diff options
| author | mrw1593 <botahamec@outlook.com> | 2021-07-13 17:54:25 -0400 |
|---|---|---|
| committer | mrw1593 <botahamec@outlook.com> | 2021-07-13 17:54:25 -0400 |
| commit | bf9e9af7f45433def26d2d2094a04798cb0282c0 (patch) | |
| tree | 786e145253a329c4da28edc94eae68b719b6d45d /model/src/moves_iter.rs | |
| parent | d2b28aa31a84f43bf5c4f375357e0f013337cdaf (diff) | |
Updated docs and tests
Diffstat (limited to 'model/src/moves_iter.rs')
| -rw-r--r-- | model/src/moves_iter.rs | 287 |
1 files changed, 144 insertions, 143 deletions
diff --git a/model/src/moves_iter.rs b/model/src/moves_iter.rs index 307ee96..ffa59b6 100644 --- a/model/src/moves_iter.rs +++ b/model/src/moves_iter.rs @@ -1,143 +1,144 @@ -use crate::moves::{Move, MoveDirection};
-use crate::possible_moves::PossibleMoves;
-
-const FORWARD_LEFT_SLIDE_SQUARES: [usize; 33] = [
- 1, 3, 3, 4, 6, 6, 7, 8, 9, 12, 12, 12, 13, 14, 15, 16, 17, 19, 19, 20, 21, 22, 23, 24, 27, 27,
- 27, 28, 29, 30, 32, 32, 32,
-];
-const FORWARD_RIGHT_SLIDE_SQUARES: [usize; 33] = [
- 2, 2, 3, 4, 6, 6, 7, 8, 10, 10, 12, 12, 13, 14, 15, 16, 18, 18, 19, 20, 21, 22, 23, 24, 26, 26,
- 27, 28, 29, 30, 32, 32, 32,
-];
-const BACKWARD_LEFT_SLIDE_SQUARES: [usize; 33] = [
- 1, 3, 3, 4, 5, 7, 7, 8, 9, 11, 11, 13, 13, 14, 15, 16, 17, 19, 19, 20, 21, 22, 23, 24, 25, 27,
- 27, 28, 29, 30, 31, 32, 32,
-];
-const BACKWARD_RIGHT_SLIDE_SQUARES: [usize; 33] = [
- 2, 2, 3, 4, 5, 7, 7, 8, 10, 10, 11, 13, 13, 14, 15, 16, 19, 19, 19, 20, 21, 22, 23, 24, 26, 26,
- 27, 28, 29, 30, 31, 32, 32,
-];
-
-const FORWARD_LEFT_JUMP_SQUARES: [usize; 33] = [
- 1, 6, 6, 6, 6, 6, 7, 8, 9, 12, 12, 12, 13, 14, 15, 16, 17, 20, 20, 20, 21, 22, 23, 28, 28, 28,
- 28, 28, 29, 32, 32, 32, 32,
-];
-const FORWARD_RIGHT_JUMP_SQUARES: [usize; 33] = [
- 2, 2, 3, 6, 6, 6, 7, 12, 12, 12, 12, 12, 13, 14, 15, 18, 18, 18, 19, 20, 21, 22, 23, 26, 26,
- 26, 27, 28, 29, 32, 32, 32, 32,
-];
-const BACKWARD_LEFT_JUMP_SQUARES: [usize; 33] = [
- 4, 4, 4, 4, 5, 8, 8, 8, 9, 14, 14, 14, 14, 14, 15, 16, 17, 20, 20, 20, 21, 22, 23, 24, 25, 28,
- 28, 28, 29, 30, 31, 32, 32,
-];
-const BACKWARD_RIGHT_JUMP_SQUARES: [usize; 33] = [
- 2, 2, 3, 4, 5, 10, 10, 10, 10, 10, 11, 14, 14, 14, 15, 20, 20, 20, 20, 20, 21, 22, 23, 26, 26,
- 26, 27, 28, 29, 30, 31, 32, 32,
-];
-
-static SLIDE_ARRAYS: [[usize; 33]; 4] = [
- FORWARD_LEFT_SLIDE_SQUARES,
- FORWARD_RIGHT_SLIDE_SQUARES,
- BACKWARD_LEFT_SLIDE_SQUARES,
- BACKWARD_RIGHT_SLIDE_SQUARES,
-];
-
-static JUMP_ARRAYS: [[usize; 33]; 4] = [
- FORWARD_LEFT_JUMP_SQUARES,
- FORWARD_RIGHT_JUMP_SQUARES,
- BACKWARD_LEFT_JUMP_SQUARES,
- BACKWARD_RIGHT_JUMP_SQUARES,
-];
-
-pub struct PossibleMovesIter {
- possible_moves: PossibleMoves,
- current_square: usize,
- current_direction: MoveDirection,
- movers: u32,
- squares: &'static [usize; 33],
-}
-
-impl From<PossibleMoves> for PossibleMovesIter {
- fn from(possible_moves: PossibleMoves) -> Self {
- Self {
- possible_moves,
- current_square: 0,
- current_direction: MoveDirection::ForwardLeft,
- movers: possible_moves.forward_left_bits(),
- squares: unsafe {
- if possible_moves.can_jump() {
- JUMP_ARRAYS.get_unchecked(0)
- } else {
- SLIDE_ARRAYS.get_unchecked(0)
- }
- },
- }
- }
-}
-
-impl Iterator for PossibleMovesIter {
- type Item = Move;
-
- fn next(&mut self) -> Option<Self::Item> {
- loop {
- if self.current_square == 32 {
- if self.current_direction != MoveDirection::BackwardRight {
- self.current_square = 0;
- // safety: only results in undefined variant if equal to backward right
- // this has already been checked for
- self.current_direction =
- unsafe { std::mem::transmute((self.current_direction as u8) + 1) };
- self.movers = self
- .possible_moves
- .get_direction_bits(self.current_direction);
-
- // safety: the max value of the enum is 3
- unsafe {
- self.squares = &*(self.squares as *const [usize; 33]).add(1);
- }
- } else {
- return None;
- }
- }
-
- if (self.movers >> self.current_square) & 1 != 0 {
- let next_move = Move::new(
- self.current_square,
- self.current_direction,
- self.possible_moves.can_jump(),
- );
-
- // safety: self.current_square will never be > 32
- // squares does not contain such a value
- unsafe {
- self.current_square = *self.squares.get_unchecked(self.current_square);
- }
-
- return Some(next_move);
- }
-
- if self.current_square != 32 {
- // safety: self.current_square will never be > 32
- // squares does not contain such a value
- unsafe {
- self.current_square = *self.squares.get_unchecked(self.current_square);
- }
- }
- }
- }
-
- fn size_hint(&self) -> (usize, Option<usize>) {
- (
- 0,
- Some(
- (32 - self.current_square)
- + 32 * match self.current_direction {
- MoveDirection::ForwardLeft => 3,
- MoveDirection::ForwardRight => 2,
- MoveDirection::BackwardLeft => 1,
- MoveDirection::BackwardRight => 0,
- },
- ),
- )
- }
-}
+use crate::moves::{Move, MoveDirection}; +use crate::possible_moves::PossibleMoves; + +const FORWARD_LEFT_SLIDE_SQUARES: [usize; 33] = [ + 1, 3, 3, 4, 6, 6, 7, 8, 9, 12, 12, 12, 13, 14, 15, 16, 17, 19, 19, 20, 21, 22, 23, 24, 27, 27, + 27, 28, 29, 30, 32, 32, 32, +]; +const FORWARD_RIGHT_SLIDE_SQUARES: [usize; 33] = [ + 2, 2, 3, 4, 6, 6, 7, 8, 10, 10, 12, 12, 13, 14, 15, 16, 18, 18, 19, 20, 21, 22, 23, 24, 26, 26, + 27, 28, 29, 30, 32, 32, 32, +]; +const BACKWARD_LEFT_SLIDE_SQUARES: [usize; 33] = [ + 1, 3, 3, 4, 5, 7, 7, 8, 9, 11, 11, 13, 13, 14, 15, 16, 17, 19, 19, 20, 21, 22, 23, 24, 25, 27, + 27, 28, 29, 30, 31, 32, 32, +]; +const BACKWARD_RIGHT_SLIDE_SQUARES: [usize; 33] = [ + 2, 2, 3, 4, 5, 7, 7, 8, 10, 10, 11, 13, 13, 14, 15, 16, 19, 19, 19, 20, 21, 22, 23, 24, 26, 26, + 27, 28, 29, 30, 31, 32, 32, +]; + +const FORWARD_LEFT_JUMP_SQUARES: [usize; 33] = [ + 1, 6, 6, 6, 6, 6, 7, 8, 9, 12, 12, 12, 13, 14, 15, 16, 17, 20, 20, 20, 21, 22, 23, 28, 28, 28, + 28, 28, 29, 32, 32, 32, 32, +]; +const FORWARD_RIGHT_JUMP_SQUARES: [usize; 33] = [ + 2, 2, 3, 6, 6, 6, 7, 12, 12, 12, 12, 12, 13, 14, 15, 18, 18, 18, 19, 20, 21, 22, 23, 26, 26, + 26, 27, 28, 29, 32, 32, 32, 32, +]; +const BACKWARD_LEFT_JUMP_SQUARES: [usize; 33] = [ + 4, 4, 4, 4, 5, 8, 8, 8, 9, 14, 14, 14, 14, 14, 15, 16, 17, 20, 20, 20, 21, 22, 23, 24, 25, 28, + 28, 28, 29, 30, 31, 32, 32, +]; +const BACKWARD_RIGHT_JUMP_SQUARES: [usize; 33] = [ + 2, 2, 3, 4, 5, 10, 10, 10, 10, 10, 11, 14, 14, 14, 15, 20, 20, 20, 20, 20, 21, 22, 23, 26, 26, + 26, 27, 28, 29, 30, 31, 32, 32, +]; + +static SLIDE_ARRAYS: [[usize; 33]; 4] = [ + FORWARD_LEFT_SLIDE_SQUARES, + FORWARD_RIGHT_SLIDE_SQUARES, + BACKWARD_LEFT_SLIDE_SQUARES, + BACKWARD_RIGHT_SLIDE_SQUARES, +]; + +static JUMP_ARRAYS: [[usize; 33]; 4] = [ + FORWARD_LEFT_JUMP_SQUARES, + FORWARD_RIGHT_JUMP_SQUARES, + BACKWARD_LEFT_JUMP_SQUARES, + BACKWARD_RIGHT_JUMP_SQUARES, +]; + +pub struct PossibleMovesIter { + possible_moves: PossibleMoves, + current_square: usize, + current_direction: MoveDirection, + movers: u32, + squares: &'static [usize; 33], +} + +impl From<PossibleMoves> for PossibleMovesIter { + fn from(possible_moves: PossibleMoves) -> Self { + Self { + possible_moves, + current_square: 0, + current_direction: MoveDirection::ForwardLeft, + movers: possible_moves.forward_left_bits(), + squares: unsafe { + if possible_moves.can_jump() { + JUMP_ARRAYS.get_unchecked(0) + } else { + SLIDE_ARRAYS.get_unchecked(0) + } + }, + } + } +} + +impl Iterator for PossibleMovesIter { + type Item = Move; + + fn next(&mut self) -> Option<Self::Item> { + loop { + if self.current_square == 32 { + if self.current_direction != MoveDirection::BackwardRight { + self.current_square = 0; + // safety: only results in undefined variant if equal to backward right + // this has already been checked for + self.current_direction = + unsafe { std::mem::transmute((self.current_direction as u8) + 1) }; + self.movers = self + .possible_moves + .get_direction_bits(self.current_direction); + + // safety: this iterator stops returning values before this + // can result in undefined behavior + unsafe { + self.squares = &*(self.squares as *const [usize; 33]).add(1); + } + } else { + return None; + } + } + + if (self.movers >> self.current_square) & 1 != 0 { + let next_move = Move::new( + self.current_square, + self.current_direction, + self.possible_moves.can_jump(), + ); + + // safety: self.current_square will never be > 32 + // squares does not contain such a value + unsafe { + self.current_square = *self.squares.get_unchecked(self.current_square); + } + + return Some(next_move); + } + + if self.current_square != 32 { + // safety: self.current_square will never be > 32 + // squares does not contain such a value + unsafe { + self.current_square = *self.squares.get_unchecked(self.current_square); + } + } + } + } + + fn size_hint(&self) -> (usize, Option<usize>) { + ( + 0, + Some( + (32 - self.current_square) + + 32 * match self.current_direction { + MoveDirection::ForwardLeft => 3, + MoveDirection::ForwardRight => 2, + MoveDirection::BackwardLeft => 1, + MoveDirection::BackwardRight => 0, + }, + ), + ) + } +} |
