diff options
Diffstat (limited to 'src/grossmeister/evaluation.rs')
| -rw-r--r-- | src/grossmeister/evaluation.rs | 27 |
1 files changed, 16 insertions, 11 deletions
diff --git a/src/grossmeister/evaluation.rs b/src/grossmeister/evaluation.rs index 6fc4149..1b57f5a 100644 --- a/src/grossmeister/evaluation.rs +++ b/src/grossmeister/evaluation.rs @@ -4,7 +4,10 @@ use crate::{board::{piece::Piece, color::Color, CastlingSide}, bitboard::{Bitboa use super::Grossmeister; -const PAWN_BONUS: [f32; 64] = [ +/// Score in pawns (not centipawns) +pub type Score = f32; + +const PAWN_BONUS: [Score; 64] = [ // A B C D E F G H 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 0.50, 0.50, 0.50, 0.50, 0.50, 0.50, 0.50, 0.50, @@ -16,7 +19,7 @@ const PAWN_BONUS: [f32; 64] = [ 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 0.00 ]; -const PAWN_BONUS_PASSER_ENDGAME: [f32; 64] = [ +const PAWN_BONUS_PASSER_ENDGAME: [Score; 64] = [ // A B C D E F G H 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, 2.00, @@ -28,7 +31,7 @@ const PAWN_BONUS_PASSER_ENDGAME: [f32; 64] = [ 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, ]; -const KNIGHT_BONUS: [f32; 64] = [ +const KNIGHT_BONUS: [Score; 64] = [ // A B C D E F G H -0.50, -0.40, -0.30, -0.30, -0.30, -0.30, -0.40, -0.50, -0.40, -0.20, 0.00, 0.00, 0.00, 0.00, -0.20, -0.40, @@ -40,7 +43,7 @@ const KNIGHT_BONUS: [f32; 64] = [ -0.50, -0.40, -0.30, -0.30, -0.30, -0.30, -0.40, -0.50, ]; -const BISHOP_BONUS: [f32; 64] = [ +const BISHOP_BONUS: [Score; 64] = [ // A B C D E F G H -0.20, -0.10, -0.10, -0.10, -0.10, -0.10, -0.10, -0.20, -0.10, 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, -0.10, @@ -52,7 +55,7 @@ const BISHOP_BONUS: [f32; 64] = [ -0.20, -0.10, -0.10, -0.10, -0.10, -0.10, -0.10, -0.20, ]; -const ROOK_BONUS: [f32; 64] = [ +const ROOK_BONUS: [Score; 64] = [ // A B C D E F G H 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, 0.05, 0.30, 0.30, 0.30, 0.30, 0.30, 0.30, 0.05, @@ -64,7 +67,7 @@ const ROOK_BONUS: [f32; 64] = [ 0.00, 0.00, 0.00, 0.05, 0.05, 0.00, 0.00, 0.00 ]; -const QUEEN_BONUS: [f32; 64] = [ +const QUEEN_BONUS: [Score; 64] = [ // A B C D E F G H -0.20, -0.10, -0.10, -0.05, -0.05, -0.10, -0.10, -0.20, -0.10, 0.00, 0.00, 0.00, 0.00, 0.00, 0.00, -0.10, @@ -76,7 +79,7 @@ const QUEEN_BONUS: [f32; 64] = [ -0.20, -0.10, -0.10, -0.05, -0.05, -0.10, -0.10, -0.20 ]; -const KING_BONUS: [f32; 64] = [ +const KING_BONUS: [Score; 64] = [ // A B C D E F G H -0.30, -0.40, -0.40, -0.50, -0.50, -0.40, -0.40, -0.30, -0.30, -0.40, -0.40, -0.50, -0.50, -0.40, -0.40, -0.30, @@ -88,7 +91,7 @@ const KING_BONUS: [f32; 64] = [ 0.20, 0.10, 0.30, -0.20, 0.00, 0.10, 0.30, 0.20 ]; -const KING_BONUS_ENGAME: [f32; 64] = [ +const KING_BONUS_ENGAME: [Score; 64] = [ // A B C D E F G H -0.50, -0.40, -0.30, -0.20, -0.20, -0.30, -0.40, -0.50, -0.30, -0.20, -0.10, 0.00, 0.00, -0.10, -0.20, -0.30, @@ -209,7 +212,7 @@ impl Grossmeister { /// Evaluate a position relative to the current player - pub fn evaluate(&self) -> f32 { + pub fn evaluate(&self) -> Score { let color = self.board.color(); let opponent_color = color.flip(); @@ -243,9 +246,11 @@ impl Grossmeister { let phase = self.phase(); let tapered_eval = (middlegame_eval * phase as f32 + endgame_eval * (240 - phase) as f32) / 240.; - (material_advantage + tapered_eval) + let eval = (material_advantage + tapered_eval) .min(if winnable { INFINITY } else { 0.0 }) // Can not score > 0 if not winnable - .max(if loseable { -INFINITY } else { 0.0 }) // Can not score < 0 if not loseable + .max(if loseable { -INFINITY } else { 0.0 }); // Can not score < 0 if not loseable + + (eval * 100.0).round() / 100.0 } /// Count pseudo-legal moves without actually generating them |