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

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

;;; Copyright (C) 1993 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 'animate can be 'jump or 'banish or 'protean if you prefer.
;;;
;;; 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:
;;;
;;; - THIS CODE IS FOR USE WITH FSF EMACS 19.21 or later.
;;;   It can cause earlier versions of emacs to crash, due to a bug in the
;;;   mouse code. 
;;;
;;; - 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))) (window-width))
	     (mod (+ (cdr (cdr cur)) (round (* i deltay))) (window-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)))
      (mouse-avoidance-banish-mouse)))

(defun mouse-avoidance-fancy-hook ()
  (if (and (mouse-avoidance-keyboard-command (this-command-keys))
	   (mouse-avoidance-too-close-p))
      (mouse-avoidance-nudge-mouse)))

(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', or `none'.  `Animate' is the same as `cat-and-mouse'.
If MODE is nil, toggle mouse avoidance.  Positive numbers and
symbols other than the above are treated as equivalent to `banish';
negative numbers and `-' are equivalent to `none'."
  (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.
	2
	3	;;; Copyright (C) 1993 Free Software Foundation, Inc.
	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	;;;
	38	;;; The 'animate can be 'jump or 'banish or 'protean if you prefer.
	39	;;;
	40	;;; For added silliness, make the animatee animate...
	41	;;; put something similar to the following into your .emacs:
	42	;;;
	43	;;; (cond (window-system
	44	;;; (setq x-pointer-shape
	45	;;; (eval (nth (random 4)
	46	;;; '(x-pointer-man x-pointer-spider
	47	;;; x-pointer-gobbler x-pointer-gumby))))
	48	;;; (set-mouse-color (cdr (assoc 'mouse-color (frame-parameters))))))
	49	;;;
	50	;;; For completely random pointer shape, replace the setq above with:
	51	;;; (setq x-pointer-shape (mouse-avoidance-random-shape))
	52	;;;
	53	;;; Bugs & Warnings:
	54	;;;
	55	;;; - THIS CODE IS FOR USE WITH FSF EMACS 19.21 or later.
	56	;;; It can cause earlier versions of emacs to crash, due to a bug in the
	57	;;; mouse code.
	58	;;;
	59	;;; - Using this code does slow emacs down. "banish" mode shouldn't
	60	;;; ever be too bad though, and on my workstation even "animate" doesn't
	61	;;; seem to have a noticable effect.
	62	;;;
	63	;;; - There are some situations where it doesn't do what you expect,
	64	;;; notably when there are long wrapped lines in the buffer. Since
	65	;;; there is no low-level command for finding point's position
	66	;;; on the screen, it can fail to move the pointer when on such a line.
bb5d4e1a RS	67
	68	;;; Credits:
	69	;;; This code was helped by all those who contributed suggestions, fixes, and
	70	;;; additions:
	71	;;; Joe Harrington (and his advisor), for the original inspiration
	72	;;; Ken Manheimer, for dreaming up the Protean mode
	73	;;; Richard Stallman, for the awful cat-and-mouse pun, among other things
	74	;;; Mike Williams, Denis Howe, Bill Benedetto, Chris Moore, Don Morris,
	75	;;; Simon Marshall, and M.S. Ashton, for their feedback.
	76	;;;
	77	;;; Code:
	78
	79	(provide 'avoid)
	80
	81	(defvar mouse-avoidance-mode nil
	82	"Value is t or a symbol if the mouse pointer should avoid the cursor.
	83	See function mouse-avoidance-mode for possible values. Changing this
	84	variable is NOT the recommended way to change modes; use the function
	85	instead.")
	86
	87	(defvar mouse-avoidance-nudge-dist 4
	88	"*Average distance that mouse will be moved when approached by cursor.
	89	Only applies in mode-avoidance-modes `animate' and `jump'.")
	90
	91	(defvar mouse-avoidance-nudge-var 3
	92	"*Variability of mouse-avoidance-nudge-dist (which see).")
	93
	94	(defvar mouse-avoidance-animation-delay .01
	95	"Delay between animation steps, in seconds.")
	96
	97	(defvar mouse-avoidance-threshhold 5
	98	"*Mouse-pointer's flight distance.
	99	If the cursor gets closer than this, the mouse pointer will move away.
	100	Only applies in mouse-avoidance-modes `animate' and `jump'.")
	101
	102	;; Internal variables for mouse-avoidance-random-shape
	103	(defvar mouse-avoidance-pointer-shapes nil)
	104	(defvar mouse-avoidance-n-pointer-shapes 0)
	105
	106	;;; Functions:
	107
	108	(defun mouse-avoidance-too-close-p ()
	109	;; Return t if mouse pointer and point cursor are too close.
	110	;; Acceptable distance is defined by mouse-avoidance-threshhold.
	111	(let ((mouse (mouse-position)))
	112	(and (car (cdr mouse))
	113	(< (abs (- (car (cdr mouse)) (current-column)))
	114	mouse-avoidance-threshhold)
	115	(< (abs (- (cdr (cdr mouse))
	116	(+ (car (cdr (window-edges)))
	117	(count-lines (window-start) (point)))))
	118	mouse-avoidance-threshhold))))
	119
	120	(defun mouse-avoidance-banish-mouse ()
	121	;; Put the mouse pointer in the upper-right corner of the current frame.
	122	(set-mouse-position (selected-frame) (1- (frame-width)) 0))
	123
	124	(defun mouse-avoidance-nudge-mouse ()
	125	;; Push the mouse a little way away, possibly animating the move
	126	(let* ((cur (mouse-position))
	127	(deltax (* (+ mouse-avoidance-nudge-dist
	128	(random mouse-avoidance-nudge-var))
	129	(if (zerop (random 2)) 1 -1)))
	130	(deltay (* (+ mouse-avoidance-nudge-dist
131	(random mouse-avoidance-nudge-var))
132	(if (zerop (random 2)) 1 -1))))
133	(if (or (eq mouse-avoidance-mode 'animate)
134	(eq mouse-avoidance-mode 'proteus))
135	(let ((i 0.0)
136	(color (cdr (assoc 'mouse-color (frame-parameters)))))
137	(while (<= i 1)
138	(set-mouse-position
139	(car cur)
140	(mod (+ (car (cdr cur)) (round (* i deltax))) (window-width))
141	(mod (+ (cdr (cdr cur)) (round (* i deltay))) (window-height)))
142	(setq i (+ i (/ 1.0 mouse-avoidance-nudge-dist)))
143	(if (eq mouse-avoidance-mode 'proteus)
144	(progn
145	(setq x-pointer-shape (mouse-avoidance-random-shape))
146	(set-mouse-color color)))
147	(sit-for mouse-avoidance-animation-delay)))
148	(set-mouse-position
149	(car cur)
150	(mod (+ (car (cdr cur)) deltax) (window-width))
151	(mod (+ (cdr (cdr cur)) deltay) (window-height))))))
152
153	(defun mouse-avoidance-random-shape ()
154	"Return a random cursor shape.
155	This assumes that any variable whose name begins with x-pointer- and
156	has an integer value is a valid cursor shape. You might want to
157	redefine this function to suit your own tastes."
158	(if (null mouse-avoidance-pointer-shapes)
159	(progn
160	(setq mouse-avoidance-pointer-shapes
161	(mapcar '(lambda (x) (symbol-value (intern x)))
162	(all-completions "x-pointer-" obarray
163	'(lambda (x)
164	(and (boundp x)
165	(integerp (symbol-value x)))))))
166	(setq mouse-avoidance-n-pointer-shapes
167	(length mouse-avoidance-pointer-shapes))))
168	(nth (random mouse-avoidance-n-pointer-shapes)
169	mouse-avoidance-pointer-shapes))
170
171	(defun mouse-avoidance-simple-hook ()
172	(if (and (mouse-avoidance-keyboard-command (this-command-keys)))
173	(mouse-avoidance-banish-mouse)))
174
175	(defun mouse-avoidance-fancy-hook ()
176	(if (and (mouse-avoidance-keyboard-command (this-command-keys))
177	(mouse-avoidance-too-close-p))
178	(mouse-avoidance-nudge-mouse)))
179
180	(defun mouse-avoidance-keyboard-command (key)
181	"Return t if the KEYSEQENCE is composed of keyboard events only.
182	Returns nil if there are any lists in the key sequence."
183	(cond ((null key) nil) ; Null event seems to be
184	; returned occasionally.
185	((not (vectorp key)) t) ; Strings are keyboard events.
186	((catch 'done
187	(let ((i 0)
188	(l (length key)))
189	(while (< i l)
190	(if (listp (aref key i))
191	(throw 'done nil))
192	(setq i (1+ i))))
193	t))))
194
195	(defun mouse-avoidance-mode (&optional mode)
196	"Set cursor avoidance mode to MODE.
197	MODE should be one of the symbols `banish', `jump', `animate',
198	`cat-and-mouse', or `none'. `Animate' is the same as `cat-and-mouse'.
199	If MODE is nil, toggle mouse avoidance. Positive numbers and
200	symbols other than the above are treated as equivalent to `banish';
201	negative numbers and `-' are equivalent to `none'."
202	(interactive
203	(list (intern (completing-read
204	"Select cursor avoidance technique (SPACE for list): "
205	'(("banish") ("jump") ("animate") ("cat-and-mouse")
206	("proteus") ("none"))
207	nil t))))
208	(if (eq mode 'cat-and-mouse)
209	(setq mode 'animate))
210	(setq post-command-hook
211	(delete 'mouse-avoidance-simple-hook (append post-command-hook nil)))
212	(setq post-command-hook
213	(delete 'mouse-avoidance-fancy-hook (append post-command-hook nil)))
214	(cond ((eq mode 'none)
215	(setq mouse-avoidance-mode nil))
216	((or (eq mode 'jump)
217	(eq mode 'animate)
218	(eq mode 'proteus))
219	(add-hook 'post-command-hook 'mouse-avoidance-fancy-hook)
220	(setq mouse-avoidance-mode mode))
221	((or (eq mode 'banish)
222	(eq mode t)
223	(and (null mode) (null mouse-avoidance-mode))
224	(and mode (> (prefix-numeric-value mode) 0)))
225	(add-hook 'post-command-hook 'mouse-avoidance-simple-hook)
226	(setq mouse-avoidance-mode 'banish))
227	(t (setq mouse-avoidance-mode nil))))
228
229	(or (assq 'mouse-avoidance-mode minor-mode-alist)
230	(setq minor-mode-alist (cons '(mouse-avoidance-mode " Avoid")
231	minor-mode-alist)))
232
233	;;; End of avoid.el
234