[bpt/emacs.git] / lisp / avoid.el

;;; avoid.el -- make mouse pointer stay out of the way of editing.

;;; Copyright (C) 1993, 1994 Free Software Foundation, Inc.

;; Author: Boris Goldowsky <boris@cs.rochester.edu>
;; Keywords: mouse
;; Version: 1.10

;; This file is part of GNU Emacs.

;; GNU Emacs is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation; either version 2, or (at your option)
;; any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs; see the file COPYING.  If not, write to
;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

;;; Commentary:
;;;
;;; For those who are annoyed by the mouse pointer obscuring text,
;;; this mode moves the mouse pointer - either just a little out of
;;; the way, or all the way to the corner of the frame. 
;;; To use, load or evaluate this file and type M-x mouse-avoidance-mode .
;;; To set up permanently, put this file on your load-path and put the
;;; following in your .emacs: 
;;;
;;; (cond (window-system
;;;        (require 'avoid)
;;;        (mouse-avoidance-mode 'cat-and-mouse)))
;;;
;;; The 'cat-and-mouse can be
;;; 'banish or 'jump or 'animate or 'proteus if you prefer.
;;; See the documentation for function `mouse-avoidance-mode' for
;;; details of the different modes.
;;;
;;; For added silliness, make the animatee animate...
;;; put something similar to the following into your .emacs:
;;;
;;; (cond (window-system
;;;       (setq x-pointer-shape 
;;;	     (eval (nth (random 4)
;;;			'(x-pointer-man x-pointer-spider
;;;			  x-pointer-gobbler x-pointer-gumby))))
;;;       (set-mouse-color (cdr (assoc 'mouse-color (frame-parameters))))))
;;;
;;; For completely random pointer shape, replace the setq above with:
;;; (setq x-pointer-shape (mouse-avoidance-random-shape))
;;; 
;;; Bugs & Warnings:
;;;
;;; - Due to a bug in (mouse-position), this code can cause emacs
;;;   19.22 to crash when deleting a frame if the mouse has not moved
;;;   since creating the frame.  Versions earlier than 19.21 will
;;;   crash more easily; this program should not be used with them.
;;;
;;; - Using this code does slow emacs down.  "banish" mode shouldn't
;;;   ever be too bad though, and on my workstation even "animate" doesn't
;;;   seem to have a noticable effect.
;;;
;;; - There are some situations where it doesn't do what you expect,
;;;   notably when there are long wrapped lines in the buffer.  Since
;;;   there is no low-level command for finding point's position
;;;   on the screen, it can fail to move the pointer when on such a line.

;;; Credits:
;;; This code was helped by all those who contributed suggestions, fixes, and 
;;; additions:
;;; Joe Harrington (and his advisor), for the original inspiration
;;; Ken Manheimer, for dreaming up the Protean mode
;;; Richard Stallman, for the awful cat-and-mouse pun, among other things
;;; Mike Williams, Denis Howe, Bill Benedetto, Chris Moore, Don Morris,
;;; Simon Marshall, and M.S. Ashton, for their feedback.
;;;
;;; Code:

(provide 'avoid)

(defvar mouse-avoidance-mode nil
  "Value is t or a symbol if the mouse pointer should avoid the cursor.
See function mouse-avoidance-mode for possible values.  Changing this
variable is NOT the recommended way to change modes; use the function 
instead.")

(defvar mouse-avoidance-nudge-dist 4
  "*Average distance that mouse will be moved when approached by cursor.
Only applies in mode-avoidance-modes `animate' and `jump'.")

(defvar mouse-avoidance-nudge-var 3
  "*Variability of mouse-avoidance-nudge-dist (which see).")

(defvar mouse-avoidance-animation-delay .01
  "Delay between animation steps, in seconds.")

(defvar mouse-avoidance-threshhold 5
  "*Mouse-pointer's flight distance.
If the cursor gets closer than this, the mouse pointer will move away.
Only applies in mouse-avoidance-modes `animate' and `jump'.")

;; Internal variables for mouse-avoidance-random-shape
(defvar mouse-avoidance-pointer-shapes nil)
(defvar mouse-avoidance-n-pointer-shapes 0)

;;; Functions:

(defun mouse-avoidance-too-close-p ()
  ;;  Return t if mouse pointer and point cursor are too close.
  ;; Acceptable distance is defined by mouse-avoidance-threshhold.
  (let ((mouse (mouse-position)))
    (and (car (cdr mouse))
	 (< (abs (- (car (cdr mouse)) (current-column)))
	    mouse-avoidance-threshhold)
	 (< (abs (- (cdr (cdr mouse)) 
		    (+ (car (cdr (window-edges)))
		       (count-lines (window-start) (point)))))
	    mouse-avoidance-threshhold))))

(defun mouse-avoidance-banish-mouse ()
  ;; Put the mouse pointer in the upper-right corner of the current frame.
  (set-mouse-position (selected-frame) (1- (frame-width)) 0))

(defun mouse-avoidance-nudge-mouse () 
  ;; Push the mouse a little way away, possibly animating the move
  (let* ((cur (mouse-position))
	 (deltax (* (+ mouse-avoidance-nudge-dist 
		       (random mouse-avoidance-nudge-var))
		    (if (zerop (random 2)) 1 -1)))
	 (deltay (* (+ mouse-avoidance-nudge-dist
		       (random mouse-avoidance-nudge-var))
		    (if (zerop (random 2)) 1 -1))))
    (if (or (eq mouse-avoidance-mode 'animate) 
	    (eq mouse-avoidance-mode 'proteus))
	(let ((i 0.0)
	      (color (cdr (assoc 'mouse-color (frame-parameters)))))
	  (while (<= i 1)
	    (set-mouse-position 
	     (car cur) 
	     (mod (+ (car (cdr cur)) (round (* i deltax))) (frame-width))
	     (mod (+ (cdr (cdr cur)) (round (* i deltay))) (frame-height)))
	    (setq i (+ i (/ 1.0 mouse-avoidance-nudge-dist)))
	    (if (eq mouse-avoidance-mode 'proteus)
		(progn
		  (setq x-pointer-shape (mouse-avoidance-random-shape))
		  (set-mouse-color color)))
	    (sit-for mouse-avoidance-animation-delay)))
      (set-mouse-position 
       (car cur)
       (mod (+ (car (cdr cur)) deltax) (window-width))
       (mod (+ (cdr (cdr cur)) deltay) (window-height))))))

(defun mouse-avoidance-random-shape ()
  "Return a random cursor shape.
This assumes that any variable whose name begins with x-pointer- and
has an integer value is a valid cursor shape.  You might want to
redefine this function to suit your own tastes."
  (if (null mouse-avoidance-pointer-shapes)
      (progn
	(setq mouse-avoidance-pointer-shapes
	      (mapcar '(lambda (x) (symbol-value (intern x)))
		      (all-completions "x-pointer-" obarray
				       '(lambda (x) 
					  (and (boundp x)
					       (integerp (symbol-value x)))))))
	(setq mouse-avoidance-n-pointer-shapes 
	      (length mouse-avoidance-pointer-shapes))))
  (nth (random mouse-avoidance-n-pointer-shapes)
       mouse-avoidance-pointer-shapes))

(defun mouse-avoidance-simple-hook ()
  (if (and (mouse-avoidance-keyboard-command (this-command-keys)))
      (progn
	(raise-frame (selected-frame))
	(mouse-avoidance-banish-mouse))))

(defun mouse-avoidance-fancy-hook ()
  (if (and (mouse-avoidance-keyboard-command (this-command-keys))
	   (mouse-avoidance-too-close-p))
      (let ((old-pos (mouse-position)))
	(mouse-avoidance-nudge-mouse)
	(if (not (eq (selected-frame) (car old-pos)))
	    (apply 'set-mouse-position old-pos)))))

(defun mouse-avoidance-keyboard-command (key)
  "Return t if the KEYSEQENCE is composed of keyboard events only.
Returns nil if there are any lists in the key sequence."
  (cond ((null key) nil)		; Null event seems to be
					; returned occasionally.
	((not (vectorp key)) t)		; Strings are keyboard events.
	((catch 'done
	   (let ((i 0)
		 (l (length key)))
	     (while (< i l)
	       (if (listp (aref key i))
		   (throw 'done nil))
	       (setq i (1+ i))))
	   t))))

(defun mouse-avoidance-mode (&optional mode)
  "Set cursor avoidance mode to MODE.
MODE should be one of the symbols `banish', `jump', `animate',
`cat-and-mouse', `proteus', or `none'.

If MODE is nil, toggle mouse avoidance between `none' and `banish'
modes.  Positive numbers and symbols other than the above are treated
as equivalent to `banish'; negative numbers and `-' are equivalent to `none'.

Effects of the different modes: 
 * BANISH: Move the mouse to the upper-right corner on any keypress.
           Also raises the frame.
 * JUMP: If the cursor gets too close to the mouse, displace the mouse
         a random distance & direction.  If this would put it in another,
         overlapping frame, it is put back \(until the next keypress).
 * ANIMATE: As `jump', but shows steps along the way for illusion of motion.
 * CAT-AND-MOUSE: Same as `animate'.
 * PROTEUS: As `animate', but changes the shape of the mouse pointer too.

\(see `mouse-avoidance-threshhold' for definition of \"too close\",
and `mouse-avoidance-nudge-dist' and `mouse-avoidance-nudge-var' for
definition of \"random distance\".)"
  (interactive
   (list (intern (completing-read
		  "Select cursor avoidance technique (SPACE for list): "
		  '(("banish") ("jump") ("animate") ("cat-and-mouse") 
		    ("proteus") ("none"))
		  nil t))))
  (if (eq mode 'cat-and-mouse)
      (setq mode 'animate))
  (setq post-command-hook
	(delete 'mouse-avoidance-simple-hook (append post-command-hook nil)))
  (setq post-command-hook
	(delete 'mouse-avoidance-fancy-hook (append post-command-hook nil)))
  (cond	((eq mode 'none)
	 (setq mouse-avoidance-mode nil))
	((or (eq mode 'jump)
	     (eq mode 'animate)
	     (eq mode 'proteus))
	 (add-hook 'post-command-hook 'mouse-avoidance-fancy-hook)
	 (setq mouse-avoidance-mode mode))
	((or (eq mode 'banish) 
	     (eq mode t)
	     (and (null mode) (null mouse-avoidance-mode))
	     (and mode (> (prefix-numeric-value mode) 0)))
	 (add-hook 'post-command-hook 'mouse-avoidance-simple-hook)
	 (setq mouse-avoidance-mode 'banish))
	(t (setq mouse-avoidance-mode nil))))

(or (assq 'mouse-avoidance-mode minor-mode-alist)
    (setq minor-mode-alist (cons '(mouse-avoidance-mode " Avoid")
				 minor-mode-alist)))

;;; End of avoid.el
Commit	Line	Data
bb5d4e1a RS	1	;;; avoid.el -- make mouse pointer stay out of the way of editing.
bb5d4e1a RS	2
d9f132a8	3	;;; Copyright (C) 1993, 1994 Free Software Foundation, Inc.
bb5d4e1a RS	4
	5	;; Author: Boris Goldowsky <boris@cs.rochester.edu>
	6	;; Keywords: mouse
11db296f	7	;; Version: 1.10
bb5d4e1a RS	8
	9	;; This file is part of GNU Emacs.
	10
	11	;; GNU Emacs is free software; you can redistribute it and/or modify
	12	;; it under the terms of the GNU General Public License as published by
	13	;; the Free Software Foundation; either version 2, or (at your option)
	14	;; any later version.
	15
	16	;; GNU Emacs is distributed in the hope that it will be useful,
	17	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	18	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	19	;; GNU General Public License for more details.
	20
	21	;; You should have received a copy of the GNU General Public License
	22	;; along with GNU Emacs; see the file COPYING. If not, write to
	23	;; the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
	24
	25	;;; Commentary:
	26	;;;
	27	;;; For those who are annoyed by the mouse pointer obscuring text,
	28	;;; this mode moves the mouse pointer - either just a little out of
	29	;;; the way, or all the way to the corner of the frame.
	30	;;; To use, load or evaluate this file and type M-x mouse-avoidance-mode .
	31	;;; To set up permanently, put this file on your load-path and put the
	32	;;; following in your .emacs:
	33	;;;
	34	;;; (cond (window-system
	35	;;; (require 'avoid)
	36	;;; (mouse-avoidance-mode 'cat-and-mouse)))
	37	;;;
978625b7 DM	38	;;; The 'cat-and-mouse can be
978625b7 DM	39	;;; 'banish or 'jump or 'animate or 'proteus if you prefer.
d9f132a8 RS	40	;;; See the documentation for function `mouse-avoidance-mode' for
d9f132a8 RS	41	;;; details of the different modes.
bb5d4e1a RS	42	;;;
	43	;;; For added silliness, make the animatee animate...
	44	;;; put something similar to the following into your .emacs:
	45	;;;
	46	;;; (cond (window-system
	47	;;; (setq x-pointer-shape
	48	;;; (eval (nth (random 4)
	49	;;; '(x-pointer-man x-pointer-spider
	50	;;; x-pointer-gobbler x-pointer-gumby))))
	51	;;; (set-mouse-color (cdr (assoc 'mouse-color (frame-parameters))))))
	52	;;;
	53	;;; For completely random pointer shape, replace the setq above with:
	54	;;; (setq x-pointer-shape (mouse-avoidance-random-shape))
	55	;;;
	56	;;; Bugs & Warnings:
	57	;;;
d9f132a8 RS	58	;;; - Due to a bug in (mouse-position), this code can cause emacs
	59	;;; 19.22 to crash when deleting a frame if the mouse has not moved
	60	;;; since creating the frame. Versions earlier than 19.21 will
	61	;;; crash more easily; this program should not be used with them.
bb5d4e1a RS	62	;;;
	63	;;; - Using this code does slow emacs down. "banish" mode shouldn't
	64	;;; ever be too bad though, and on my workstation even "animate" doesn't
	65	;;; seem to have a noticable effect.
	66	;;;
	67	;;; - There are some situations where it doesn't do what you expect,
	68	;;; notably when there are long wrapped lines in the buffer. Since
	69	;;; there is no low-level command for finding point's position
	70	;;; on the screen, it can fail to move the pointer when on such a line.
bb5d4e1a RS	71
	72	;;; Credits:
	73	;;; This code was helped by all those who contributed suggestions, fixes, and
	74	;;; additions:
	75	;;; Joe Harrington (and his advisor), for the original inspiration
	76	;;; Ken Manheimer, for dreaming up the Protean mode
	77	;;; Richard Stallman, for the awful cat-and-mouse pun, among other things
	78	;;; Mike Williams, Denis Howe, Bill Benedetto, Chris Moore, Don Morris,
	79	;;; Simon Marshall, and M.S. Ashton, for their feedback.
	80	;;;
	81	;;; Code:
	82
	83	(provide 'avoid)
	84
	85	(defvar mouse-avoidance-mode nil
	86	"Value is t or a symbol if the mouse pointer should avoid the cursor.
	87	See function mouse-avoidance-mode for possible values. Changing this
	88	variable is NOT the recommended way to change modes; use the function
	89	instead.")
	90
	91	(defvar mouse-avoidance-nudge-dist 4
	92	"*Average distance that mouse will be moved when approached by cursor.
	93	Only applies in mode-avoidance-modes `animate' and `jump'.")
	94
	95	(defvar mouse-avoidance-nudge-var 3
	96	"*Variability of mouse-avoidance-nudge-dist (which see).")
	97
	98	(defvar mouse-avoidance-animation-delay .01
	99	"Delay between animation steps, in seconds.")
	100
	101	(defvar mouse-avoidance-threshhold 5
	102	"*Mouse-pointer's flight distance.
	103	If the cursor gets closer than this, the mouse pointer will move away.
	104	Only applies in mouse-avoidance-modes `animate' and `jump'.")
	105
	106	;; Internal variables for mouse-avoidance-random-shape
	107	(defvar mouse-avoidance-pointer-shapes nil)
	108	(defvar mouse-avoidance-n-pointer-shapes 0)
	109
	110	;;; Functions:
	111
	112	(defun mouse-avoidance-too-close-p ()
	113	;; Return t if mouse pointer and point cursor are too close.
	114	;; Acceptable distance is defined by mouse-avoidance-threshhold.
	115	(let ((mouse (mouse-position)))
	116	(and (car (cdr mouse))
	117	(< (abs (- (car (cdr mouse)) (current-column)))
	118	mouse-avoidance-threshhold)
	119	(< (abs (- (cdr (cdr mouse))
	120	(+ (car (cdr (window-edges)))
	121	(count-lines (window-start) (point)))))
	122	mouse-avoidance-threshhold))))
	123
	124	(defun mouse-avoidance-banish-mouse ()
	125	;; Put the mouse pointer in the upper-right corner of the current frame.
	126	(set-mouse-position (selected-frame) (1- (frame-width)) 0))
	127
	128	(defun mouse-avoidance-nudge-mouse ()
	129	;; Push the mouse a little way away, possibly animating the move
	130	(let* ((cur (mouse-position))
	131	(deltax (* (+ mouse-avoidance-nudge-dist
	132	(random mouse-avoidance-nudge-var))
	133	(if (zerop (random 2)) 1 -1)))
	134	(deltay (* (+ mouse-avoidance-nudge-dist
135	(random mouse-avoidance-nudge-var))
136	(if (zerop (random 2)) 1 -1))))
137	(if (or (eq mouse-avoidance-mode 'animate)
138	(eq mouse-avoidance-mode 'proteus))
139	(let ((i 0.0)
140	(color (cdr (assoc 'mouse-color (frame-parameters)))))
141	(while (<= i 1)
142	(set-mouse-position
143	(car cur)
d9f132a8 RS	144	(mod (+ (car (cdr cur)) (round (* i deltax))) (frame-width))
d9f132a8 RS	145	(mod (+ (cdr (cdr cur)) (round (* i deltay))) (frame-height)))
bb5d4e1a RS	146	(setq i (+ i (/ 1.0 mouse-avoidance-nudge-dist)))
	147	(if (eq mouse-avoidance-mode 'proteus)
	148	(progn
	149	(setq x-pointer-shape (mouse-avoidance-random-shape))
	150	(set-mouse-color color)))
	151	(sit-for mouse-avoidance-animation-delay)))
	152	(set-mouse-position
	153	(car cur)
	154	(mod (+ (car (cdr cur)) deltax) (window-width))
	155	(mod (+ (cdr (cdr cur)) deltay) (window-height))))))
	156
	157	(defun mouse-avoidance-random-shape ()
	158	"Return a random cursor shape.
	159	This assumes that any variable whose name begins with x-pointer- and
	160	has an integer value is a valid cursor shape. You might want to
	161	redefine this function to suit your own tastes."
	162	(if (null mouse-avoidance-pointer-shapes)
	163	(progn
	164	(setq mouse-avoidance-pointer-shapes
	165	(mapcar '(lambda (x) (symbol-value (intern x)))
	166	(all-completions "x-pointer-" obarray
	167	'(lambda (x)
	168	(and (boundp x)
	169	(integerp (symbol-value x)))))))
	170	(setq mouse-avoidance-n-pointer-shapes
	171	(length mouse-avoidance-pointer-shapes))))
	172	(nth (random mouse-avoidance-n-pointer-shapes)
	173	mouse-avoidance-pointer-shapes))
	174
	175	(defun mouse-avoidance-simple-hook ()
	176	(if (and (mouse-avoidance-keyboard-command (this-command-keys)))
d9f132a8 RS	177	(progn
	178	(raise-frame (selected-frame))
	179	(mouse-avoidance-banish-mouse))))
bb5d4e1a RS	180
	181	(defun mouse-avoidance-fancy-hook ()
	182	(if (and (mouse-avoidance-keyboard-command (this-command-keys))
	183	(mouse-avoidance-too-close-p))
d9f132a8 RS	184	(let ((old-pos (mouse-position)))
	185	(mouse-avoidance-nudge-mouse)
	186	(if (not (eq (selected-frame) (car old-pos)))
	187	(apply 'set-mouse-position old-pos)))))
bb5d4e1a RS	188
	189	(defun mouse-avoidance-keyboard-command (key)
	190	"Return t if the KEYSEQENCE is composed of keyboard events only.
	191	Returns nil if there are any lists in the key sequence."
	192	(cond ((null key) nil) ; Null event seems to be
	193	; returned occasionally.
	194	((not (vectorp key)) t) ; Strings are keyboard events.
	195	((catch 'done
	196	(let ((i 0)
	197	(l (length key)))
	198	(while (< i l)
	199	(if (listp (aref key i))
	200	(throw 'done nil))
	201	(setq i (1+ i))))
	202	t))))
	203
	204	(defun mouse-avoidance-mode (&optional mode)
	205	"Set cursor avoidance mode to MODE.
	206	MODE should be one of the symbols `banish', `jump', `animate',
d9f132a8 RS	207	`cat-and-mouse', `proteus', or `none'.
	208
	209	If MODE is nil, toggle mouse avoidance between `none' and `banish'
	210	modes. Positive numbers and symbols other than the above are treated
	211	as equivalent to `banish'; negative numbers and `-' are equivalent to `none'.
	212
	213	Effects of the different modes:
	214	* BANISH: Move the mouse to the upper-right corner on any keypress.
	215	Also raises the frame.
	216	* JUMP: If the cursor gets too close to the mouse, displace the mouse
	217	a random distance & direction. If this would put it in another,
	218	overlapping frame, it is put back \(until the next keypress).
	219	* ANIMATE: As `jump', but shows steps along the way for illusion of motion.
	220	* CAT-AND-MOUSE: Same as `animate'.
	221	* PROTEUS: As `animate', but changes the shape of the mouse pointer too.
	222
	223	\(see `mouse-avoidance-threshhold' for definition of \"too close\",
	224	and `mouse-avoidance-nudge-dist' and `mouse-avoidance-nudge-var' for
	225	definition of \"random distance\".)"
bb5d4e1a RS	226	(interactive
	227	(list (intern (completing-read
	228	"Select cursor avoidance technique (SPACE for list): "
	229	'(("banish") ("jump") ("animate") ("cat-and-mouse")
	230	("proteus") ("none"))
	231	nil t))))
	232	(if (eq mode 'cat-and-mouse)
	233	(setq mode 'animate))
	234	(setq post-command-hook
	235	(delete 'mouse-avoidance-simple-hook (append post-command-hook nil)))
	236	(setq post-command-hook
	237	(delete 'mouse-avoidance-fancy-hook (append post-command-hook nil)))
	238	(cond ((eq mode 'none)
	239	(setq mouse-avoidance-mode nil))
	240	((or (eq mode 'jump)
	241	(eq mode 'animate)
	242	(eq mode 'proteus))
	243	(add-hook 'post-command-hook 'mouse-avoidance-fancy-hook)
	244	(setq mouse-avoidance-mode mode))
	245	((or (eq mode 'banish)
	246	(eq mode t)
	247	(and (null mode) (null mouse-avoidance-mode))
	248	(and mode (> (prefix-numeric-value mode) 0)))
	249	(add-hook 'post-command-hook 'mouse-avoidance-simple-hook)
	250	(setq mouse-avoidance-mode 'banish))
	251	(t (setq mouse-avoidance-mode nil))))
	252
	253	(or (assq 'mouse-avoidance-mode minor-mode-alist)
	254	(setq minor-mode-alist (cons '(mouse-avoidance-mode " Avoid")
	255	minor-mode-alist)))
	256
	257	;;; End of avoid.el
	258