Subversion Repositories Games.Chess Giants

#if defined(SYZYGY)

#  include "tbprobe.h"

#endif

  ROOT_MOVE rtemp;

  if (swindle_mode) {

      tb_result =

          tb_probe_root(Occupied(white), Occupied(black),

          Kings(white) | Kings(black), Queens(white) | Queens(black),

          Rooks(white) | Rooks(black), Bishops(white) | Bishops(black),

          Knights(white) | Knights(black), Pawns(white) | Pawns(black),

          Reversible(1), 0, EnPassant(1), wtm, NULL);

            (tb_root == TB_CURSED_WIN))

      }

    }

          tb_result =

              tb_probe_root(Occupied(white), Occupied(black),

              Kings(white) | Kings(black), Queens(white) | Queens(black),

              Rooks(white) | Rooks(black), Bishops(white) | Bishops(black),

              Knights(white) | Knights(black), Pawns(white) | Pawns(black),

            tb_result = 4 - TB_GET_WDL(tb_result);

            if (tb_result < tb_root)

          }

  do {

    done = 1;

    for (mvp = 0; mvp < n_root_moves - 1; mvp++) {

      if (root_moves[mvp].path.pathv < root_moves[mvp + 1].path.pathv) {

        rtemp = root_moves[mvp];

        root_moves[mvp] = root_moves[mvp + 1];

        root_moves[mvp + 1] = rtemp;

        done = 0;

      }

    }

}

/* last modified 07/11/16 */

/*

 *******************************************************************************

 *                                                                             *

 *   RootMoveEGTB() is used to handle the case where we are using syzygy end-  *

 *   game tablebases and the root position is found in them.  We need to use   *

 *   the DTZ tables to play the best move we can find since the game outcome   *

 *   is known for each possible move at this point.  We return it in a manner  *

 *   similar to Book().                                                        *

 *                                                                             *

 *   Note:  This depends on RootMoveList() being called FIRST since it is the  *

 *   responsible party to note that we are drawn at the root according to EGTB *

 *   and if appropriate, it will let RootMoveEGTB() know this to activate      *

 *   "swindle mode" and play on with a search rather than an instant move.     *

 *                                                                             *

 *******************************************************************************

 */

int RootMoveEGTB(int wtm) {

#if defined(SYZYGY)

  TREE *const tree = block[0];

  int tb_result, result;

/*

 ************************************************************

 *                                                          *

 *  first, we need to find the best TB move.  Simply, this  *

 *  is the move that gives us the best result, even though  *

 *  it might be speculative in the case of choosing a       *

 *  "cursed win" which is still technically a draw if the   *

 *  opponent makes no errors.                               *

 *                                                          *

 ************************************************************

 */

  EGTB_use = EGTBlimit;

  if (EGTB_use <= 0)

    return 0;

  if (EGTB_draw && !puzzling && swindle_mode)

    EGTB_use = 0;

  if (EGTBlimit && !EGTB_use)

    Print(32, "Drawn at root, trying for swindle.\n");

  if (EGTB_use && TotalAllPieces <= EGTBlimit && !Castle(0, white) &&

      !Castle(0, black)) {

    tree->egtb_probes++;

    tb_result =

        tb_probe_root(Occupied(white), Occupied(black),

        Kings(white) | Kings(black), Queens(white) | Queens(black),

        Rooks(white) | Rooks(black), Bishops(white) | Bishops(black),

        Knights(white) | Knights(black), Pawns(white) | Pawns(black),

        Reversible(1), 0, EnPassant(1), wtm, NULL);

    if (tb_result != TB_RESULT_FAILED) {

      int value, piece, captured;

      unsigned cmove, omove;

      if (n_root_moves > 0) {

        tree->egtb_hits++;

        result = TB_GET_WDL(tb_result);

        switch (result) {

          case TB_LOSS:

            value = -TBWIN;

            break;

          case TB_WIN:

            value = TBWIN;

            break;

          case TB_BLESSED_LOSS:

            value = -3;

            break;

          case TB_DRAW:

            value = 0;

            break;

          case TB_CURSED_WIN:

            value = 3;

            break;

          default:

            value = TB_GET_DTZ(tb_result);;

            break;

        }

        if (result != TB_LOSS && result != TB_WIN) {

          if (MaterialSTM(wtm) > 0)

            value += 1;

          else if (MaterialSTM(wtm) < 0)

            value -= 1;

        }

        piece = abs(PcOnSq(TB_GET_FROM(tb_result)));

        captured = abs(PcOnSq(TB_GET_TO(tb_result)));

        cmove =

            TB_GET_FROM(tb_result) | (TB_GET_TO(tb_result) << 6) | (piece <<

            12) | (captured << 15);

        if (TB_GET_PROMOTES(tb_result))

          cmove |= (6 - TB_GET_PROMOTES(tb_result)) << 18;

        end_time = ReadClock();

        tree->pv[0].path[1] = cmove;

        tree->pv[0].pathl = 2;

        tree->pv[0].pathh = 4;

        tree->pv[0].pathd = 0;

        tree->pv[0].pathv = value;

        MakeMove(tree, 1, wtm, cmove);

        result = Mated(tree, 2, Flip(wtm));

        UnmakeMove(tree, 1, wtm, cmove);

        if (result == 1)

          tree->pv[0].pathv = MATE - 2;

        else if (result == 2)

          tree->pv[0].pathv = DrawScore(wtm);

/*

 ************************************************************

 *                                                          *

 *  If we are not mated and did not mate on the move, we    *

 *  flip the side on move and find the best TB move so that *

 *  we can show the expected reply in the PV.               *

 *                                                          *

 ************************************************************

 */

        else {

          MakeMove(tree, 1, wtm, cmove);

          tree->egtb_probes++;

          tb_result =

              tb_probe_root(Occupied(white), Occupied(black),

              Kings(white) | Kings(black), Queens(white) | Queens(black),

              Rooks(white) | Rooks(black), Bishops(white) | Bishops(black),

              Knights(white) | Knights(black), Pawns(white) | Pawns(black),

              Reversible(2), 0, EnPassant(2), Flip(wtm), NULL);

          if (tb_result != TB_RESULT_FAILED) {

            tree->egtb_hits++;

            piece = abs(PcOnSq(TB_GET_FROM(tb_result)));

            captured = abs(PcOnSq(TB_GET_TO(tb_result)));

            omove =

                TB_GET_FROM(tb_result) | (TB_GET_TO(tb_result) << 6) | (piece

                << 12) | (captured << 15);

            if (TB_GET_PROMOTES(tb_result))

              omove |= (6 - TB_GET_PROMOTES(tb_result)) << 18;

            end_time = ReadClock();

            tree->pv[0].path[2] = omove;

            tree->pv[0].pathl = 3;

          }

          UnmakeMove(tree, 1, wtm, cmove);

        }

      }

/*

 ************************************************************

 *                                                          *

 *  We now know the best move to play, and possibly the     *

 *  opponent's best response.  Display this info and then   *

 *  we wait for the next move to pop in.                    *

 *                                                          *

 ************************************************************

 */

      Print(2, "        depth     time       score   variation\n");

      if (n_root_moves == 0) {

        program_end_time = ReadClock();

        tree->pv[0].pathl = 0;

        tree->pv[0].pathd = 0;

        if (Check(wtm))

          value = -(MATE - 1);

        else

          value = DrawScore(wtm);

        Print(2, "                             Mated   (no moves)\n");

        tree->nodes_searched = 1;

        if (!puzzling)

          last_root_value = value;

        return 1;

      }

      DisplayPV(tree, 5, wtm, end_time - start_time, &tree->pv[0], 1);

      return 1;

    }

  }

#endif

  return 0;