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evaluate.cpp
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evaluate.cpp
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#include "evaluate.h"
#include "uci.h"
#include "bitboards.h"
#include "board.h"
#include "macros.h"
extern unsigned char passed_pawn_value[8];
extern unsigned char passed_pawn_late_value[8];
extern unsigned char canidate_pp_value[8];
extern unsigned char canidate_pp_late_value[8];
extern unsigned char pp_self_blocking_penalty[8];
extern unsigned char pp_unthreatened_path_bonus[8];
extern unsigned char pp_clear_path_bonus[8];
extern unsigned char BISHOP_PAIR_BONUS[17];
using namespace std;
PAWNTABLE pawntable;
int contempt(CHESSBOARD * b) {
//return DRAW;
if(b->getMaterialValue(b->getActivePlayer()) >= b->getMaterialValue(!b->getActivePlayer()))
return -50;
return DRAW;
}
bool insufficientMaterial(CHESSBOARD *b) {
// FIDE draws:
// both sides have a bare king
// one side has a king and a minor piece against a bare king
// one side has two knights against the bare king
// Todo:
// both sides have a king and a bishop, the bishops being the same color
// White bare king:
if (b->getMaterialValue(WHITE) == KING_VALUE) {
switch (b->getMaterialValue(BLACK)) {
// Two bare kings
case KING_VALUE:
return true;
break;
// Single minor piece:
case KING_VALUE + BISHOP_VALUE:
return true;
break;
//Two Knights:
case KING_VALUE + KNIGHT_VALUE + KNIGHT_VALUE:
if (!b->getPieceBB(BLACK, nBishop)) return true;
break;
}
}
// Black bare king:
if (b->getMaterialValue(BLACK) == KING_VALUE) {
switch (b->getMaterialValue(WHITE)) {
// Single minor piece:
case KING_VALUE + BISHOP_VALUE:
return true;
break;
//Two Knights:
case KING_VALUE + KNIGHT_VALUE + KNIGHT_VALUE:
if (!b->getPieceBB(WHITE, nBishop)) return true;
break;
}
}
return false;
}
int materialScore(CHESSBOARD * b) {
//Only used for debugging!
int score =
bitcount(b->getPieceBB(WHITE,nPawn)) * nPieceValue[nPawn]
+ bitcount(b->getPieceBB(WHITE,nKnight)) * nPieceValue[nKnight]
+ bitcount(b->getPieceBB(WHITE,nBishop)) * nPieceValue[nBishop]
+ bitcount(b->getPieceBB(WHITE,nRook)) * nPieceValue[nRook]
+ bitcount(b->getPieceBB(WHITE,nQueen)) * nPieceValue[nQueen]
+ bitcount(b->getPieceBB(WHITE,nKing)) * nPieceValue[nKing]
- bitcount(b->getPieceBB(BLACK,nPawn)) * nPieceValue[nPawn]
- bitcount(b->getPieceBB(BLACK,nKnight)) * nPieceValue[nKnight]
- bitcount(b->getPieceBB(BLACK,nBishop)) * nPieceValue[nBishop]
- bitcount(b->getPieceBB(BLACK,nRook)) * nPieceValue[nRook]
- bitcount(b->getPieceBB(BLACK,nQueen)) * nPieceValue[nQueen]
- bitcount(b->getPieceBB(BLACK,nKing)) * nPieceValue[nKing];
return score;
}
void DevelopementEval() {
/* Taken from: http://chessprogramming.wikispaces.com/file/view/LittleChessEvaluationCompendium.pdf/388410128/LittleChessEvaluationCompendium.pdf
Order of development
+20 for developing n before b
-30 for developing q before 2 minor pieces are developed
-50 for developing r before 2 minors are developed
+60 for castling to developing pieces on the other side
+50 for castling short to castling long if both possible
-35 for playing twice with the same piece in the opening
Repeated moves in the opening
Repeated moves with the same piece or pawn in the opening (up till move 6 or 7) are usually
bad, they are a waste of time and stand in the way of development.
-20cps for a repeated move with a piece
-10cps for a repeated move with a pawn
*/
}
short PawnEval::Shelter(CHESSBOARD * b, unsigned char square) {
return 0;
}
void PawnEval::Opening(CHESSBOARD *b, short &opening_bonus, short &endgame_bonus, PAWNSTRUCTURE & pawn_structure) {
// This score is from the POV of white.
// That way we dont have to double count positions in the pawn hash table
// TODO: -isolated (on open/closed files)
// -backward (open/closed)
// -candidate passed pawn
// -unstoppable pawn bonus = queen - pawn (only in king/pawn endings?)
//Keep local versions of score changes, so the hashing will be accurate:
short pawn_opening_score = 0;
short pawn_endgame_score = 0;
#ifdef ENABLE_PAWN_HASH
//Check the pawn hash table:
if (pawntable.getScores(b->getPawnKey(), pawn_opening_score, pawn_endgame_score, pawn_structure)) {
opening_bonus += pawn_opening_score;
endgame_bonus += pawn_endgame_score;
return;
}
#endif
pawn_structure.short_shelter_penalty[WHITE] = 0; //[2] = { 0, 0 };
pawn_structure.short_shelter_penalty[BLACK] = 0; //[2] = { 0, 0 };
pawn_structure.long_shelter_penalty[WHITE] = 0; //[2] = { 0, 0 };
pawn_structure.long_shelter_penalty[BLACK] = 0; //[2] = { 0, 0 };
pawn_structure.passed_pawns[WHITE] = 0;
pawn_structure.passed_pawns[BLACK] = 0;
//There is no hash hit, so continue with the evaluation:
bitboard pieceDB = b->getPieceBB(WHITE, nPawn);
//Before turning bits off in the pieceDB, first adjust shelter score to prevent back row mates:
if ( (pieceDB & mask::short_castle_pawns[WHITE]) == mask::short_castle_pawns[WHITE])
pawn_structure.short_shelter_penalty[WHITE] = shelter_penalty[RankOf(a3) - 1];
if ( (pieceDB & mask::long_castle_pawns[WHITE]) == mask::long_castle_pawns[WHITE])
pawn_structure.long_shelter_penalty[WHITE] = shelter_penalty[RankOf(h3) - 1];
if ( (pieceDB & mask::mid_castle_pawns[WHITE]) == mask::mid_castle_pawns[WHITE])
pawn_structure.mid_shelter_penalty[WHITE] = shelter_penalty[RankOf(e4) - 1];
while (pieceDB) {
int square = bitscan_msb(pieceDB);
bool open_file = !(b->getPieceBB(BLACK, nPawn) & mask::north[square]);
/***********************************
Piece Values:
***********************************/
//Square value:
pawn_opening_score += nSquareValue[WHITE][nPawn][square];
pawn_endgame_score += nEndgamePawnValue[WHITE][square];
// Edge pawn penalty:
if ((((bitboard)1) << square) & (FileMask(a) | FileMask(h)))
pawn_opening_score += -EDGE_PAWN_PENALTY;
/***********************************
Passed/Canidates:
***********************************/
if (!(b->getPieceBB(BLACK, nPawn) & mask::passed_pawn[WHITE][square])) {
pawn_structure.passed_pawns[WHITE] |= ((unsigned char)1 << FileOf(square));
pawn_opening_score += passed_pawn_value[RankOf(square) - 1];
pawn_endgame_score += passed_pawn_late_value[RankOf(square) - 1];
}
// Canidate:
else if (open_file) {
//caution: double use of the isolated pawn mask here.
bitboard enemies = mask::isolated_pawn[square] & b->getPieceBB(BLACK, nPawn);
bitboard friends = mask::isolated_pawn[square] & b->getPieceBB(WHITE, nPawn);
if (bitcount(friends) >= bitcount(enemies)) {
pawn_opening_score += canidate_pp_value[RankOf(square) - 1];
pawn_endgame_score += canidate_pp_late_value[RankOf(square) - 1];
}
}
/*********************************************
Strength (how connected):
*********************************************/
//Pawn Duo
if ((b->getPieceBB(WHITE, nPawn)&~FileMask(a))&(((bitboard)1) << (square - 1))) {//check the pawn to the right.
pawn_opening_score += PAWN_DUO_EARLY_VALUE;
pawn_endgame_score += PAWN_DUO_LATE_VALUE;
}
//Connected (supported by another pawn)
else if (b->getPieceBB(WHITE, nPawn)&mask::pawn_captures[BLACK][square]) {//check the pawns one rank below
pawn_opening_score += CONNECTED_PAWN_EARLY_VALUE;
pawn_endgame_score += CONNECTED_PAWN_LATE_VALUE;
}
/*********************************************
Weakness (Isolated/backward):
*********************************************/
else {
//Isolated pawn penalty:
if (!(b->getPieceBB(WHITE, nPawn) & mask::isolated_pawn[square])) {
pawn_opening_score += -ISOLATED_PAWN_EARLY_PENALTY;
pawn_endgame_score += -ISOLATED_PAWN_LATE_PENALTY;
if (open_file) {
pawn_opening_score += -ISOLATED_OPEN_FILE;
}
}
//Backwards pawn penalty:
else {
unsigned char closest_friend = bitscan_lsb(mask::isolated_pawn[square] & b->getPieceBB(WHITE, nPawn));
bool backwards = false;
// Is this the furthest back pawn out of the adjacent files?
if (RankOf(square) < RankOf(closest_friend)) {
backwards = true;
//is the closest friend 1 move away?
if (RankOf(square + 8) >= RankOf(closest_friend)) {
//is there something stopping us from getting there?
bitboard enemy_control = b->getPieceBB(BLACK, nPawn)
| ((b->getPieceBB(BLACK, nPawn) & ~FileMask(h)) >> 9)
| ((b->getPieceBB(BLACK, nPawn) & ~FileMask(a)) >> 7);
if (!(enemy_control & (((bitboard)1) << (square + 8)))) backwards = false;
}
//at spawn, is the friend 2 moves away?
else if ((RankOf(square) == 2) && (RankOf(square + 16) >= RankOf(closest_friend))) {
//is there something stopping us from getting there?
bitboard enemy_control = b->getPieceBB(BLACK, nPawn)
| ((b->getPieceBB(BLACK, nPawn) & ~FileMask(h)) >> 9)
| ((b->getPieceBB(BLACK, nPawn) & ~FileMask(a)) >> 7);
if (!(enemy_control & ((((bitboard)1) << (square + 8)) | (((bitboard)1) << (square + 16))))) backwards = false;
}
}
if (backwards) {
pawn_opening_score += -BACKWARD_PAWN_EARLY_PENALTY;
pawn_endgame_score += -BACKWARD_PAWN_LATE_PENALTY;
if (open_file)
pawn_opening_score += -BACKWARD_PAWN_OPEN_FILE;
}
}
}
/*********************************************
Doubled:
*********************************************/
//Doubled pawn penalty:
if (b->getPieceBB(WHITE, nPawn) & mask::south[square]) {
//look behind the pawn for another pawn.
pawn_opening_score += -DOUBLED_PAWN_EARLY_PENALTY;
pawn_endgame_score += -DOUBLED_PAWN_LATE_PENALTY;
if (open_file) {
pawn_opening_score += -DOUBLED_PAWN_OPEN_FILE;
pawn_endgame_score += -DOUBLED_PAWN_OPEN_FILE;
}
if (RankOf( bitscan_msb(b->getPieceBB(WHITE, nPawn)&mask::south[square]) ) > 2){
pawn_opening_score += -DOUBLED_PAWN_REAR_ADVANCED;
pawn_endgame_score += -DOUBLED_PAWN_REAR_ADVANCED;
}
}
/*********************************************
Shelter:
*********************************************/
else {
// if it isnt doubled, then it is the least advanced pawn on that file,
// so we need to consider it for king shelter scoring.
if (FileOf(square) >= 5) { //long
pawn_structure.short_shelter_penalty[WHITE] += shelter_penalty[RankOf(square) - 1];
pawn_structure.short_shelter_penalty[BLACK] += storm_penalty[RankOf(square) - 1];
}
else if (FileOf(square) <= 2) { //short
pawn_structure.long_shelter_penalty[WHITE] += shelter_penalty[RankOf(square) - 1];
pawn_structure.long_shelter_penalty[BLACK] += storm_penalty[RankOf(square) - 1];
}
else { //middle
pawn_structure.mid_shelter_penalty[WHITE] += shelter_penalty[RankOf(square) - 1];
pawn_structure.mid_shelter_penalty[BLACK] += storm_penalty[RankOf(square) - 1];
}
}
//Turn off the bit:
pieceDB ^= (((bitboard)1) << square);
//cout << index_to_alg(square) << ": " << pawn_opening_score << "/" << pawn_endgame_score << endl;
}
pieceDB = b->getPieceBB(BLACK, nPawn);
//Before turning bits off in the pieceDB, first adjust shelter score to prevent back row mates:
if ( (pieceDB & mask::short_castle_pawns[BLACK]) == mask::short_castle_pawns[BLACK])
pawn_structure.short_shelter_penalty[BLACK] = shelter_penalty[9 - RankOf(a6) - 1];
if ( (pieceDB & mask::long_castle_pawns[BLACK]) == mask::long_castle_pawns[BLACK])
pawn_structure.long_shelter_penalty[BLACK] = shelter_penalty[9 - RankOf(h6) - 1];
if ( (pieceDB & mask::mid_castle_pawns[BLACK]) == mask::mid_castle_pawns[BLACK])
pawn_structure.mid_shelter_penalty[BLACK] = shelter_penalty[9 - RankOf(e5) - 1];
while (pieceDB) {
int square = bitscan_msb(pieceDB);
bool open_file = !(b->getPieceBB(WHITE, nPawn) & mask::south[square]);
/*********************************************
Piece Values:
*********************************************/
//Square value:
pawn_opening_score -= nSquareValue[BLACK][nPawn][square];
pawn_endgame_score -= nEndgamePawnValue[BLACK][square];
//Edge pawn penalty
if ((((bitboard)1) << square) & (FileMask(a) | FileMask(h)))
pawn_opening_score -= -EDGE_PAWN_PENALTY;
/*********************************************
Passed/Canidates:
*********************************************/
//Passed pawn bonus:
if (!(b->getPieceBB(WHITE, nPawn) & mask::passed_pawn[BLACK][square])) {
pawn_structure.passed_pawns[BLACK] |= ((unsigned char)1 << FileOf(square));
pawn_opening_score -= passed_pawn_value[9 - RankOf(square) - 1];
pawn_endgame_score -= passed_pawn_late_value[9 - RankOf(square) - 1];
}
// Canidate:
else if (open_file) {
//double use of the isolated pawn mask here.
bitboard enemies = mask::isolated_pawn[square] & b->getPieceBB(WHITE, nPawn);
bitboard friends = mask::isolated_pawn[square] & b->getPieceBB(BLACK, nPawn);
if (bitcount(friends) >= bitcount(enemies)) {
pawn_opening_score -= canidate_pp_value[ 9 - RankOf(square) - 1];
pawn_endgame_score -= canidate_pp_late_value[ 9 - RankOf(square) - 1];
}
}
/*********************************************
Strength (how connected):
*********************************************/
//Pawn Duo
if ((b->getPieceBB(BLACK, nPawn)&~FileMask(h))&(((bitboard)1) << (square + 1))) {//check the pawn to the left.
pawn_opening_score -= PAWN_DUO_EARLY_VALUE;
pawn_endgame_score -= PAWN_DUO_LATE_VALUE;
}
//Connected (supported by another pawn)
else if (b->getPieceBB(BLACK, nPawn)&mask::pawn_captures[WHITE][square]) { //check the pawns one rank below
pawn_opening_score -= CONNECTED_PAWN_EARLY_VALUE;
pawn_endgame_score -= CONNECTED_PAWN_LATE_VALUE;
}
/*********************************************
Weakness (Isolated/backward):
*********************************************/
else {
//Isolated pawn penalty:
if (!(b->getPieceBB(BLACK, nPawn) & mask::isolated_pawn[square])) {
pawn_opening_score -= -ISOLATED_PAWN_EARLY_PENALTY;
pawn_endgame_score -= -ISOLATED_PAWN_LATE_PENALTY;
if (open_file) {
pawn_opening_score -= -ISOLATED_OPEN_FILE;
}
}
//Backwards pawn penalty:
else {
unsigned char closest_friend = bitscan_msb(mask::isolated_pawn[square] & b->getPieceBB(BLACK, nPawn));
bool backwards = false;
// Is this the furthest back pawn out of the adjacent files?
if (RankOf(square) > RankOf(closest_friend)) {
backwards = true;
//is the closest friend 1 move away?
if (RankOf(square - 8) <= RankOf(closest_friend)) {
//is there something stopping us from getting there?
bitboard enemy_control = b->getPieceBB(WHITE, nPawn)
| ((b->getPieceBB(WHITE, nPawn) & ~FileMask(a)) << 9)
| ((b->getPieceBB(WHITE, nPawn) & ~FileMask(h)) << 7);
if (!(enemy_control & (((bitboard)1) << (square - 8)))) backwards = false;
}
//at spawn, is the friend 2 moves away?
else if ((RankOf(square) == 7) && (RankOf(square - 16) <= RankOf(closest_friend))) {
//is there something stopping us from getting there?
bitboard enemy_control = b->getPieceBB(WHITE, nPawn)
| ((b->getPieceBB(WHITE, nPawn) & ~FileMask(a)) << 9)
| ((b->getPieceBB(WHITE, nPawn) & ~FileMask(h)) << 7);
if (!(enemy_control & ((((bitboard)1) << (square - 8)) | (((bitboard)1) << (square - 16))))) backwards = false;
}
}
if (backwards) {
pawn_opening_score -= -BACKWARD_PAWN_EARLY_PENALTY;
pawn_endgame_score -= -BACKWARD_PAWN_LATE_PENALTY;
if (open_file)
pawn_opening_score -= -BACKWARD_PAWN_OPEN_FILE;
}
}
}
/*********************************************
Doubled:
*********************************************/
//Doubled pawn penalty:
if (b->getPieceBB(BLACK, nPawn) & mask::north[square]) {
pawn_opening_score -= -DOUBLED_PAWN_EARLY_PENALTY;
pawn_endgame_score -= -DOUBLED_PAWN_LATE_PENALTY;
if (open_file) {
pawn_opening_score -= -DOUBLED_PAWN_OPEN_FILE;
pawn_endgame_score -= -DOUBLED_PAWN_OPEN_FILE;
}
if (RankOf(bitscan_lsb(b->getPieceBB(BLACK, nPawn)&mask::north[square])) < 7){
pawn_opening_score -= -DOUBLED_PAWN_REAR_ADVANCED;
pawn_endgame_score -= -DOUBLED_PAWN_REAR_ADVANCED;
}
}
/*********************************************
Shelter:
*********************************************/
else {
// if it isnt doubled, then it is the least advanced pawn on that file,
// so we need to consider it for king shelter scoring.
if (FileOf(square) >= 5) { //long
pawn_structure.short_shelter_penalty[BLACK] += shelter_penalty[9 - RankOf(square) - 1];
pawn_structure.short_shelter_penalty[WHITE] += storm_penalty[9 - RankOf(square) - 1];
}
else if (FileOf(square) <= 2) { //short
pawn_structure.long_shelter_penalty[BLACK] += shelter_penalty[9 - RankOf(square) - 1];
pawn_structure.long_shelter_penalty[WHITE] += storm_penalty[9 - RankOf(square) - 1];
}
else { //middle
pawn_structure.mid_shelter_penalty[BLACK] += shelter_penalty[9 - RankOf(square) - 1];
pawn_structure.mid_shelter_penalty[WHITE] += storm_penalty[9 - RankOf(square) - 1];
}
}
//Turn off the bit:
pieceDB ^= (((bitboard)1) << square);
//cout << index_to_alg(square) << ": " << pawn_opening_score << "/" << pawn_endgame_score << endl;
}
#ifdef ENABLE_PAWN_HASH
pawntable.saveScore(b->getPawnKey(), pawn_opening_score, pawn_endgame_score, pawn_structure);
#endif
/*
//DEBUG:
if(b->getPawnKey() != b->generatePawnKey()) {
cout << "EVAL: PAWN KEYS DONT MATCH " << endl;
cout << "Pawn BBs:" << endl;
bitprint(b->getPieceBB(WHITE,nPawn));
bitprint(b->getPieceBB(BLACK,nPawn));
system("PAUSE");
}
*/
//Return values:
opening_bonus += pawn_opening_score;
endgame_bonus += pawn_endgame_score;
}
void evaluateMaterialTable(MaterialTable * m, short &opening_score, short &endgame_score) {
//Bishop Pair Bonuses:
if (m->bishops[WHITE] > 1) {
opening_score += BISHOP_PAIR_EARLY_BONUS; //BISHOP_PAIR_BONUS[m->pawns[WHITE] + m->pawns[BLACK]];
endgame_score += BISHOP_PAIR_LATE_BONUS; //BISHOP_PAIR_BONUS[m->pawns[WHITE] + m->pawns[BLACK]];
}
if (m->bishops[BLACK] > 1) {
opening_score -= BISHOP_PAIR_EARLY_BONUS; //BISHOP_PAIR_BONUS[m->pawns[WHITE] + m->pawns[BLACK]];
endgame_score -= BISHOP_PAIR_LATE_BONUS; //BISHOP_PAIR_BONUS[m->pawns[WHITE] + m->pawns[BLACK]];
}
}
int evaluate(CHESSBOARD * b, bool side_to_move) {
//Returns game evaluation with respect to the player to move.
//Phase and flags:
//short gauge = phase_gauge(b);
short phase = 0;
bool end_game[2] = { false, false };
//bool no_pieces[2] = { true, true }; //will turn this off if pieces are found later in the eval.
short endgame_score = 0;
short opening_score = 0;
MaterialTable material;
//Side to move (tempo) bonus:
if (side_to_move == WHITE) {
opening_score += SIDE_TO_MOVE_EARLY_BONUS;
endgame_score += SIDE_TO_MOVE_LATE_BONUS;
}
else {
opening_score -= SIDE_TO_MOVE_EARLY_BONUS;
endgame_score -= SIDE_TO_MOVE_LATE_BONUS;
}
unsigned char square;
bitboard attacks[2] = { 0, 0 };
short king_attackers[2] = { 0, 0 };
short attackers_weight[2] = { 0, 0 };
/*******************************************************************************
Pawn Structure Evaluation (not including dynamic, situation specific things):
*******************************************************************************/
PAWNSTRUCTURE pawn_structure;
PawnEval::Opening(b, opening_score, endgame_score, pawn_structure);
material.pawns[WHITE] = bitcount(b->getPieceBB(WHITE, nPawn));
material.pawns[BLACK] = bitcount(b->getPieceBB(BLACK, nPawn));
phase += (material.pawns[WHITE] + material.pawns[BLACK])*PAWN_PHASE_VALUE;
/*******************************************************************************
Kings:
*******************************************************************************/
bitboard king_circle[2];
square = bitscan_msb(b->getPieceBB(WHITE, nKing));
opening_score += nSquareValue[WHITE][nKing][square];
endgame_score += nEndgameKingValue[WHITE][square];
king_circle[WHITE] = mask::king_moves[square];
attacks[WHITE] = king_circle[WHITE];
// King safety, Pawn Shelter, Pawn Storm:
if (!end_game[WHITE]) {
//Short Side:
if ((((bitboard)1) << square) & mask::short_castle_area[WHITE]) {
opening_score += -pawn_structure.short_shelter_penalty[WHITE];
}
//Long Side:
else if ((((bitboard)1) << square) & mask::long_castle_area[WHITE]) {
opening_score += -pawn_structure.long_shelter_penalty[WHITE];
}
//Middle Area:
else {
short penalty = pawn_structure.mid_shelter_penalty[WHITE];
if (b->getCastlingRights(WHITE, KING_SIDE))
penalty = pawn_structure.short_shelter_penalty[WHITE];
if (b->getCastlingRights(WHITE, QUEEN_SIDE) && (pawn_structure.long_shelter_penalty < pawn_structure.short_shelter_penalty))
penalty = pawn_structure.long_shelter_penalty[WHITE];
opening_score += -((pawn_structure.mid_shelter_penalty[WHITE] + penalty) / 2);
}
}
square = bitscan_msb(b->getPieceBB(BLACK, nKing));
opening_score -= nSquareValue[BLACK][nKing][square];
endgame_score -= nEndgameKingValue[BLACK][square];
king_circle[BLACK] = mask::king_moves[square];
attacks[BLACK] = king_circle[BLACK];
if (!end_game[BLACK]) {
//Short Side:
if ((((bitboard)1) << square) & mask::short_castle_area[BLACK]) {
opening_score -= -pawn_structure.short_shelter_penalty[BLACK];
}
//Long Side:
else if ((((bitboard)1) << square) & mask::long_castle_area[BLACK]) {
opening_score -= -pawn_structure.long_shelter_penalty[BLACK];
}
//Middle Area:
else {
short penalty = pawn_structure.mid_shelter_penalty[BLACK];
if (b->getCastlingRights(BLACK, KING_SIDE))
penalty = pawn_structure.short_shelter_penalty[BLACK];
if (b->getCastlingRights(BLACK, QUEEN_SIDE) && (pawn_structure.long_shelter_penalty > pawn_structure.short_shelter_penalty))
penalty = pawn_structure.long_shelter_penalty[BLACK];
opening_score -= -((pawn_structure.mid_shelter_penalty[BLACK] + penalty) / 2);
}
}
/*******************************************************************************
Knights:
*******************************************************************************/
bitboard pieceDB = b->getPieceBB(WHITE, nKnight);
bitboard mobility;
while (pieceDB) {
phase += KNIGHT_PHASE_VALUE;
material.knights[WHITE]++;
//no_pieces[WHITE] = false;
square = bitscan_msb(pieceDB);
opening_score += nSquareValue[WHITE][nKnight][square];
endgame_score += nSquareValue[WHITE][nKnight][square];
// Mobility:
mobility = mask::knight_moves[square];
attacks[WHITE] |= (mobility & ~b->getOccupiedBB(WHITE));
opening_score += knight_mobility[bitcount(mobility)];
endgame_score += knight_mobility[bitcount(mobility)];
// King Threats:
if (mobility&king_circle[BLACK]) {
king_attackers[WHITE]++;
attackers_weight[WHITE] += KNIGHT_THREAT_WEIGHT;
}
//Reduce value in late game:
endgame_score += -KNIGHT_LATE_PENALTY;
pieceDB ^= (((bitboard)1) << square);
}
pieceDB = b->getPieceBB(BLACK, nKnight);
while (pieceDB) {
phase += KNIGHT_PHASE_VALUE;
material.knights[BLACK]++;
//no_pieces[BLACK] = false;
square = bitscan_msb(pieceDB);
opening_score -= nSquareValue[BLACK][nKnight][square];
endgame_score -= nSquareValue[BLACK][nKnight][square];
// Mobility:
mobility = mask::knight_moves[square];
attacks[BLACK] |= (mobility & ~b->getOccupiedBB(BLACK));
opening_score -= knight_mobility[bitcount(mobility)];
endgame_score -= knight_mobility[bitcount(mobility)];
// King Threats:
if (mobility&king_circle[WHITE]) {
king_attackers[BLACK]++;
attackers_weight[BLACK] += KNIGHT_THREAT_WEIGHT;
}
//Reduce value in late game:
endgame_score -= -KNIGHT_LATE_PENALTY;
pieceDB ^= (((bitboard)1) << square);
}
/*******************************************************************************
Bishops:
*******************************************************************************/
// TODO: -consider xray
// -Penalize "bad" bishops.
pieceDB = b->getPieceBB(WHITE, nBishop);
//Trapped Bishop Pattern check:
#ifdef ENABLE_PATTERNS
if (((pieceDB >> 7)&(b->getPieceBB(BLACK, nPawn))&(mask::trapped_bishop_long[WHITE])) ||
((pieceDB >> 9)&(b->getPieceBB(BLACK, nPawn))&(mask::trapped_bishop_short[WHITE])) ){
opening_score += -TRAPPED_BISHOP;
endgame_score += -TRAPPED_BISHOP;
}
#endif
while (pieceDB) {
phase += BISHOP_PHASE_VALUE;
material.bishops[WHITE]++;
//no_pieces[WHITE] = false;
square = bitscan_msb(pieceDB);
opening_score += nSquareValue[WHITE][nBishop][square];
endgame_score += nSquareValue[WHITE][nBishop][square];
//Mobility:
mobility = (mask::MagicBishopMoves[square][((b->getOccupiedBB(BOTH)&mask::MagicBishopMask[square]) * mask::MagicBishopNumbers[square]) >> mask::MagicBishopShift[square]] & ~b->getOccupiedBB(WHITE));
attacks[WHITE] |= mobility;
opening_score += bishop_mobility[bitcount(mobility)];
endgame_score += bishop_mobility[bitcount(mobility)];
// King Threats:
if (mobility&king_circle[BLACK]) {
king_attackers[WHITE]++;
attackers_weight[WHITE] += BISHOP_THREAT_WEIGHT;
}
pieceDB ^= (((bitboard)1) << square);
}
pieceDB = b->getPieceBB(BLACK, nBishop);
//Trapped Bishop Pattern check:
#ifdef ENABLE_PATTERNS
if (((pieceDB << 7)&(b->getPieceBB(WHITE, nPawn))&(mask::trapped_bishop_long[BLACK])) ||
((pieceDB << 9)&(b->getPieceBB(WHITE, nPawn))&(mask::trapped_bishop_short[BLACK]))){
opening_score -= -TRAPPED_BISHOP;
endgame_score -= -TRAPPED_BISHOP;
}
#endif
while (pieceDB) {
phase += BISHOP_PHASE_VALUE;
material.bishops[BLACK]++;
//no_pieces[BLACK] = false;
square = bitscan_msb(pieceDB);
opening_score -= nSquareValue[BLACK][nBishop][square];
endgame_score -= nSquareValue[BLACK][nBishop][square];
//Mobility:
mobility = (mask::MagicBishopMoves[square][((b->getOccupiedBB(BOTH)&mask::MagicBishopMask[square]) * mask::MagicBishopNumbers[square]) >> mask::MagicBishopShift[square]] & ~b->getOccupiedBB(BLACK));
attacks[BLACK] |= mobility;
opening_score -= bishop_mobility[bitcount(mobility)];
endgame_score -= bishop_mobility[bitcount(mobility)];
// King Threats:
if (mobility&king_circle[WHITE]) {
king_attackers[BLACK]++;
attackers_weight[BLACK] += BISHOP_THREAT_WEIGHT;
}
pieceDB ^= (((bitboard)1) << square);
}
/*******************************************************************************
Rooks:
*******************************************************************************/
// TODO: -make an open file bonus that is a function of number of pawns.
// -bonus for rooks not moving until a castle in early game.
// -seventh rank bonus
// -supporting passed pawns bonus
pieceDB = b->getPieceBB(WHITE, nRook);
while (pieceDB) {
square = bitscan_msb(pieceDB);
phase += ROOK_PHASE_VALUE;
material.rooks[WHITE]++;
//Adjust value:
opening_score += ROOK_ADJUSTMENT[material.total_pawns()];
endgame_score += ROOK_ADJUSTMENT[material.total_pawns()];
// Mobility:
mobility = (mask::MagicRookMoves[square][((b->getOccupiedBB(BOTH) & mask::MagicRookMask[square]) * mask::MagicRookNumbers[square]) >> mask::MagicRookShift[square]] & ~b->getOccupiedBB(WHITE));
attacks[WHITE] |= mobility;
opening_score += rook_mobility[bitcount(mobility)];
endgame_score += rook_mobility[bitcount(mobility)];
//Trapped Rook Pattern:
#ifdef ENABLE_PATTERNS
if (RankOf(square) == 1) {
if (FileOf(square) < 2) {
if (b->getPieceBB(WHITE, nKing)&mask::trapped_rook_short_king[WHITE])
opening_score += -TRAPPED_BISHOP; }
else if (FileOf(square) > 5) {
if (b->getPieceBB(WHITE, nKing)&mask::trapped_rook_long_king[WHITE])
opening_score += -TRAPPED_BISHOP; }
}
#endif
// King Threats:
if (mobility&king_circle[BLACK]) {
king_attackers[WHITE]++;
attackers_weight[WHITE] += ROOK_THREAT_WEIGHT;
}
// 7th rank bonus
if (RankOf(square) == 7) {
opening_score += ROOK_7TH_FILE_EARLY_BONUS;
endgame_score += ROOK_7TH_FILE_LATE_BONUS;
}
//opening_score -= ROOK_OPEN_FILE_EARLY_BONUS / 2;
//endgame_score -= ROOK_OPEN_FILE_LATE_BONUS / 2;
// Semi-Open file bonus:
if ((mask::north[square] & (b->getPieceBB(WHITE, nPawn))) == 0) {
opening_score += ROOK_SEMI_OPEN_FILE_EARLY_BONUS;
endgame_score += ROOK_SEMI_OPEN_FILE_LATE_BONUS;
// King Threats for semi open files:
/*
if (mobility&king_circle[BLACK]) {
opening_score += SEMIOPEN_THREAT_EARLY_BONUS; // * ( (mobility&king_circle[BLACK])? 1 : 0 );
endgame_score += SEMIOPEN_THREAT_LATE_BONUS; // * ( (mobility&king_circle[BLACK])? 1 : 0 );
}
*/
// Full-Open file bonus
if ((mask::north[square] & (b->getPieceBB(BLACK, nPawn))) == 0) {
opening_score += ROOK_OPEN_FILE_EARLY_BONUS - ROOK_SEMI_OPEN_FILE_EARLY_BONUS;
endgame_score += ROOK_OPEN_FILE_LATE_BONUS - ROOK_SEMI_OPEN_FILE_LATE_BONUS;
// King Threats for fully open files:
/*
if (mobility&king_circle[BLACK]) {
opening_score += OPEN_THREAT_EARLY_BONUS; // * ( (mobility&king_circle[BLACK])? 1 : 0 );
endgame_score += OPEN_THREAT_LATE_BONUS; // * ( (mobility&king_circle[BLACK])? 1 : 0 );
}
*/
}
}
pieceDB ^= (((bitboard)1) << square);
}
pieceDB = b->getPieceBB(BLACK, nRook);
while (pieceDB) {
square = bitscan_msb(pieceDB);
phase += ROOK_PHASE_VALUE;
material.rooks[BLACK]++;
//Adjust value:
opening_score -= ROOK_ADJUSTMENT[material.total_pawns()];
endgame_score -= ROOK_ADJUSTMENT[material.total_pawns()];
// Mobility:
mobility = (mask::MagicRookMoves[square][((b->getOccupiedBB(BOTH) & mask::MagicRookMask[square]) * mask::MagicRookNumbers[square]) >> mask::MagicRookShift[square]] & ~b->getOccupiedBB(BLACK) );
attacks[BLACK] |= mobility;
opening_score -= rook_mobility[bitcount(mobility)];
endgame_score -= rook_mobility[bitcount(mobility)];
//Trapped Rook Pattern:
#ifdef ENABLE_PATTERNS
if (RankOf(square) == 8) {
if (FileOf(square) > 2) {
if (b->getPieceBB(BLACK, nKing)&mask::trapped_rook_short_king[BLACK])
opening_score -= -TRAPPED_BISHOP; }
else if (FileOf(square) < 5) {
if (b->getPieceBB(BLACK, nKing)&mask::trapped_rook_long_king[BLACK])
opening_score -= -TRAPPED_BISHOP; }
}
#endif
// King Threats:
if (mobility&king_circle[WHITE]) {
king_attackers[BLACK]++;
attackers_weight[BLACK] += ROOK_THREAT_WEIGHT;
}
// 7th rank bonus
if (RankOf(square) == 2) {
opening_score -= ROOK_7TH_FILE_EARLY_BONUS;
endgame_score -= ROOK_7TH_FILE_LATE_BONUS;
}
//opening_score += ROOK_OPEN_FILE_EARLY_BONUS / 2;
//endgame_score += ROOK_OPEN_FILE_LATE_BONUS / 2;
// Semi-Open file bonus:
if ((mask::south[square] & (b->getPieceBB(BLACK, nPawn))) == 0) {
opening_score -= ROOK_SEMI_OPEN_FILE_EARLY_BONUS;
endgame_score -= ROOK_SEMI_OPEN_FILE_LATE_BONUS;
// King Threats for semi open files:
/*
if (mobility&king_circle[WHITE]) {
opening_score -= SEMIOPEN_THREAT_EARLY_BONUS;// * ( (mobility&king_circle[WHITE])? 1 : 0 );
endgame_score -= SEMIOPEN_THREAT_LATE_BONUS;// * ( (mobility&king_circle[WHITE])? 1 : 0 );
}
*/
// Full-Open file bonus
if ((mask::south[square] & (b->getPieceBB(WHITE, nPawn))) == 0) {
opening_score -= ROOK_OPEN_FILE_EARLY_BONUS;
endgame_score -= ROOK_OPEN_FILE_LATE_BONUS;
// King Threats for fully open files:
/*
if (mobility&king_circle[WHITE]) {
opening_score -= OPEN_THREAT_EARLY_BONUS * ((mobility&king_circle[WHITE]) ? 1 : 0);
endgame_score -= OPEN_THREAT_LATE_BONUS * ((mobility&king_circle[WHITE]) ? 1 : 0);
}
*/
}
}
pieceDB ^= (((bitboard)1) << square);
}
/*******************************************************************************
Queens:
*******************************************************************************/
// TODO: -penalty for activating the queen early.
pieceDB = b->getPieceBB(WHITE, nQueen);
while (pieceDB) {
phase += QUEEN_PHASE_VALUE;
material.queens[WHITE]++;
square = bitscan_msb(pieceDB);
#ifdef ENABLE_QUEEN_PST
opening_score += nSquareValue[WHITE][nQueen][square];
endgame_score += nSquareValue[WHITE][nQueen][square];
#endif
// Diagonal Mobility:
mobility = (mask::MagicRookMoves[square][((b->getOccupiedBB(BOTH) & mask::MagicRookMask[square]) * mask::MagicRookNumbers[square]) >> mask::MagicRookShift[square]] & ~b->getOccupiedBB(WHITE) );
mobility |= (mask::MagicBishopMoves[square][((b->getOccupiedBB(BOTH)&mask::MagicBishopMask[square]) * mask::MagicBishopNumbers[square]) >> mask::MagicBishopShift[square]] & ~b->getOccupiedBB(WHITE));
attacks[WHITE] |= mobility;
opening_score += queen_mobility[bitcount(mobility)];
endgame_score += queen_mobility[bitcount(mobility)];
if (mobility&king_circle[BLACK]) {
king_attackers[WHITE]++;
attackers_weight[WHITE] += QUEEN_THREAT_WEIGHT;
}
pieceDB ^= (((bitboard)1) << square);
}
pieceDB = b->getPieceBB(BLACK, nQueen);
while (pieceDB) {
phase += QUEEN_PHASE_VALUE;
material.queens[BLACK]++;
square = bitscan_msb(pieceDB);
#ifdef ENABLE_QUEEN_PST
opening_score -= nSquareValue[BLACK][nQueen][square];
endgame_score -= nSquareValue[BLACK][nQueen][square];
#endif
// Diagonal Mobility:
mobility = ( mask::MagicRookMoves[square][((b->getOccupiedBB(BOTH) & mask::MagicRookMask[square]) * mask::MagicRookNumbers[square]) >> mask::MagicRookShift[square]] & ~b->getOccupiedBB(BLACK));
mobility |= (mask::MagicBishopMoves[square][((b->getOccupiedBB(BOTH)&mask::MagicBishopMask[square]) * mask::MagicBishopNumbers[square]) >> mask::MagicBishopShift[square]] & ~b->getOccupiedBB(BLACK));
attacks[BLACK] |= mobility;
opening_score -= queen_mobility[bitcount(mobility)];
endgame_score -= queen_mobility[bitcount(mobility)];
if (mobility&king_circle[WHITE]) {
king_attackers[BLACK]++;
attackers_weight[BLACK] += QUEEN_THREAT_WEIGHT;
}
pieceDB ^= (((bitboard)1) << square);
}
/*******************************************************************************
Dynamic Pawn Eval:
*******************************************************************************/
// -unstoppable passer bonus if the opponent doesnt have any pieces
// - not blocked by own piece and outside of king square.
// - promotion square and pawn is supported by king
// when this is the case, it is pretty much worth a queen, or some fraction of a queen based on distance
// -check if the path is dangerous, if so, is it also defended?
//WHITE:
while (pawn_structure.passed_pawns[WHITE]) {
unsigned char file = bitscan_msb(pawn_structure.passed_pawns[WHITE]);
square =bitscan_msb(b->getPieceBB(WHITE,nPawn) & FileMask(file));
//Rook support bonus:
if (mask::south[square] & b->getPieceBB(WHITE,nRook) ) {
opening_score += ROOK_SUPPORTING_PP_EARLY_BONUS;
endgame_score += ROOK_SUPPORTING_PP_LATE_BONUS;
}
//Pawn Ending:
if (material.no_pieces(BLACK)) {
//check the rule of the square or if the king is supporting:
if (!(mask::rule_of_the_square[WHITE][square] & b->getPieceBB(BLACK, nKing))
|| ((king_circle[WHITE] & ((((bitboard)1) << square)) && (king_circle[WHITE]&RankMask(8))))
){
endgame_score += (GUARANTEED_PROMOTION_VALUE) / ((9) - RankOf(square));
}
// penalize for having a piece in the path:
bitboard blocker = (mask::north[square] & b->getOccupiedBB(WHITE));
if (blocker)
endgame_score += -pp_self_blocking_penalty[RankOf(bitscan_lsb(blocker)) - 2];
}
else {
//Check if the path is blocked:
bitboard blockers = mask::north[square] & (b->getOccupiedBB(BLACK));
unsigned char nearest = bitscan_lsb(blockers);
if (nearest == 64)
endgame_score += pp_clear_path_bonus[7]; //full bonus
else
endgame_score += pp_clear_path_bonus[RankOf(nearest) - 2];
//check if the path is threatened
bitboard threats = mask::north[square] & (attacks[BLACK] ^ (attacks[WHITE] & attacks[BLACK]));
nearest = bitscan_lsb(threats);
if (nearest == 64)
endgame_score += pp_unthreatened_path_bonus[7];
else
endgame_score += pp_unthreatened_path_bonus[RankOf(nearest) - 2];
//TODO: add a bonus if our king can get to the square in front of the pawn
// faster than the enemy king.
}
pawn_structure.passed_pawns[WHITE] ^= (1 << file);
}
//BLACK:
while (pawn_structure.passed_pawns[BLACK]) {
unsigned char file = bitscan_lsb(pawn_structure.passed_pawns[BLACK]);
pawn_structure.passed_pawns[BLACK] ^= (1 << file);
square = bitscan_lsb(b->getPieceBB(BLACK, nPawn) & FileMask(file));
//Rook support bonus:
if (mask::north[square] & b->getPieceBB(BLACK, nRook)) {
opening_score -= ROOK_SUPPORTING_PP_EARLY_BONUS;
endgame_score -= ROOK_SUPPORTING_PP_LATE_BONUS;
}
//Pawn Ending:
if (material.no_pieces(WHITE)) {
// check the rule of the square or if the king is supporting:
if (!(mask::rule_of_the_square[BLACK][square] & b->getPieceBB(WHITE, nKing))
|| ((king_circle[BLACK] & (((bitboard)1) << square))&&(king_circle[BLACK] &RankMask(1)))
){
endgame_score -= (GUARANTEED_PROMOTION_VALUE) / (RankOf(square));
}
// penalize for having a piece in the path:
bitboard blocker = (mask::south[square] & b->getOccupiedBB(WHITE));
if (blocker)
endgame_score -= -pp_self_blocking_penalty[9 - RankOf((bitscan_msb(blocker))) - 2];
}
else {
//Check if the path is blocked:
bitboard blockers = mask::south[square] & (b->getOccupiedBB(WHITE));
unsigned char nearest = bitscan_msb(blockers);
if (nearest == 64)
endgame_score -= pp_clear_path_bonus[7]; //full bonus
else
endgame_score -= pp_clear_path_bonus[9 - RankOf(nearest) - 2];
//check if the path is threatened
bitboard threats = mask::south[square] & (attacks[WHITE] ^ (attacks[BLACK] & attacks[WHITE]));
nearest = bitscan_msb(threats);
if (nearest == 64)
endgame_score -= pp_unthreatened_path_bonus[7];
else
endgame_score -= pp_unthreatened_path_bonus[RankOf(nearest) - 2];
//TODO: add a bonus if our king can get to the square in front of the pawn
// faster than the enemy king.
}
}
/*******************************************************************************
King Threat Score:
*******************************************************************************/
opening_score += ((attackers_weight[WHITE]) * threat_score[king_attackers[WHITE]]) / THREAT_RATIO;
//endgame_score += ((attackers_weight[WHITE]) * threat_score[king_attackers[WHITE]]) / THREAT_RATIO;
opening_score -= ((attackers_weight[BLACK]) * threat_score[king_attackers[BLACK]]) / THREAT_RATIO;
//endgame_score -= ((attackers_weight[BLACK]) * threat_score[king_attackers[BLACK]]) / THREAT_RATIO;
/*******************************************************************************
Material Balance:
*******************************************************************************/
opening_score += b->getMaterialValue(WHITE) - b->getMaterialValue(BLACK);
endgame_score += b->getMaterialValue(WHITE) - b->getMaterialValue(BLACK);
evaluateMaterialTable(&material, opening_score, endgame_score);
/*******************************************************************************
Tapered Eval:
*******************************************************************************/
phase = TOTAL_PHASE - phase;