UCI Engine version of pChess for OS X. With version 1.9.2, you get both the stand-alone OS X application, and the UCI Engine (compatible with Sigma Chess and Stockfish).
pChess is a basic chess programme for Macintosh OS X, with nice graphics and a built-in FEN Viewer. It supports Fischer games, copy/paste of FEN positions, SAN Notation, Load and Save, and unlimited Undo/Redo.
Cool Audio and Visual Brain features let you listen and see as it evaluates moves. The opening book includes over 10,000 moves from the ECO (Encyclopedia of Chess Openings). Runs at about 1500 ELO. Comes complete with FutureBasic 5 source code.
New in version 1.9.2 (UCI Edition with Time Control)
- Fixed a bug which caused peaBrain to crash after 99 moves (new max = 512).
- Added UCI Time Controls: Supported commands are: wtime, btime, movestogo, movetime, depth, and infinite.
- UCI Opening Book: Include pBook.txt in the engine folder, and enable UCI option Book = true to enable book openings for the engine.
- Better UCI Info: Hash Percent and Move Score are now scaled more reasonably, and Nodes Per Second is now sent to the GUI.
- Smaller Memory: Default Hash Table has been reduced from 256Mb down to 64Mb. This substantially reduces memory usage (from 280Mb > 80Mb) without incurring significant loss in speed.
- Added Ghosted (i.e. uncaptured) pieces to the captured pieces display in the GUI.
New in version 1.9
- UCI Engine Support (peaBrain is the engine inside pChess).
- Fixed an Asymmetric Pawn evaluation bug introduced in v1.8.
New in version 1.8
- Added Hash Tables and Iterative Deepening. This should speed searches significantly.
- The Opening Book is now bundled and auto-loaded at startup.
- Captured pieces are now displayed in the info area.
- The evaluation is now more subtle, with many improved evaluation features:
- Adjusted the default weights of the knight and bishop, such that the following
conditions will occur: i) B > N > 3P; ii) B + N = R + 1.5P; iii) Q + P = 2R.
Thus, _bishopWt = 330; _knightWt = 320, as per: Tomasz Michniewski (ChessWiki)
- Improved the pawn tropism, added knight tropism, and a bonus for a bishop pair.
- It would previously castle into open (bad!) positions. Now it should only castle
into a position behind a protecting pawn.
- Positional scores have been normalized so as not to exceed material scores. This should help prevent bad trades.
- A bug in quiescenceSearch() which was lowering recapture scores was fixed.
- You can now load and save FEN with enPassant information.
- Clicking a square now shows only legal moves for the piece. Previously, it would show all moves for a piece whether they were legal or not.