Struct SortedMoveAdder 

pub struct SortedMoveAdder<'a> { /* private fields */ }

SortedMoveAdder collects moves including the piece-square score for making the move Moves are sorted by an ‘ordering score’ and stored in a provided SortedMoveHeap

Non-captures are ordered by priotising destination squares that are further up the board relative to the mover, with a bonus for pawns near promotion, a handicap for non-pawn moves to rank 1, and a handicap for pawn moves to low ranks.

Captures are ordered by most-valuable-victim / least-valuable-aggresor with piece scores worth: Pawn: 0 King: 1 (can only be aggresor) Knight: 2 Bishop: 3 Rook: 4 Queen: 5

Move ordering priorities: -250: promotion to bishop -200: promotion to rook -145..-145: capture and promotion to bishop (exact score based on MVV-LVA) -105..-95: capture and promotion to rook (exact score based on MVV-LVA) 0: non-pawn to rank 1 1: - 2: pawn to rank 3 3: pawn to rank 4, non-pawn to rank 2 4: pawn to rank 5, non-pawn to rank 3 5: non-pawn to rank 4 6: non-pawn to rank 5 7: non-pawn to rank 6 8: non-pawn to rank 7 9: non-pawn to rank 8 10: pawn to rank 6 11: pawn to rank 7 20: castle 25: promotion to knight 50: promotion to queen 95..105: capture (exact score based on MVV-LVA) 120..130: capture and promotion to knight (exact score based on MVV-LVA) 145..155: capture and promotion to queen (exact score based on MVV-LVA)

Note: rook and bishop promotions are penalized because queen promotion is nearly always a better choice

Implementations

impl<'a> SortedMoveAdder<'a>

pub fn new( piece_square_table: &'a PieceSquareTable, piece_grid: &'a [Piece; 64], stm: Side, moves: &'a mut SortedMoveHeap, ) -> SortedMoveAdder<'a>

pub fn len(&self) -> usize

pub fn is_empty(&self) -> bool

Trait Implementations

impl<'a> Debug for SortedMoveAdder<'a>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'a> Display for SortedMoveAdder<'a>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'a> MoveAdder for SortedMoveAdder<'a>

fn add_captures(&mut self, from: Square, targets: BB)

fn add_non_captures(&mut self, from: Square, targets: BB)

fn add_castle(&mut self, castle: Castle)

Adds the castle to the move list

fn add_pawn_ep_capture(&mut self, from: Square, to: Square)

Adds pawn en-passant capture to list. From and to are the squares the moving pieces moves from and to, respectively

fn add_pawn_pushes(&mut self, shift: usize, targets: BB)

Adds pawn non-captures to the list. Targets is a bitboard of valid to-squares. Shift is the distance the pawn moved to get to the target square, mod 64. For example, for a white piece moving forward one row this is ‘8’. For a black piece moving forward one row this is 56 (-8 % 64).

fn add_pawn_captures(&mut self, shift: usize, targets: BB)

Adds pawn captures to list. Targets and shift are same as for add_pawn_pushes. Do not use this for en-passant captures (use add_pawn_ep_capture)