My idea was to implement traits on Piece that return sight lines, etc. This has
turned out to be much more complex than I thought it would be. Ultimately, I
don't think it's worth the effort.
This bit scanner iterates populated bits in a BitBoard from the trailing (least-significant) end.
Rename BitScanner → LeadingBitScanner.
Factor implementation of these two into a macro.
Clean up iterator returned by BitBoard::occupied_squares
Implement BitBoard::occupied_squares_trailing
- Clean up operator traits: remove the & versions and make the macro do more with less input
- Implement From<Square> for BitBoards: simplify conversion of Squares to BitBoards
- Take BitBoards by value in several places
- Clean up unit tests
This struct computes and stores piece moves per square to speed up computation
of move lists.
Initialize a `static mut` instance once via std::sync::Once, and return a static
reference to it. So far, it computes king and knight moves.
Make BitBoard::empty() and MoveLibrary::new() const functions, enabling static
construction of the MOVE_LIBRARY instance without needing to wrap it in an
Option.
Holy heck I went on a *journey* here. Ultimately, I needed to implement my own
index-based iterator instead of using the Vec's Iterator.
This type establishes some patterns I want to carry forward to other move
generators.
1. The use of a Parameters struct to fully parameterize the move generation
per-color. That lets these types only need a single color-based branch
2. A list of move lists, one list for each of captures, promotions, and quiet
moves.
3. An index-based move iterator.
4. Separate impl for generating bitboard representations of these moves
Additional changes:
- Implement BitBoard::from_square()
- Implement a Square::e5() for tests
This class doesn't implement en passant yet. It also doesn't yet have tests for
the bitboard stuff.
BitBoard::file returns a BitBoard representing the 0-indexed file.
fmt::Display prints a grid of bits in the standard orientation (white on bottom, left to right)
Add asserts to the rank and file constructors to catch out of bounds arguments.
Move position.rs to the position module and create a mod.rs.
Do the same for bitboard.rs in the bitboard modules.
Export Color, Piece, Position, and Square and use crate::Thing directly instead of referring to the symbol in the nested modules.
This struct implements an Iterator that returns the positions of the 1 bits in the u64.
BitBoard takes this iterator and maps it into Squares in the pieces() method.
This is laying the groundwork for an iterator over the pieces in a Position. 👀
