build position hashes

kran0 · Jan 26, 2018 · 2b997f3 · 2b997f3
1 parent 176ac14
commit 2b997f3
Show file tree

Hide file tree

Showing 4 changed files with 25 additions and 12 deletions.
diff --git a/modules/game/src/main/BinaryFormat.scala b/modules/game/src/main/BinaryFormat.scala
@@ -45,7 +45,7 @@ object BinaryFormat {
     import scala.collection.JavaConversions.mapAsScalaMap
     def decode(plies: Int, unusedPieces: Option[PieceMap]) = monitor(lila.mon.game.pgn.huffman.decode) {
       HuffmanEncoder.decode(bytes.value, plies) match {
-        case (pgn, pieces, _) => pgn.toVector -> mapAsScalaMap(pieces).toMap
+        case (pgn, pieces, _, _) => pgn.toVector -> mapAsScalaMap(pieces).toMap
       }
     }
     def update(moves: PgnMoves) = HuffmanBinPgn {

diff --git a/modules/game/src/main/java/compression/game/Board.java b/modules/game/src/main/java/compression/game/Board.java
@@ -2,7 +2,7 @@
 
 import java.util.ArrayList;
 
-public final class Board {
+final class Board {
     long pawns;
     long knights;
     long bishops;

diff --git a/modules/game/src/main/java/compression/game/Encoder.java b/modules/game/src/main/java/compression/game/Encoder.java
@@ -8,6 +8,8 @@
 import java.util.regex.Pattern;
 import java.util.regex.Matcher;
 
+import java.nio.ByteBuffer;
+
 import org.lichess.compression.BitReader;
 import org.lichess.compression.BitWriter;
 
@@ -89,14 +91,17 @@ public static byte[] encode(String pgnMoves[]) {
         return writer.toArray();
     }
 
-    public static scala.Tuple3<String[], Map<chess.Pos, chess.Piece>, Set<chess.Pos>> decode(byte input[], int plies) {
+    public static scala.Tuple4<String[], Map<chess.Pos, chess.Piece>, Set<chess.Pos>, byte[]> decode(byte input[], int plies) {
         BitReader reader = new BitReader(input);
 
         String output[] = new String[plies];
 
         Board board = new Board();
         ArrayList<Move> legals = new ArrayList<Move>(80);
 
+        ByteBuffer positionHashBuffer = ByteBuffer.allocate(3 * plies);
+        appendHash(positionHashBuffer, board.zobristHash());
+
         for (int i = 0; i <= plies; i++) {
             board.legalMoves(legals);
 
@@ -109,13 +114,20 @@ public static scala.Tuple3<String[], Map<chess.Pos, chess.Piece>, Set<chess.Pos>
                 Move move = legals.get(Huffman.read(reader));
                 output[i] = san(move, legals);
                 board.play(move);
+
+                if (move.isZeroing()) positionHashBuffer.clear();
+                appendHash(positionHashBuffer, board.zobristHash());
             }
         }
 
-        return new scala.Tuple3<String[], Map<chess.Pos, chess.Piece>, Set<chess.Pos>>(
+        byte positionHashes[] = new byte[positionHashBuffer.remaining()];
+        positionHashBuffer.get(positionHashes);
+
+        return new scala.Tuple4<String[], Map<chess.Pos, chess.Piece>, Set<chess.Pos>, byte[]>(
             output,
             chessPieceMap(board),
-            chessPosSet(board.castlingRights & board.rooks));
+            chessPosSet(board.castlingRights & board.rooks),
+            positionHashes);
     }
 
     private static String san(Move move, ArrayList<Move> legals) {
@@ -170,6 +182,12 @@ private static String san(Move move, ArrayList<Move> legals) {
         return "--";
     }
 
+    private static void appendHash(ByteBuffer buffer, long hash) {
+        buffer.put((byte) (hash & 0xff));
+        buffer.put((byte) ((hash >> 8) & 0xff));
+        buffer.put((byte) ((hash >> 16) & 0xff));
+    }
+
     private static chess.Role chessRole(Role role) {
         switch (role) {
             case PAWN: return chess.Pawn$.MODULE$;

diff --git a/modules/game/src/test/HuffmanPgnTest.scala b/modules/game/src/test/HuffmanPgnTest.scala
@@ -13,7 +13,7 @@ class HuffmanPgnTest extends Specification {
       forall(fixtures) { pgn =>
         val pgnMoves = pgn.split(" ")
         val encoded = GameEncoder.encode(pgnMoves)
-        val (decoded, _, _) = GameEncoder.decode(encoded, pgnMoves.size)
+        val (decoded, _, _, _) = GameEncoder.decode(encoded, pgnMoves.size)
         pgnMoves must_== decoded
       }
     }
@@ -22,15 +22,10 @@ class HuffmanPgnTest extends Specification {
       import scala.collection.JavaConversions.asScalaSet
       val pgnMoves = "d4 h5 c4 Rh6 Nf3 Rh8".split(" ")
       val encoded = GameEncoder.encode(pgnMoves)
-      val (_, _, unmovedRooks) = GameEncoder.decode(encoded, pgnMoves.size)
+      val (_, _, unmovedRooks, _) = GameEncoder.decode(encoded, pgnMoves.size)
       asScalaSet(unmovedRooks) must_== Set(Pos.A1, Pos.H1, Pos.A8)
     }
 
-    "zobrist hashes" in {
-      val board = new Board()
-      board.zobristHash must_== 0x463b96181691fc9cL
-    }
-
     "pass perft test" in {
       // Running the entire suite can take minutes.