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-rw-r--r--model/src/board.rs58
1 files changed, 42 insertions, 16 deletions
diff --git a/model/src/board.rs b/model/src/board.rs
index d7cc69f..b67c13c 100644
--- a/model/src/board.rs
+++ b/model/src/board.rs
@@ -76,6 +76,7 @@ impl CheckersBitBoard {
/// 0,
/// PieceColor::Dark);
/// ```
+ #[must_use]
pub const fn new(pieces: u32, color: u32, kings: u32, turn: PieceColor) -> Self {
Self {
pieces,
@@ -86,6 +87,7 @@ impl CheckersBitBoard {
}
/// Creates a board at the starting position
+ #[must_use]
pub const fn starting_position() -> Self {
const STARTING_BITBOARD: CheckersBitBoard = CheckersBitBoard::new(
0b11100111100111100111110111111011,
@@ -97,6 +99,7 @@ impl CheckersBitBoard {
}
/// Gets the bits that represent where pieces are on the board
+ #[must_use]
pub const fn pieces_bits(self) -> u32 {
self.pieces
}
@@ -106,6 +109,7 @@ impl CheckersBitBoard {
/// # Safety
///
/// This is inherently unsafe, because this also returns the bits of empty squares
+ #[must_use]
pub const fn color_bits(self) -> u32 {
self.color
}
@@ -115,11 +119,13 @@ impl CheckersBitBoard {
/// # Safety
///
/// This is inherently unsafe, because this also returns the bits of empty squares
+ #[must_use]
pub const fn king_bits(self) -> u32 {
self.kings
}
/// The player whose turn it is
+ #[must_use]
pub const fn turn(self) -> PieceColor {
self.turn
}
@@ -130,6 +136,7 @@ impl CheckersBitBoard {
///
/// * `row` - The row. The a file is row 0
/// * `col` - The column. The first rank is column 0
+ #[must_use]
pub fn get_at_row_col(self, row: usize, col: usize) -> Option<Piece> {
if row > 32 || col > 32 {
None
@@ -170,6 +177,7 @@ impl CheckersBitBoard {
/// # Panics
///
/// Panics if `value` is greater than or equal to 32
+ #[must_use]
pub const fn piece_at(self, value: usize) -> bool {
((self.pieces >> value) & 1) == 1
}
@@ -202,6 +210,7 @@ impl CheckersBitBoard {
/// # Safety
///
/// Checking the color at a square that is empty results in undefined behavior
+ #[must_use]
pub const unsafe fn color_at_unchecked(self, value: usize) -> PieceColor {
if ((self.color >> value) & 1) != 0 {
PieceColor::Dark
@@ -234,6 +243,7 @@ impl CheckersBitBoard {
/// # Panics
///
/// Panics if `value` is greater than or equal to 32
+ #[must_use]
pub const fn color_at(self, value: usize) -> Option<PieceColor> {
if self.piece_at(value) {
// safety: if this block runs, then it's already confirmed a piece exists here
@@ -269,6 +279,7 @@ impl CheckersBitBoard {
/// # Safety
///
/// Checking a square that is empty results in undefined behavior
+ #[must_use]
pub const unsafe fn king_at_unchecked(self, value: usize) -> bool {
((self.kings >> value) & 1) == 1
}
@@ -296,6 +307,7 @@ impl CheckersBitBoard {
/// # Panics
///
/// Panics if `value` is greater than or equal to 32
+ #[must_use]
pub const fn king_at(self, value: usize) -> Option<bool> {
if self.piece_at(value) {
// safety: if this block runs, then it's already confirmed a piece exists here
@@ -305,6 +317,8 @@ impl CheckersBitBoard {
}
}
+ /// Change whose turn it is, without modifying the board
+ #[must_use]
pub const fn flip_turn(self) -> Self {
CheckersBitBoard::new(self.pieces, self.color, self.kings, self.turn.flip())
}
@@ -326,6 +340,7 @@ impl CheckersBitBoard {
///
/// Results in undefined behavior if `start` does not contain a piece
// TODO rip out so we don't need to check for both black and white promotion
+ #[must_use]
pub const unsafe fn move_piece_to_unchecked(self, start: usize, dest: usize) -> Self {
// Clears the bit at the starting value
// Sets the bit at the destination value
@@ -368,6 +383,7 @@ impl CheckersBitBoard {
/// # Safety
///
/// This results in undefined behavior if `value` does not contain a piece
+ #[must_use]
const unsafe fn move_piece_forward_unchecked(self, value: usize, amount: usize) -> Self {
self.move_piece_to_unchecked(value, (value + amount) & 31)
}
@@ -388,6 +404,7 @@ impl CheckersBitBoard {
/// # Safety
///
/// This results in undefined behavior if `value` does not contain a piece
+ #[must_use]
const unsafe fn move_piece_backward_unchecked(self, value: usize, amount: usize) -> Self {
self.move_piece_to_unchecked(value, value.wrapping_sub(amount) & 31)
}
@@ -408,6 +425,7 @@ impl CheckersBitBoard {
/// Moving from the left side of the board results in undefined behavior.
/// Moving from the top of the board results in undefined behavior.
/// A `value` which doesn't contain a piece results in undefined behavior.
+ #[must_use]
pub const unsafe fn move_piece_forward_left_unchecked(self, value: usize) -> Self {
self.move_piece_forward_unchecked(value, 7)
}
@@ -428,6 +446,7 @@ impl CheckersBitBoard {
/// Moving from the right side of the board results in undefined behavior.
/// Moving from the top of the board results in undefined behavior.
/// A `value` which doesn't contain a piece results in undefined behavior.
+ #[must_use]
pub const unsafe fn move_piece_forward_right_unchecked(self, value: usize) -> Self {
self.move_piece_forward_unchecked(value, 1)
}
@@ -448,6 +467,7 @@ impl CheckersBitBoard {
/// Moving from the left side of the board results in undefined behavior.
/// Moving from the bottom of the board results in undefined behavior.
/// A `value` which doesn't contain a piece results in undefined behavior.
+ #[must_use]
pub const unsafe fn move_piece_backward_left_unchecked(self, value: usize) -> Self {
self.move_piece_backward_unchecked(value, 1)
}
@@ -468,6 +488,7 @@ impl CheckersBitBoard {
/// Moving from the right side of the board results in undefined behavior.
/// Moving from the bottom of the board results in undefined behavior.
/// A `value` which doesn't contain a piece results in undefined behavior.
+ #[must_use]
pub const unsafe fn move_piece_backward_right_unchecked(self, value: usize) -> Self {
self.move_piece_backward_unchecked(value, 7)
}
@@ -481,6 +502,7 @@ impl CheckersBitBoard {
/// # Panics
///
/// Panics if `value` is greater than or equal to 32
+ #[must_use]
pub const fn clear_piece(self, value: usize) -> Self {
let pieces = self.pieces & !(1 << value);
CheckersBitBoard::new(pieces, self.color, self.kings, self.turn)
@@ -502,15 +524,16 @@ impl CheckersBitBoard {
///
/// Moving from the left side of the board results in undefined behavior.
/// Moving from the top of the board results in undefined behavior
+ #[must_use]
pub const unsafe fn jump_piece_forward_left_unchecked(self, value: usize) -> Self {
- let not_king = !self.king_at_unchecked(value);
+ let is_king = self.king_at_unchecked(value);
let board = self
.move_piece_forward_unchecked(value, 14)
.clear_piece((value + 7) & 31);
- const KING_MASK: u32 = 0b01000001000000000000010000010000;
- if PossibleMoves::has_jumps(board.flip_turn())
- && not_king && (((1 << value) & KING_MASK) == 0)
+ const KING_MASK: u32 = 0b00100000100000100000000000001000;
+ if (is_king || (((1 << value) & KING_MASK) == 0))
+ && PossibleMoves::has_jumps(board.flip_turn())
{
board.flip_turn()
} else {
@@ -534,15 +557,16 @@ impl CheckersBitBoard {
///
/// Moving from the right side of the board results in undefined behavior.
/// Moving from the top of the board results in undefined behavior
+ #[must_use]
pub const unsafe fn jump_piece_forward_right_unchecked(self, value: usize) -> Self {
- let not_king = !self.king_at_unchecked(value);
+ let is_king = self.king_at_unchecked(value);
let board = self
.move_piece_forward_unchecked(value, 2)
.clear_piece((value + 1) & 31);
- const KING_MASK: u32 = 0b01000001000000000000010000010000;
- if PossibleMoves::has_jumps(board.flip_turn())
- && not_king && (((1 << value) & KING_MASK) == 0)
+ const KING_MASK: u32 = 0b00100000100000100000000000001000;
+ if (is_king || (((1 << value) & KING_MASK) == 0))
+ && PossibleMoves::has_jumps(board.flip_turn())
{
board.flip_turn()
} else {
@@ -566,15 +590,16 @@ impl CheckersBitBoard {
///
/// Moving from the left side of the board results in undefined behavior.
/// Moving from the bottom of the board results in undefined behavior
+ #[must_use]
pub const unsafe fn jump_piece_backward_left_unchecked(self, value: usize) -> Self {
- let not_king = !self.king_at_unchecked(value);
+ let is_king = self.king_at_unchecked(value);
let board = self
.move_piece_backward_unchecked(value, 2)
.clear_piece(value.wrapping_sub(1) & 31);
- const KING_MASK: u32 = 0b00000000000010000010000010000010;
- if PossibleMoves::has_jumps(board.flip_turn())
- && not_king && (((1 << value) & KING_MASK) == 0)
+ const KING_MASK: u32 = 0b00000100000100000100000100000000;
+ if (is_king || (((1 << value) & KING_MASK) == 0))
+ && PossibleMoves::has_jumps(board.flip_turn())
{
board.flip_turn()
} else {
@@ -598,15 +623,16 @@ impl CheckersBitBoard {
///
/// Moving from the right side of the board results in undefined behavior.
/// Moving from the bottom of the board results in undefined behavior
+ #[must_use]
pub const unsafe fn jump_piece_backward_right_unchecked(self, value: usize) -> Self {
- let not_king = !self.king_at_unchecked(value);
+ let is_king = self.king_at_unchecked(value);
let board = self
.move_piece_backward_unchecked(value, 14)
.clear_piece(value.wrapping_sub(7) & 31);
- const KING_MASK: u32 = 0b00000000000010000010000010000010;
- if PossibleMoves::has_jumps(board.flip_turn())
- && not_king && (((1 << value) & KING_MASK) == 0)
+ const KING_MASK: u32 = 0b00000100000100000100000100000000;
+ if (is_king || (((1 << value) & KING_MASK) == 0))
+ && PossibleMoves::has_jumps(board.flip_turn())
{
board.flip_turn()
} else {
generated by cgit v1.2.3 (git 2.39.1) at 2026-03-04 10:12:24 +0000