h"
 
-void Move::printMessage()
+Move::Move() : moves() {};
+
+Move::Move(int start)
+{
+  moves = {start};
+}
+
+void Move::addMove(int move)
+{
+  moves.push_back(move);
+}
+
+void Move::removeLast()
+{
+  moves.pop_back();
+}
+
+bool Move::isEmpty()
+{
+  return moves.empty();
+}
+ int Move::length()
 {
-  std::cout << "Here is an example message" << std::endl;
+  return moves.size();
 }

src/main.cpp

@@ -1,6 +1,16 @@
 #include <iostream>
+#include <cstdint>
+#include <vector>
+#include "BitBoard.h"
+#include "Move.h"
 
 int main(int argc, const char * argv[]) {
-    std::cout << "Hello world!" << std::endl;
+    BitBoard board(16384, 2097280, 16384);
+    std::vector<Move> moves = board.generateImmediateJumps(16384);
+    for (Move move : moves) {
+      for (int x : move.getMoves()) {
+        std::cout << x << std::endl;
+      }
+    }
     return 0;
 }