Merge branch 'master' into Engine/move-gen

engine/src/bitboard.rs

@@ -5,5 +5,6 @@ mod checkinfo;
 mod attacks;
 mod bitmove;
 mod movebuffer;
+mod movegen;
 
 pub mod board;

engine/src/bitboard/attackmaps.rs

@@ -94,6 +94,64 @@ pub static RAY_TABLE: Lazy<[[u64; 8]; 64]> = Lazy::new(|| {
   return table;
 });
 
+// ROOK_MOVE_MASK[<square_index>]
+pub static ROOK_MOVE_MASK: Lazy<[u64; 64]> = Lazy::new(|| {
+  let mut table = [0u64; 64];
+
+  for sq in 0..64 {
+    for dir in [0, 2, 4, 6] {
+      table[sq] |= RAY_TABLE[sq][dir];
+    }
+  }
+  table
+});
+
+// BISHOP_MOVE_MASK[<square_index>]
+pub static BISHOP_MOVE_MASK: Lazy<[u64; 64]> = Lazy::new(|| {
+  let mut table = [0u64; 64];
+
+  for sq in 0..64 {
+    for dir in [1, 3, 5, 7] {
+      table[sq] |= RAY_TABLE[sq][dir];
+    }
+  }
+  table
+});
+
+// KING_SAFETY_ROOK_MASK[<square_index>]
+pub static KING_SAFETY_ROOK_MASK: Lazy<[u64; 64]> = Lazy::new(|| {
+  let mut table = [0u64; 64];
+
+  for sq in 0..64 {
+    let mut mask = KING_ATTACK_MAP[sq];
+
+    while mask != 0 {
+      let next_sq = mask.trailing_zeros();
+      table[sq] |= ROOK_MOVE_MASK[next_sq as usize];
+      mask &= !(1 << next_sq);
+    }
+  }
+
+  table
+});
+
+// KING_SAFETY_BISHOP_MASK[<square_index>]
+pub static KING_SAFETY_BISHOP_MASK: Lazy<[u64; 64]> = Lazy::new(|| {
+  let mut table = [0u64; 64];
+
+  for sq in 0..64 {
+    let mut mask = KING_ATTACK_MAP[sq];
+
+    while mask != 0 {
+      let next_sq = mask.trailing_zeros();
+      table[sq] |= BISHOP_MOVE_MASK[next_sq as usize];
+      mask &= !(1 << next_sq);
+    }
+  }
+
+  table
+});
+
 
 
 // <----- TESTS ----->

engine/src/bitboard/attacks.rs

@@ -5,6 +5,8 @@ impl Board {
 
   const RANK_2: u64 = 0x0000_0000_0000_FF00;
   const RANK_7: u64 = 0x00FF_0000_0000_0000;
+  const A_FILE: u64 = 0x0101_0101_0101_0101;
+  const H_FILE: u64 = 0x8080_8080_8080_8080;
 
   pub fn get_pseudo_pawn_moves(&self, sq: u32) -> u64 {
     let pawn: u64 = 1 << sq;
@@ -71,6 +73,111 @@ impl Board {
   pub fn get_pseudo_queen_moves(&self, sq: u32) -> u64 {
     return self.get_pseudo_bishop_moves(sq) | self.get_pseudo_rook_moves(sq);
   }
+
+  #[inline]
+  pub fn get_pseudo_bishop_moves_ignore_king(&self, sq: u32) -> u64 {
+    let mut  moves = 0u64;
+    let sq  = sq as usize;
+    let king = self.bitboards[5 + 6*self.side_to_move as usize];
+    let occupancy = self.occupancy[2] & !king;
+    moves |= get_raycast_from_square_in_direction(occupancy, sq, 1);
+    moves |= get_raycast_from_square_in_direction(occupancy, sq, 3);
+    moves |= get_raycast_from_square_in_direction(occupancy, sq, 5);
+    moves |= get_raycast_from_square_in_direction(occupancy, sq, 7);
+
+    return moves;
+  }
+  #[inline]
+  pub fn get_pseudo_rook_moves_ignore_king(&self, sq: u32) -> u64 {
+    let mut moves: u64 = 0u64;
+    let sq = sq as usize;
+    let king = self.bitboards[5 + 6*self.side_to_move as usize];
+    let occupancy = self.occupancy[2] & !king;
+    moves |= get_raycast_from_square_in_direction(occupancy, sq, 0);
+    moves |= get_raycast_from_square_in_direction(occupancy, sq, 2);
+    moves |= get_raycast_from_square_in_direction(occupancy, sq, 4);
+    moves |= get_raycast_from_square_in_direction(occupancy, sq, 6);
+
+    return moves;
+  }
+
+  #[inline]
+  pub fn is_square_attacked(&self, king_sq: u32) -> bool {
+    let offset: usize = 6 * self.side_to_move as usize;
+
+    // rook-queen checks (+)
+    let mut threat_mask: u64 = self.get_pseudo_rook_moves(king_sq);
+    let mut attacker_mask: u64 = self.bitboards[10 - offset] | self.bitboards[9 - offset];
+    if threat_mask & attacker_mask != 0 { return true; }
+
+    // bishop-queen checks (x)
+    threat_mask = self.get_pseudo_bishop_moves(king_sq);
+    attacker_mask = self.bitboards[10 - offset] | self.bitboards[8 - offset];
+    if threat_mask & attacker_mask != 0 { return true; }
+
+    // knight checks (L)
+    threat_mask = KNIGHT_ATTACK_MAP[king_sq as usize];
+    attacker_mask = self.bitboards[7 - offset];
+    if threat_mask & attacker_mask != 0 { return true; }
+
+    // pawn checks (v)
+    threat_mask = PAWN_ATTACK_MAP[king_sq as usize][self.side_to_move as usize];
+    attacker_mask = self.bitboards[6 - offset];
+    return threat_mask & attacker_mask != 0;
+  }
+  pub fn get_safe_king_squares(&self) -> u64 {
+    let offset: usize = 6 * (1 - self.side_to_move as usize);
+    let king_sq = self.bitboards[11 - offset].trailing_zeros() as usize;
+    let bishop_mask = KING_SAFETY_BISHOP_MASK[king_sq];
+    let rook_mask = KING_SAFETY_ROOK_MASK[king_sq];
+    let mut attack_map: u64 = 0u64;
+
+    let mut board: u64 = self.bitboards[offset];
+    if self.side_to_move() == 0 {
+      attack_map |= (board >> 9 & !Self::H_FILE) | (board >> 7 & !Self::A_FILE);
+    }
+    else {
+      attack_map |= (board << 9 & !Self::A_FILE) | (board << 7 & !Self::H_FILE);
+    }
+
+    board = self.bitboards[offset + 1];
+    while board != 0 {
+      let piece_sq: u32 = board.trailing_zeros();
+      board &= !(1 << piece_sq);
+
+      attack_map |= self.get_pseudo_knight_moves(piece_sq);
+    }
+
+    board = self.bitboards[offset + 2] & bishop_mask;
+    while board != 0 {
+      let piece_sq: u32 = board.trailing_zeros();
+      board &= !(1 << piece_sq);
+
+      attack_map |= self.get_pseudo_bishop_moves_ignore_king(piece_sq);
+    }
+
+    board = self.bitboards[offset + 3] & rook_mask;
+    while board != 0 {
+      let piece_sq: u32 = board.trailing_zeros();
+      board &= !(1 << piece_sq);
+
+      attack_map |= self.get_pseudo_rook_moves_ignore_king(piece_sq);
+    }
+
+    board = self.bitboards[offset + 4] & (bishop_mask | rook_mask);
+    while board != 0 {
+      let piece_sq: u32 = board.trailing_zeros();
+      board &= !(1 << piece_sq);
+
+      attack_map |= self.get_pseudo_rook_moves_ignore_king(piece_sq) | self.get_pseudo_bishop_moves_ignore_king(piece_sq);
+    }
+
+    board = self.bitboards[offset + 5];
+    let piece_sq: u32 = board.trailing_zeros();
+    attack_map |= self.get_pseudo_king_moves(piece_sq);
+
+    return !attack_map;
+  }
 }
 
 #[inline(always)]

engine/src/bitboard/legality.rs

@@ -93,6 +93,13 @@ impl Board {
     }
   }
 
+  #[inline]
+  pub(in super) fn get_pin_masked_moves(&self, moves: u64, sq: u32) -> u64 {
+    let sq: usize = sq as usize;
+    if self.pinned_squares[sq] == 4 { return moves; }
+    let dir: u8 = self.pinned_squares[sq];
+    return moves & (RAY_TABLE[sq][dir as usize] | RAY_TABLE[sq][4 + dir as usize]);
+  }
 }
 
 // <----- TESTS ----->

engine/src/bitboard/movegen.rs

@@ -0,0 +1,67 @@
+mod pawns;
+mod knights;
+mod bishops;
+mod rooks;
+mod queens;
+mod kings;
+
+use super::board::Board;
+use super::movebuffer::MoveBuffer;
+use super::bitmove::BitMove;
+use super::checkinfo::CheckInfo;
+use super::utils::*;
+
+impl Board {
+
+  const NO_FILTER: u64 = 0xFFFF_FFFF_FFFF_FFFF;
+
+  pub fn collect_moves(&mut self, buffer: &mut MoveBuffer, temp_buffer: &mut MoveBuffer) -> bool {
+    buffer.clear();
+    self.calc_pinned_squares();
+    let check_info = self.check_test();
+
+    match check_info.check_count {
+      0 => self.collect_all_moves(buffer, temp_buffer),
+      1 => self.collect_moves_single_check(buffer, temp_buffer, &check_info),
+      2 => self.collect_king_evasion(buffer, temp_buffer),
+      _ => panic!("More than 2 checking pieces found as the same time!")
+    }
+    return check_info.check_count > 0;
+  }
+
+  pub(in super) fn collect_all_moves(&self, buffer: &mut MoveBuffer, temp_buffer: &mut MoveBuffer) {
+    let safe_squares = self.get_safe_king_squares();
+
+    self.add_pawn_moves(buffer, temp_buffer, Self::NO_FILTER);
+    self.add_knight_moves(buffer, temp_buffer, Self::NO_FILTER);
+    self.add_bishop_moves(buffer, temp_buffer, Self::NO_FILTER);
+    self.add_rook_moves(buffer, temp_buffer, Self::NO_FILTER);
+    self.add_queen_moves(buffer, temp_buffer, Self::NO_FILTER);
+    self.add_king_moves(buffer, temp_buffer, safe_squares);
+    self.add_king_castles(buffer, safe_squares);
+
+    buffer.append(temp_buffer);
+    temp_buffer.clear();
+  }
+  pub(in super) fn collect_moves_single_check(&self, buffer: &mut MoveBuffer, temp_buffer: &mut MoveBuffer, check_info: &CheckInfo) {
+    let safe_squares = self.get_safe_king_squares();
+
+    self.add_pawn_moves(buffer, temp_buffer, check_info.move_mask);
+    self.add_knight_moves(buffer, temp_buffer, check_info.move_mask);
+    self.add_bishop_moves(buffer, temp_buffer, check_info.move_mask);
+    self.add_rook_moves(buffer, temp_buffer, check_info.move_mask);
+    self.add_queen_moves(buffer, temp_buffer, check_info.move_mask);
+    self.add_king_moves(buffer, temp_buffer, safe_squares);
+
+    buffer.append(temp_buffer);
+    temp_buffer.clear();
+  }
+  pub(in super) fn collect_king_evasion(&self, buffer: &mut MoveBuffer, temp_buffer: &mut MoveBuffer) {
+    let safe_squares = self.get_safe_king_squares();
+
+    self.add_king_moves(buffer, temp_buffer, safe_squares);
+
+    buffer.append(&temp_buffer);
+    temp_buffer.clear();
+  }
+}

engine/src/bitboard/movegen/bishops.rs

@@ -0,0 +1,55 @@
+use super::*;
+
+impl Board {
+
+  pub fn add_bishop_moves(&self, capture_buffer: &mut MoveBuffer, quiet_buffer: &mut MoveBuffer, move_mask: u64) {
+    let piece_index = 2 + self.side_to_move * 6;
+    let mut bishops = self.bitboards[piece_index as usize];
+    let empty = !self.occupancy[2];
+    let opponents = self.occupancy[1 - self.side_to_move as usize];
+    while bishops != 0 {
+      let from_sq = pop_lsb(&mut bishops);
+      let raw_move_map = self.get_pseudo_bishop_moves(from_sq) & move_mask;
+      let move_map = self.get_pin_masked_moves(raw_move_map, from_sq);
+
+      let mut quiet_map = move_map & empty;
+      let mut capture_map = move_map & opponents;
+
+      while quiet_map != 0 {
+        let to_sq = pop_lsb(&mut quiet_map);
+        quiet_buffer.add(BitMove::quiet(
+          from_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+      while capture_map != 0 {
+        let to_sq = pop_lsb(&mut capture_map);
+        capture_buffer.add(BitMove::capture(
+          from_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+    }
+  }
+  pub fn add_bishop_captures(&self, buffer: &mut MoveBuffer, move_mask: u64) {
+    let offset = 6 * self.side_to_move as usize;
+    let mut bishops: u64 = self.bitboards[2 + offset];
+    let opponents = self.occupancy[1 - self.side_to_move as usize];
+    while bishops != 0 {
+      let next_sq: u32 = pop_lsb(&mut bishops);
+      let mut attacks: u64 = self.get_pseudo_bishop_moves(next_sq) & opponents & move_mask;
+      attacks = self.get_pin_masked_moves(attacks, next_sq);
+
+      while attacks != 0 {
+        let to_sq = pop_lsb(&mut attacks);
+        buffer.add(BitMove::capture(
+          next_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+    }
+  }
+}

engine/src/bitboard/movegen/kings.rs

@@ -0,0 +1,88 @@
+use super::*;
+
+impl Board {
+
+  pub fn add_king_moves(&self, capture_buffer: &mut MoveBuffer, quiet_buffer: &mut MoveBuffer, move_mask: u64) {
+    let piece_index = 5 + self.side_to_move * 6;
+    let mut kings = self.bitboards[piece_index as usize];
+    let empty = !self.occupancy[2];
+    let opponents = self.occupancy[1 - self.side_to_move as usize];
+    while kings != 0 {
+      let from_sq = pop_lsb(&mut kings);
+      let move_map = self.get_pseudo_king_moves(from_sq) & move_mask;
+
+      let mut quiet_map = move_map & empty;
+      let mut capture_map = move_map & opponents;
+
+      while quiet_map != 0 {
+        let to_sq = pop_lsb(&mut quiet_map);
+        quiet_buffer.add(BitMove::quiet(
+          from_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+      while capture_map != 0 {
+        let to_sq = pop_lsb(&mut capture_map);
+        capture_buffer.add(BitMove::capture(
+          from_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+    }
+  }
+  pub fn add_king_captures(&self, buffer: &mut MoveBuffer, move_mask: u64) {
+    let offset = 6 * self.side_to_move as usize;
+    let mut kings: u64 = self.bitboards[5 + offset];
+    let opponents = self.occupancy[1 - self.side_to_move as usize];
+    while kings != 0 {
+      let next_sq: u32 = pop_lsb(&mut kings);
+      let mut attacks: u64 = self.get_pseudo_king_moves(next_sq) & opponents & move_mask;
+      attacks = self.get_pin_masked_moves(attacks, next_sq);
+
+      while attacks != 0 {
+        let to_sq = pop_lsb(&mut attacks);
+        buffer.add(BitMove::capture(
+          next_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+    }
+  }
+  pub fn add_king_castles(&self, buffer: &mut MoveBuffer, move_mask: u64) {
+    if self.castling_rights & (0b11 << (2 - 2 * self.side_to_move)) == 0 {
+      return;
+    }
+    
+    let offset = 5 + 6 * self.side_to_move as u8;
+    let castle_offset = 2 - 2 * self.side_to_move as u8;
+    let castling_rights = self.castling_rights & 3 << castle_offset;
+    let occupied = self.occupancy[2];
+    let king_sq = self.bitboards[offset as usize].trailing_zeros();
+      
+    let queenside_mask = 0b111 << (king_sq - 3);
+    let kingside_mask = 0b11 << (king_sq + 1);
+
+    if (castling_rights & 1 << castle_offset) != 0
+        && queenside_mask & occupied == 0
+        && !move_mask & 0b11 << (king_sq - 2) == 0
+        && !self.is_square_attacked(king_sq - 2) {
+      buffer.add(BitMove::castle(
+        king_sq as u8,
+        (king_sq - 2) as u8
+      ));
+    }
+    if (castling_rights & 2 << castle_offset) != 0
+        && kingside_mask & occupied == 0
+        && !move_mask & 0b11 << (king_sq + 1) == 0
+        && !self.is_square_attacked(king_sq + 2) {
+      buffer.add(BitMove::castle(
+        king_sq as u8,
+        (king_sq + 2) as u8
+      ));
+    }
+    
+  }
+}

engine/src/bitboard/movegen/knights.rs

@@ -0,0 +1,55 @@
+use super::*;
+
+impl Board {
+
+  pub fn add_knight_moves(&self, capture_buffer: &mut MoveBuffer, quiet_buffer: &mut MoveBuffer, move_mask: u64) {
+    let piece_index = 1 + self.side_to_move * 6;
+    let mut knights = self.bitboards[piece_index as usize];
+    let empty = !self.occupancy[2];
+    let opponents = self.occupancy[1 - self.side_to_move as usize];
+    while knights != 0 {
+      let from_sq = pop_lsb(&mut knights);
+      let raw_move_map = self.get_pseudo_knight_moves(from_sq) & move_mask;
+      let move_map = self.get_pin_masked_moves(raw_move_map, from_sq);
+
+      let mut quiet_map = move_map & empty;
+      let mut capture_map = move_map & opponents;
+
+      while quiet_map != 0 {
+        let to_sq = pop_lsb(&mut quiet_map);
+        quiet_buffer.add(BitMove::quiet(
+          from_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+      while capture_map != 0 {
+        let to_sq = pop_lsb(&mut capture_map);
+        capture_buffer.add(BitMove::capture(
+          from_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+    }
+  }
+  pub fn add_knight_captures(&self, buffer: &mut MoveBuffer, move_mask: u64) {
+    let offset = 6 * self.side_to_move as usize;
+    let mut knights: u64 = self.bitboards[1 + offset];
+    let opponents = self.occupancy[1 - self.side_to_move as usize];
+    while knights != 0 {
+      let next_sq: u32 = pop_lsb(&mut knights);
+      let mut attacks: u64 = self.get_pseudo_knight_moves(next_sq) & opponents & move_mask;
+      attacks = self.get_pin_masked_moves(attacks, next_sq);
+
+      while attacks != 0 {
+        let to_sq = pop_lsb(&mut attacks);
+        buffer.add(BitMove::capture(
+          next_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+    }
+  }
+}

engine/src/bitboard/movegen/pawns.rs

@@ -0,0 +1,76 @@
+use super::*;
+
+impl Board {
+
+  pub fn add_pawn_quiets(&self, buffer: &mut MoveBuffer, move_mask: u64) {
+    let offset: u8 = self.side_to_move * 6;
+    let mut pawns: u64 = self.bitboards[offset as usize];
+    while pawns != 0 {
+      let next_sq = pop_lsb(&mut pawns);
+
+      let mut quiets: u64 = self.get_pseudo_pawn_moves(next_sq) & move_mask;
+      quiets = self.get_pin_masked_moves(quiets, next_sq);
+      while quiets != 0 {
+        let to_sq = quiets.trailing_zeros();
+
+        if (self.side_to_move == 0 && quiets.trailing_zeros() / 8 == 7)
+        || (self.side_to_move == 1 && quiets.trailing_zeros() / 8 == 0) {
+          for piece_type in [4, 3, 2, 1] {
+            buffer.add(BitMove::quiet(
+              next_sq as u8,
+              to_sq as u8,
+              Some(piece_type)
+            ));
+          }
+        }
+        else {
+          buffer.add(BitMove::quiet(
+            next_sq as u8,
+            to_sq as u8,
+            None
+          ));
+        }
+        quiets &= !(1 << to_sq);
+      }
+    }
+  }
+  pub fn add_pawn_captures(&self, buffer: &mut MoveBuffer, move_mask: u64) {
+    let offset = 6 * self.side_to_move as usize;
+    let mut pawns: u64 = self.bitboards[offset];
+    let opponents = self.occupancy[1 - self.side_to_move as usize];
+    while pawns != 0 {
+      let next_sq = pop_lsb(&mut pawns);
+
+      let mut attacks: u64 = self.get_pseudo_pawn_captures(next_sq) & move_mask;
+      attacks = self.get_pin_masked_moves(attacks, next_sq);
+      attacks &= opponents;
+
+      while attacks != 0 {
+        let to_sq = attacks.trailing_zeros();
+
+        if (self.side_to_move == 0 && attacks.trailing_zeros() / 8 == 7)
+        || (self.side_to_move == 1 && attacks.trailing_zeros() / 8 == 0) {
+          for piece_type in [4, 3, 2, 1] {
+            buffer.add(BitMove::capture(
+              next_sq as u8,
+              to_sq as u8,
+              Some(piece_type)
+            ));
+          }
+        }
+        else {
+          buffer.add(BitMove::capture(
+            next_sq as u8,
+            to_sq as u8,
+            None
+          ));
+        }
+        attacks &= !(1 << to_sq);
+      }
+    }
+  }
+  pub fn add_pawn_moves(&self, capture_buffer: &mut MoveBuffer, quiet_buffer: &mut MoveBuffer, move_mask: u64) {
+    self.add_pawn_captures(capture_buffer, move_mask);
+    self.add_pawn_quiets(quiet_buffer, move_mask);
+  }
+}

engine/src/bitboard/movegen/queens.rs

@@ -0,0 +1,55 @@
+use super::*;
+
+impl Board {
+
+  pub fn add_queen_moves(&self, capture_buffer: &mut MoveBuffer, quiet_buffer: &mut MoveBuffer, move_mask: u64) {
+    let piece_index = 4 + self.side_to_move * 6;
+    let mut queens = self.bitboards[piece_index as usize];
+    let empty = !self.occupancy[2];
+    let opponents = self.occupancy[1 - self.side_to_move as usize];
+    while queens != 0 {
+      let from_sq = pop_lsb(&mut queens);
+      let raw_move_map = self.get_pseudo_queen_moves(from_sq) & move_mask;
+      let move_map = self.get_pin_masked_moves(raw_move_map, from_sq);
+
+      let mut quiet_map = move_map & empty;
+      let mut capture_map = move_map & opponents;
+
+      while quiet_map != 0 {
+        let to_sq = pop_lsb(&mut quiet_map);
+        quiet_buffer.add(BitMove::quiet(
+          from_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+      while capture_map != 0 {
+        let to_sq = pop_lsb(&mut capture_map);
+        capture_buffer.add(BitMove::capture(
+          from_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+    }
+  }
+  pub fn add_queen_captures(&self, buffer: &mut MoveBuffer, move_mask: u64) {
+    let offset = 6 * self.side_to_move as usize;
+    let mut queens: u64 = self.bitboards[4 + offset];
+    let opponents = self.occupancy[1 - self.side_to_move as usize];
+    while queens != 0 {
+      let next_sq: u32 = pop_lsb(&mut queens);
+      let mut attacks: u64 = self.get_pseudo_queen_moves(next_sq) & opponents & move_mask;
+      attacks = self.get_pin_masked_moves(attacks, next_sq);
+
+      while attacks != 0 {
+        let to_sq = pop_lsb(&mut attacks);
+        buffer.add(BitMove::capture(
+          next_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+    }
+  }
+}

engine/src/bitboard/movegen/rooks.rs

@@ -0,0 +1,55 @@
+use super::*;
+
+impl Board {
+
+  pub fn add_rook_moves(&self, capture_buffer: &mut MoveBuffer, quiet_buffer: &mut MoveBuffer, move_mask: u64) {
+    let piece_index = 3 + self.side_to_move * 6;
+    let mut rooks = self.bitboards[piece_index as usize];
+    let empty = !self.occupancy[2];
+    let opponents = self.occupancy[1 - self.side_to_move as usize];
+    while rooks != 0 {
+      let from_sq = pop_lsb(&mut rooks);
+      let raw_move_map = self.get_pseudo_rook_moves(from_sq) & move_mask;
+      let move_map = self.get_pin_masked_moves(raw_move_map, from_sq);
+
+      let mut quiet_map = move_map & empty;
+      let mut capture_map = move_map & opponents;
+
+      while quiet_map != 0 {
+        let to_sq = pop_lsb(&mut quiet_map);
+        quiet_buffer.add(BitMove::quiet(
+          from_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+      while capture_map != 0 {
+        let to_sq = pop_lsb(&mut capture_map);
+        capture_buffer.add(BitMove::capture(
+          from_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+    }
+  }
+  pub fn add_rook_captures(&self, buffer: &mut MoveBuffer, move_mask: u64) {
+    let offset = 6 * self.side_to_move as usize;
+    let mut rooks: u64 = self.bitboards[3 + offset];
+    let opponents = self.occupancy[1 - self.side_to_move as usize];
+    while rooks != 0 {
+      let next_sq: u32 = pop_lsb(&mut rooks);
+      let mut attacks: u64 = self.get_pseudo_rook_moves(next_sq) & opponents & move_mask;
+      attacks = self.get_pin_masked_moves(attacks, next_sq);
+
+      while attacks != 0 {
+        let to_sq = pop_lsb(&mut attacks);
+        buffer.add(BitMove::capture(
+          next_sq as u8,
+          to_sq as u8,
+          None
+        ));
+      }
+    }
+  }
+}

engine/src/bitboard/utils.rs

@@ -1,13 +1,13 @@
 #[inline(always)]
-pub fn pop_lsb(value: &mut u64) -> usize {
-  let idx = value.trailing_zeros() as usize;
+pub fn pop_lsb(value: &mut u64) -> u32 {
+  let idx = value.trailing_zeros();
   *value &= !(1 << idx);
   return idx;
 }
 
 #[inline(always)]
-pub fn pop_msb(value: &mut u64) -> usize {
-  let idx = 63 - value.leading_zeros() as usize;
+pub fn pop_msb(value: &mut u64) -> u32 {
+  let idx = 63 - value.leading_zeros();
   *value &= !(1 << idx);
   return idx;
 }
@@ -72,7 +72,7 @@ mod tests {
       0xBEAC_DBE0_903A_AC00,
       0x01E8_C895_A6F0_0000
     ];
-    let expected_values: [usize; 6] = [63, 0, 4, 2, 10, 20];
+    let expected_values: [u32; 6] = [63, 0, 4, 2, 10, 20];
 
     // tests
     for index in 0..6 {
@@ -92,7 +92,7 @@ mod tests {
       0x0000_C1C3_201C_0DB1,
       0x0000_0203_0DE4_E944
     ];
-    let expected_values: [usize; 6] = [63, 0, 61, 57, 47, 41];
+    let expected_values: [u32; 6] = [63, 0, 61, 57, 47, 41];
 
     // tests
     for index in 0..6 {