diff options
| author | John Wiegley <johnw@newartisans.com> | 2002-03-28 08:29:09 +0000 |
|---|---|---|
| committer | John Wiegley <johnw@newartisans.com> | 2002-03-28 08:29:09 +0000 |
| commit | fc23f824fa3ea525251cf71b6fc0c277c30ed398 (patch) | |
| tree | da6d8bceff255867821c1a57fbcbcdc4a3aa3b69 /chess-standard.el | |
| parent | 871e9bb270b35c621265fc56ec582bdd39900e2a (diff) | |
Made the display code into part of the core library.
Diffstat (limited to 'chess-standard.el')
| -rw-r--r-- | chess-standard.el | 30 |
1 files changed, 18 insertions, 12 deletions
diff --git a/chess-standard.el b/chess-standard.el index b70c028..68c207c 100644 --- a/chess-standard.el +++ b/chess-standard.el @@ -15,7 +15,7 @@ ;; that could make it to e4 (either by taking a piece, or by moving ;; there) you'd call: ;; -;; (chess-standard-search POSITION (chess-coord-to-index "e4") ?P) +;; (chess-standard-search-position POSITION (chess-coord-to-index "e4") ?P) ;; ;; This returns a list of indices specifying all white pawns that ;; could reach e4 in one move. NOTE: The general search order is from @@ -29,7 +29,7 @@ ;;; Code: -(defun chess-standard-validate (ply) +(defun chess-standard-validate-ply (ply &optoinal search-func) "Validate the given PLY against standard chess rules." (let* ((pos (chess-ply-pos ply)) (color (chess-pos-side-to-move pos)) @@ -55,11 +55,12 @@ (signal 'chess-illegal "Cannot move on top of your own pieces"))) - (unless (chess-standard-search pos target piece) + (unless (funcall (or search-func + 'chess-standard-search-position) pos target piece) (signal 'chess-illegal "Illegal move")))) -(defun chess-standard-search (position target piece) - "Look on POSITION from position TARGET for PIECE. +(defun chess-standard-search-position (position target piece) + "Look on POSITION from TARGET for a PIECE that can move there. This routine looks along legal paths of movement for PIECE. If PIECE is t or nil, legal piece movements for any piece of that @@ -80,8 +81,8 @@ indices which indicate where a piece may have moved from." (setq candidates (list t)) (dolist (p '(?P ?R ?N ?B ?K ?Q)) (nconc candidates - (chess-standard-search position target - (if piece p (downcase p))))) + (chess-standard-search-position position target + (if piece p (downcase p))))) (setq candidates (cdr candidates))) ;; pawn movement, which is diagonal 1 when taking, but forward @@ -166,21 +167,26 @@ indices which indicate where a piece may have moved from." (chess-pos-can-castle position (if c ?K ?k)) (setq pos (chess-rf-to-index rank 5)) (chess-pos-piece-p position pos ? ) - (not (chess-standard-search position pos (not c))) + (not (chess-standard-search-position position + pos (not c))) (setq pos (chess-rf-to-index rank 6)) (chess-pos-piece-p position pos ? ) - (not (chess-standard-search position pos (not c)))) + (not (chess-standard-search-position position + pos (not c)))) (and (equal target (cons rank 2)) (chess-pos-can-castle position (if c ?Q ?q)) (setq pos (chess-rf-to-index rank 1)) (chess-pos-piece-p position pos ? ) - (not (chess-standard-search position pos (not c))) + (not (chess-standard-search-position position + pos (not c))) (setq pos (chess-rf-to-index rank 2)) (chess-pos-piece-p position pos ? ) - (not (chess-standard-search position pos (not c))) + (not (chess-standard-search-position position + pos (not c))) (setq pos (chess-rf-to-index rank 3)) (chess-pos-piece-p position pos ? ) - (not (chess-standard-search position pos (not c)))))) + (not (chess-standard-search-position position + pos (not c)))))) (setq candidates (list (chess-rf-to-index rank 4)))))) ;; the knight is a zesty little piece; there may be more than |