1 ;;; avoid.el -- make mouse pointer stay out of the way of editing.
3 ;;; Copyright (C) 1993, 1994 Free Software Foundation, Inc.
5 ;; Author: Boris Goldowsky <boris@cs.rochester.edu>
9 ;; This file is part of GNU Emacs.
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)
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.
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.
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:
34 ;;; (cond (window-system
36 ;;; (mouse-avoidance-mode 'animate)))
38 ;;; The 'animate can be 'jump or 'banish or 'exile or 'protean if you prefer.
39 ;;; See the documentation for function `mouse-avoidance-mode' for
40 ;;; details of the different modes.
42 ;;; For added silliness, make the animatee animate...
43 ;;; put something similar to the following into your .emacs:
45 ;;; (cond (window-system
46 ;;; (setq x-pointer-shape
47 ;;; (eval (nth (random 4)
48 ;;; '(x-pointer-man x-pointer-spider
49 ;;; x-pointer-gobbler x-pointer-gumby))))
50 ;;; (set-mouse-color (cdr (assoc 'mouse-color (frame-parameters))))))
52 ;;; For completely random pointer shape, replace the setq above with:
53 ;;; (setq x-pointer-shape (mouse-avoidance-random-shape))
55 ;;; Bugs / Warnings / To-Do:
57 ;;; - Using this code does slow emacs down. "banish" mode shouldn't
58 ;;; ever be too bad though, and on my workstation even "animate" doesn't
59 ;;; seem to have a noticable effect during editing.
61 ;;; - It should find out where any overlapping frames are and avoid them,
62 ;;; rather than always raising the frame.
65 ;;; This code was helped by all those who contributed suggestions,
66 ;;; fixes, and additions
67 ;;; Joe Harrington (and his advisor), for the original inspiration.
68 ;;; Ken Manheimer, for dreaming up the Protean mode.
69 ;;; Richard Stallman, for the awful cat-and-mouse pun, among other things.
70 ;;; Mike Williams, Denis Howe, Bill Benedetto, Chris Moore, Don Morris,
71 ;;; Simon Marshall, and M.S. Ashton, for their feedback.
77 (defvar mouse-avoidance-mode nil
78 "Value is t or a symbol if the mouse pointer should avoid the cursor.
79 See function `mouse-avoidance-mode' for possible values. Changing this
80 variable is NOT the recommended way to change modes; use that function
83 (defvar mouse-avoidance-nudge-dist
15
84 "*Average distance that mouse will be moved when approached by cursor.
85 Only applies in mouse-avoidance-mode `jump' and its derivatives.
86 For best results make this larger than `mouse-avoidance-threshold'.")
88 (defvar mouse-avoidance-nudge-var
10
89 "*Variability of `mouse-avoidance-nudge-dist' (which see).")
91 (defvar mouse-avoidance-animation-delay
.01
92 "Delay between animation steps, in seconds.")
94 (defvar mouse-avoidance-threshold
5
95 "*Mouse-pointer's flight distance.
96 If the cursor gets closer than this, the mouse pointer will move away.
97 Only applies in mouse-avoidance-modes `animate' and `jump'.")
100 (defvar mouse-avoidance-state nil
)
101 (defvar mouse-avoidance-pointer-shapes nil
)
102 (defvar mouse-avoidance-n-pointer-shapes
0)
106 (defun mouse-avoidance-point-position ()
107 "Return the position of point as (FRAME X . Y).
108 Analogous to mouse-position."
109 (let* ((w (selected-window))
110 (edges (window-edges w
))
112 (compute-motion (max (window-start w
) (point-min)) ; start pos
113 ;; window-start can be < point-min if the
114 ;; latter has changed since the last redisplay
117 (cons (window-width) (window-height)); stop XY: none
118 (1- (window-width)) ; width
119 (cons (window-hscroll w
) 0) ; 0 may not be right?
121 ;; compute-motion returns (pos HPOS VPOS prevhpos contin)
122 ;; we want: (frame hpos . vpos)
123 (cons (selected-frame)
124 (cons (+ (car edges
) (car (cdr list
)))
125 (+ (car (cdr edges
)) (car (cdr (cdr list
))))))))
127 ;(defun mouse-avoidance-point-position-test ()
129 ; (message (format "point=%s mouse=%s"
130 ; (cdr (mouse-avoidance-point-position))
131 ; (cdr (mouse-position)))))
133 (defun mouse-avoidance-set-mouse-position (pos)
134 ;; Carefully set mouse position to given position (X . Y)
135 ;; Ideally, should check if X,Y is in the current frame, and if not,
136 ;; leave the mouse where it was. However, this is currently
137 ;; difficult to do, so we just raise the frame to avoid frame switches.
138 ;; Returns t if it moved the mouse.
139 (let ((f (selected-frame)))
141 (set-mouse-position f
(car pos
) (cdr pos
))
144 (defun mouse-avoidance-too-close-p (mouse)
145 ;; Return t if mouse pointer and point cursor are too close.
146 ;; Acceptable distance is defined by mouse-avoidance-threshold.
147 (let ((point (mouse-avoidance-point-position)))
148 (and (eq (car mouse
) (car point
))
150 (< (abs (- (car (cdr mouse
)) (car (cdr point
))))
151 mouse-avoidance-threshold
)
152 (< (abs (- (cdr (cdr mouse
)) (cdr (cdr point
))))
153 mouse-avoidance-threshold
))))
155 (defun mouse-avoidance-banish-destination ()
156 "The position to which mouse-avoidance-mode `banish' moves the mouse.
157 You can redefine this if you want the mouse banished to a different corner."
158 (cons (1- (frame-width))
161 (defun mouse-avoidance-banish-mouse ()
162 ;; Put the mouse pointer in the upper-right corner of the current frame.
163 (mouse-avoidance-set-mouse-position (mouse-avoidance-banish-destination)))
165 (defsubst mouse-avoidance-delta
(cur delta dist var min max
)
166 ;; Decide how far to move in either dimension.
167 ;; Args are the CURRENT location, the desired DELTA for
168 ;; warp-conservation, the DISTANCE we like to move, the VARIABILITY
169 ;; in distance allowed, and the MIN and MAX possible window positions.
170 ;; Returns something as close to DELTA as possible withing the constraints.
171 (let ((L1 (max (- min cur
) (+ (- dist
) (- var
))))
172 (R1 (+ (- dist
) var
))
173 (L2 (+ dist
(- var
)))
174 (R2 (min (- max cur
) (+ dist var
))))
175 (if (< R1
(- min cur
)) (setq L1 nil R1 nil
))
176 (if (> L2
(- max cur
)) (setq L2 nil R2 nil
))
177 (cond ((and L1
(< delta L1
)) L1
)
178 ((and R1
(< delta R1
)) delta
)
179 ((and R1
(< delta
0)) R1
)
180 ((and L2
(< delta L2
)) L2
)
181 ((and R2
(< delta R2
)) delta
)
186 (defun mouse-avoidance-nudge-mouse ()
187 ;; Push the mouse a little way away, possibly animating the move
188 ;; For these modes, state keeps track of the total offset that we've
189 ;; accumulated, and tries to keep it close to zero.
190 (let* ((cur (mouse-position))
191 (cur-frame (car cur
))
193 (deltax (mouse-avoidance-delta
194 (car cur-pos
) (- (random mouse-avoidance-nudge-var
)
195 (car mouse-avoidance-state
))
196 mouse-avoidance-nudge-dist mouse-avoidance-nudge-var
198 (deltay (mouse-avoidance-delta
199 (cdr cur-pos
) (- (random mouse-avoidance-nudge-var
)
200 (cdr mouse-avoidance-state
))
201 mouse-avoidance-nudge-dist mouse-avoidance-nudge-var
203 (setq mouse-avoidance-state
204 (cons (+ (car mouse-avoidance-state
) deltax
)
205 (+ (cdr mouse-avoidance-state
) deltay
)))
206 (if (or (eq mouse-avoidance-mode
'animate
)
207 (eq mouse-avoidance-mode
'proteus
))
209 (color (cdr (assoc 'mouse-color
(frame-parameters)))))
211 (mouse-avoidance-set-mouse-position
212 (cons (+ (car cur-pos
) (round (* i deltax
)))
213 (+ (cdr cur-pos
) (round (* i deltay
)))))
214 (setq i
(+ i
(max .1 (/ 1.0 mouse-avoidance-nudge-dist
))))
215 (if (eq mouse-avoidance-mode
'proteus
)
217 (setq x-pointer-shape
(mouse-avoidance-random-shape))
218 (set-mouse-color color
)))
219 (sit-for mouse-avoidance-animation-delay
)))
220 (mouse-avoidance-set-mouse-position (cons (+ (car (cdr cur
)) deltax
)
221 (+ (cdr (cdr cur
)) deltay
))))))
223 (defun mouse-avoidance-random-shape ()
224 "Return a random cursor shape.
225 This assumes that any variable whose name begins with x-pointer- and
226 has an integer value is a valid cursor shape. You might want to
227 redefine this function to suit your own tastes."
228 (if (null mouse-avoidance-pointer-shapes
)
230 (setq mouse-avoidance-pointer-shapes
231 (mapcar '(lambda (x) (symbol-value (intern x
)))
232 (all-completions "x-pointer-" obarray
235 (integerp (symbol-value x
)))))))
236 (setq mouse-avoidance-n-pointer-shapes
237 (length mouse-avoidance-pointer-shapes
))))
238 (nth (random mouse-avoidance-n-pointer-shapes
)
239 mouse-avoidance-pointer-shapes
))
241 (defun mouse-avoidance-banish-hook ()
242 (if (and (not executing-kbd-macro
) ; don't check inside macro
243 (mouse-avoidance-kbd-command (this-command-keys)))
244 (mouse-avoidance-banish-mouse)))
246 (defun mouse-avoidance-exile-hook ()
247 ;; For exile mode, the state is nil when the mouse is in its normal
248 ;; position, and set to the old mouse-position when the mouse is in exile.
249 (if (and (not executing-kbd-macro
)
250 (mouse-avoidance-kbd-command (this-command-keys)))
251 (let ((mp (mouse-position)))
252 (cond ((and (not mouse-avoidance-state
)
253 (mouse-avoidance-too-close-p mp
))
254 (setq mouse-avoidance-state mp
)
255 (mouse-avoidance-banish-mouse))
256 ((and mouse-avoidance-state
257 (not (mouse-avoidance-too-close-p mouse-avoidance-state
)))
258 (if (and (eq (car mp
) (selected-frame))
259 (equal (cdr mp
) (mouse-avoidance-banish-destination)))
260 (mouse-avoidance-set-mouse-position
261 ;; move back only if user has not moved mouse
262 (cdr mouse-avoidance-state
)))
263 ;; but clear state anyway, to be ready for another move
264 (setq mouse-avoidance-state nil
))))))
266 (defun mouse-avoidance-fancy-hook ()
267 ;; Used for the "fancy" modes, ie jump et al.
268 (if (and (not executing-kbd-macro
) ; don't check inside macro
269 (mouse-avoidance-kbd-command (this-command-keys))
270 (mouse-avoidance-too-close-p (mouse-position)))
271 (let ((old-pos (mouse-position)))
272 (mouse-avoidance-nudge-mouse)
273 (if (not (eq (selected-frame) (car old-pos
))) ; move went awry
274 (set-mouse-position old-pos
(car old-pos
) ; sigh..
276 (cdr (cdr old-pos
)))))))
278 (defun mouse-avoidance-kbd-command (key)
279 "Return t if the KEYSEQENCE is composed of keyboard events only.
280 Return nil if there are any lists in the key sequence."
281 (cond ((null key
) nil
) ; Null event seems to be
282 ; returned occasionally.
283 ((not (vectorp key
)) t
) ; Strings are keyboard events.
288 (if (listp (aref key i
))
293 (defun mouse-avoidance-mode (&optional mode
)
294 "Set cursor avoidance mode to MODE.
295 MODE should be one of the symbols `banish', `exile', `jump', `animate',
296 `cat-and-mouse', `proteus', or `none'.
298 If MODE is nil, toggle mouse avoidance between `none` and `banish'
299 modes. Positive numbers and symbols other than the above are treated
300 as equivalent to `banish'; negative numbers and `-' are equivalent to `none'.
302 Effects of the different modes:
303 * banish: Move the mouse to the upper-right corner on any keypress.
304 * exile: Move the mouse to the corner only if the cursor gets too close,
305 and allow it to return once the cursor is out of the way.
306 * jump: If the cursor gets too close to the mouse, displace the mouse
307 a random distance & direction.
308 * animate: As `jump', but shows steps along the way for illusion of motion.
309 * cat-and-mouse: Same as `animate'.
310 * proteus: As `animate', but changes the shape of the mouse pointer too.
312 Whenever the mouse is moved, the frame is also raised.
314 \(see `mouse-avoidance-threshold' for definition of \"too close\",
315 and `mouse-avoidance-nudge-dist' and `mouse-avoidance-nudge-var' for
316 definition of \"random distance\".)"
318 (list (intern (completing-read
319 "Select cursor avoidance technique (SPACE for list): "
320 '(("banish") ("exile") ("jump") ("animate")
321 ("cat-and-mouse") ("proteus") ("none"))
323 (if (eq mode
'cat-and-mouse
)
324 (setq mode
'animate
))
325 (setq post-command-hook
326 (delete 'mouse-avoidance-banish-hook
(append post-command-hook nil
)))
327 (setq post-command-hook
328 (delete 'mouse-avoidance-exile-hook
(append post-command-hook nil
)))
329 (setq post-command-hook
330 (delete 'mouse-avoidance-fancy-hook
(append post-command-hook nil
)))
331 (cond ((eq mode
'none
)
332 (setq mouse-avoidance-mode nil
))
336 (add-hook 'post-command-hook
'mouse-avoidance-fancy-hook
)
337 (setq mouse-avoidance-mode mode
338 mouse-avoidance-state
(cons 0 0)))
340 (add-hook 'post-command-hook
'mouse-avoidance-exile-hook
)
341 (setq mouse-avoidance-mode mode
342 mouse-avoidance-state nil
))
343 ((or (eq mode
'banish
)
345 (and (null mode
) (null mouse-avoidance-mode
))
346 (and mode
(> (prefix-numeric-value mode
) 0)))
347 (add-hook 'post-command-hook
'mouse-avoidance-banish-hook
)
348 (setq mouse-avoidance-mode
'banish
))
349 (t (setq mouse-avoidance-mode nil
)))
350 (force-mode-line-update))
352 (or (assq 'mouse-avoidance-mode minor-mode-alist
)
353 (setq minor-mode-alist
(cons '(mouse-avoidance-mode " Avoid")