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1 ;;; avoid.el --- make mouse pointer stay out of the way of editing
2
3 ;; Copyright (C) 1993, 1994, 2000, 2002, 2003, 2004,
4 ;; 2005, 2006 Free Software Foundation, Inc.
5
6 ;; Author: Boris Goldowsky <boris@gnu.org>
7 ;; Keywords: mouse
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 the
23 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
24 ;; Boston, MA 02110-1301, USA.
25
26 ;;; Commentary:
27
28 ;; For those who are annoyed by the mouse pointer obscuring text,
29 ;; this mode moves the mouse pointer - either just a little out of
30 ;; the way, or all the way to the corner of the frame.
31 ;; To use, load or evaluate this file and type M-x mouse-avoidance-mode .
32 ;; To set up permanently, put the following in your .emacs:
33 ;;
34 ;; (if (display-mouse-p) (mouse-avoidance-mode 'animate))
35 ;;
36 ;; Other legitimate alternatives include
37 ;; `banish', `exile', `jump', `cat-and-mouse', and `proteus'.
38 ;; They do somewhat different things.
39 ;; See the documentation for function `mouse-avoidance-mode' for
40 ;; details of the different modes.
41 ;;
42 ;; For added silliness, make the animatee animate...
43 ;; put something similar to the following into your .emacs:
44 ;;
45 ;; (if (eq window-system 'x)
46 ;; (mouse-avoidance-set-pointer-shape
47 ;; (eval (nth (random 4)
48 ;; '(x-pointer-man x-pointer-spider
49 ;; x-pointer-gobbler x-pointer-gumby)))))
50 ;;
51 ;; For completely random pointer shape, replace the setq above with:
52 ;; (setq x-pointer-shape (mouse-avoidance-random-shape))
53 ;;
54 ;; Bugs / Warnings / To-Do:
55 ;;
56 ;; - Using this code does slow Emacs down. "banish" mode shouldn't
57 ;; be too bad, and on my workstation even "animate" is reasonable.
58 ;;
59 ;; - It ought to find out where any overlapping frames are and avoid them,
60 ;; rather than always raising the frame.
61
62 ;; Credits:
63 ;; This code was helped by all those who contributed suggestions,
64 ;; fixes, and additions
65 ;; Joe Harrington (and his advisor), for the original inspiration.
66 ;; Ken Manheimer, for dreaming up the Protean mode.
67 ;; Richard Stallman, for the awful cat-and-mouse pun, among other things.
68 ;; Mike Williams, Denis Howe, Bill Benedetto, Chris Moore, Don Morris,
69 ;; Simon Marshall, and M.S. Ashton, for their feedback.
70
71 ;;; Code:
72
73 (provide 'avoid)
74
75 (defgroup avoid nil
76 "Make mouse pointer stay out of the way of editing."
77 :prefix "mouse-avoidance-"
78 :group 'mouse)
79
80 ;;;###autoload
81 (defcustom mouse-avoidance-mode nil
82 "Activate mouse avoidance mode.
83 See function `mouse-avoidance-mode' for possible values.
84 Setting this variable directly does not take effect;
85 use either \\[customize] or the function `mouse-avoidance-mode'."
86 :set (lambda (symbol value)
87 ;; 'none below prevents toggling when value is nil.
88 (mouse-avoidance-mode (or value 'none)))
89 :initialize 'custom-initialize-default
90 :type '(choice (const :tag "none" nil) (const banish) (const jump)
91 (const animate) (const exile) (const proteus)
92 )
93 :group 'avoid
94 :require 'avoid
95 :version "20.3")
96
97
98 (defcustom mouse-avoidance-nudge-dist 15
99 "*Average distance that mouse will be moved when approached by cursor.
100 Only applies in Mouse-Avoidance mode `jump' and its derivatives.
101 For best results make this larger than `mouse-avoidance-threshold'."
102 :type 'integer
103 :group 'avoid)
104
105 (defcustom mouse-avoidance-nudge-var 10
106 "*Variability of `mouse-avoidance-nudge-dist' (which see)."
107 :type 'integer
108 :group 'avoid)
109
110 (defcustom mouse-avoidance-animation-delay .01
111 "Delay between animation steps, in seconds."
112 :type 'number
113 :group 'avoid)
114
115 (defcustom mouse-avoidance-threshold 5
116 "*Mouse-pointer's flight distance.
117 If the cursor gets closer than this, the mouse pointer will move away.
118 Only applies in mouse-avoidance-modes `animate' and `jump'."
119 :type 'integer
120 :group 'avoid)
121
122 ;; Internal variables
123 (defvar mouse-avoidance-state nil)
124 (defvar mouse-avoidance-pointer-shapes nil)
125 (defvar mouse-avoidance-n-pointer-shapes 0)
126 (defvar mouse-avoidance-old-pointer-shape nil)
127
128 ;; This timer is used to run something when Emacs is idle.
129 (defvar mouse-avoidance-timer nil)
130
131 ;;; Functions:
132
133 (defsubst mouse-avoidance-set-pointer-shape (shape)
134 "Set the shape of the mouse pointer to SHAPE."
135 (when (boundp 'x-pointer-shape)
136 (setq x-pointer-shape shape)
137 (set-mouse-color nil)))
138
139 (defun mouse-avoidance-point-position ()
140 "Return the position of point as (FRAME X . Y).
141 Analogous to `mouse-position'."
142 (let ((edges (window-inside-edges))
143 (x-y (posn-x-y (posn-at-point))))
144 (cons (selected-frame)
145 (cons (+ (car edges)
146 (/ (car x-y) (frame-char-width)))
147 (+ (car (cdr edges))
148 (/ (cdr x-y) (frame-char-height)))))))
149
150 ;(defun mouse-avoidance-point-position-test ()
151 ; (interactive)
152 ; (message (format "point=%s mouse=%s"
153 ; (cdr (mouse-avoidance-point-position))
154 ; (cdr (mouse-position)))))
155
156 (defun mouse-avoidance-set-mouse-position (pos)
157 ;; Carefully set mouse position to given position (X . Y)
158 ;; Ideally, should check if X,Y is in the current frame, and if not,
159 ;; leave the mouse where it was. However, this is currently
160 ;; difficult to do, so we just raise the frame to avoid frame switches.
161 ;; Returns t if it moved the mouse.
162 (let ((f (selected-frame)))
163 (raise-frame f)
164 (set-mouse-position f (car pos) (cdr pos))
165 t))
166
167 (defun mouse-avoidance-too-close-p (mouse)
168 "Return t if mouse pointer and point cursor are too close.
169 MOUSE is the current mouse position as returned by `mouse-position'.
170 Acceptable distance is defined by `mouse-avoidance-threshold'."
171 (let* ((frame (car mouse))
172 (mouse-y (cdr (cdr mouse)))
173 (tool-bar-lines (frame-parameter nil 'tool-bar-lines)))
174 (or tool-bar-lines
175 (setq tool-bar-lines 0))
176 (if (and mouse-y (< mouse-y tool-bar-lines))
177 nil
178 (let ((point (mouse-avoidance-point-position))
179 (mouse-x (car (cdr mouse))))
180 (and (eq frame (car point))
181 (not (null mouse-x))
182 (< (abs (- mouse-x (car (cdr point))))
183 mouse-avoidance-threshold)
184 (< (abs (- mouse-y (cdr (cdr point))))
185 mouse-avoidance-threshold))))))
186
187 (defun mouse-avoidance-banish-destination ()
188 "The position to which Mouse-Avoidance mode `banish' moves the mouse.
189 You can redefine this if you want the mouse banished to a different corner."
190 (let* ((pos (window-edges)))
191 (cons (- (nth 2 pos) 2)
192 (nth 1 pos))))
193
194 (defun mouse-avoidance-banish-mouse ()
195 ;; Put the mouse pointer in the upper-right corner of the current frame.
196 (mouse-avoidance-set-mouse-position (mouse-avoidance-banish-destination)))
197
198 (defsubst mouse-avoidance-delta (cur delta dist var min max)
199 ;; Decide how far to move in either dimension.
200 ;; Args are the CURRENT location, the desired DELTA for
201 ;; warp-conservation, the DISTANCE we like to move, the VARIABILITY
202 ;; in distance allowed, and the MIN and MAX possible window positions.
203 ;; Returns something as close to DELTA as possible within the constraints.
204 (let ((L1 (max (- min cur) (+ (- dist) (- var))))
205 (R1 (+ (- dist) var ))
206 (L2 (+ dist (- var)))
207 (R2 (min (- max cur) (+ dist var))))
208 (if (< R1 (- min cur)) (setq L1 nil R1 nil))
209 (if (> L2 (- max cur)) (setq L2 nil R2 nil))
210 (cond ((and L1 (< delta L1)) L1)
211 ((and R1 (< delta R1)) delta)
212 ((and R1 (< delta 0)) R1)
213 ((and L2 (< delta L2)) L2)
214 ((and R2 (< delta R2)) delta)
215 (R2)
216 ((or R1 L2))
217 (t 0))))
218
219 (defun mouse-avoidance-nudge-mouse ()
220 ;; Push the mouse a little way away, possibly animating the move.
221 ;; For these modes, state keeps track of the total offset that we've
222 ;; accumulated, and tries to keep it close to zero.
223 (let* ((cur (mouse-position))
224 (cur-frame (car cur))
225 (cur-pos (cdr cur))
226 (pos (window-edges))
227 (wleft (pop pos))
228 (wtop (pop pos))
229 (wright (pop pos))
230 (wbot (pop pos))
231 (deltax (mouse-avoidance-delta
232 (car cur-pos) (- (random mouse-avoidance-nudge-var)
233 (car mouse-avoidance-state))
234 mouse-avoidance-nudge-dist mouse-avoidance-nudge-var
235 wleft (1- wright)))
236 (deltay (mouse-avoidance-delta
237 (cdr cur-pos) (- (random mouse-avoidance-nudge-var)
238 (cdr mouse-avoidance-state))
239 mouse-avoidance-nudge-dist mouse-avoidance-nudge-var
240 wtop (1- wbot))))
241 (setq mouse-avoidance-state
242 (cons (+ (car mouse-avoidance-state) deltax)
243 (+ (cdr mouse-avoidance-state) deltay)))
244 (if (or (eq mouse-avoidance-mode 'animate)
245 (eq mouse-avoidance-mode 'proteus))
246 (let ((i 0.0))
247 (while (<= i 1)
248 (mouse-avoidance-set-mouse-position
249 (cons (+ (car cur-pos) (round (* i deltax)))
250 (+ (cdr cur-pos) (round (* i deltay)))))
251 (setq i (+ i (max .1 (/ 1.0 mouse-avoidance-nudge-dist))))
252 (if (eq mouse-avoidance-mode 'proteus)
253 (mouse-avoidance-set-pointer-shape
254 (mouse-avoidance-random-shape)))
255 (sit-for mouse-avoidance-animation-delay)))
256 (mouse-avoidance-set-mouse-position (cons (+ (car (cdr cur)) deltax)
257 (+ (cdr (cdr cur)) deltay))))))
258
259 (defun mouse-avoidance-random-shape ()
260 "Return a random cursor shape.
261 This assumes that any variable whose name begins with x-pointer- and
262 has an integer value is a valid cursor shape. You might want to
263 redefine this function to suit your own tastes."
264 (if (null mouse-avoidance-pointer-shapes)
265 (progn
266 (setq mouse-avoidance-pointer-shapes
267 (mapcar (lambda (x) (symbol-value (intern x)))
268 (all-completions "x-pointer-" obarray
269 (lambda (x)
270 (and (boundp x)
271 (integerp (symbol-value x)))))))
272 (setq mouse-avoidance-n-pointer-shapes
273 (length mouse-avoidance-pointer-shapes))))
274 (nth (random mouse-avoidance-n-pointer-shapes)
275 mouse-avoidance-pointer-shapes))
276
277 (defun mouse-avoidance-ignore-p ()
278 (let ((mp (mouse-position)))
279 (or executing-kbd-macro ; don't check inside macro
280 (null (cadr mp)) ; don't move unless in an Emacs frame
281 (not (eq (car mp) (selected-frame)))
282 ;; Don't do anything if last event was a mouse event.
283 ;; FIXME: this code fails in the case where the mouse was moved
284 ;; since the last key-press but without generating any event.
285 (and (consp last-input-event)
286 (symbolp (car last-input-event))
287 (let ((modifiers (event-modifiers (car last-input-event))))
288 (or (memq (car last-input-event)
289 '(mouse-movement scroll-bar-movement
290 select-window switch-frame))
291 (memq 'click modifiers)
292 (memq 'double modifiers)
293 (memq 'triple modifiers)
294 (memq 'drag modifiers)
295 (memq 'down modifiers)))))))
296
297 (defun mouse-avoidance-banish-hook ()
298 (if (not (mouse-avoidance-ignore-p))
299 (mouse-avoidance-banish-mouse)))
300
301 (defun mouse-avoidance-exile-hook ()
302 ;; For exile mode, the state is nil when the mouse is in its normal
303 ;; position, and set to the old mouse-position when the mouse is in exile.
304 (if (not (mouse-avoidance-ignore-p))
305 (let ((mp (mouse-position)))
306 (cond ((and (not mouse-avoidance-state)
307 (mouse-avoidance-too-close-p mp))
308 (setq mouse-avoidance-state mp)
309 (mouse-avoidance-banish-mouse))
310 ((and mouse-avoidance-state
311 (not (mouse-avoidance-too-close-p mouse-avoidance-state)))
312 (if (and (eq (car mp) (selected-frame))
313 (equal (cdr mp) (mouse-avoidance-banish-destination)))
314 (mouse-avoidance-set-mouse-position
315 ;; move back only if user has not moved mouse
316 (cdr mouse-avoidance-state)))
317 ;; but clear state anyway, to be ready for another move
318 (setq mouse-avoidance-state nil))))))
319
320 (defun mouse-avoidance-fancy-hook ()
321 ;; Used for the "fancy" modes, ie jump et al.
322 (if (and (not (mouse-avoidance-ignore-p))
323 (mouse-avoidance-too-close-p (mouse-position)))
324 (let ((old-pos (mouse-position)))
325 (mouse-avoidance-nudge-mouse)
326 (if (not (eq (selected-frame) (car old-pos)))
327 ;; This should never happen.
328 (apply 'set-mouse-position old-pos)))))
329
330 ;;;###autoload
331 (defun mouse-avoidance-mode (&optional mode)
332 "Set cursor avoidance mode to MODE.
333 MODE should be one of the symbols `banish', `exile', `jump', `animate',
334 `cat-and-mouse', `proteus', or `none'.
335
336 If MODE is nil, toggle mouse avoidance between `none' and `banish'
337 modes. Positive numbers and symbols other than the above are treated
338 as equivalent to `banish'; negative numbers and `-' are equivalent to `none'.
339
340 Effects of the different modes:
341 * banish: Move the mouse to the upper-right corner on any keypress.
342 * exile: Move the mouse to the corner only if the cursor gets too close,
343 and allow it to return once the cursor is out of the way.
344 * jump: If the cursor gets too close to the mouse, displace the mouse
345 a random distance & direction.
346 * animate: As `jump', but shows steps along the way for illusion of motion.
347 * cat-and-mouse: Same as `animate'.
348 * proteus: As `animate', but changes the shape of the mouse pointer too.
349
350 Whenever the mouse is moved, the frame is also raised.
351
352 \(see `mouse-avoidance-threshold' for definition of \"too close\",
353 and `mouse-avoidance-nudge-dist' and `mouse-avoidance-nudge-var' for
354 definition of \"random distance\".)"
355 (interactive
356 (list (intern (completing-read
357 "Select cursor avoidance technique (SPACE for list): "
358 '(("banish") ("exile") ("jump") ("animate")
359 ("cat-and-mouse") ("proteus") ("none"))
360 nil t))))
361 (if (eq mode 'cat-and-mouse)
362 (setq mode 'animate))
363 (if mouse-avoidance-timer
364 (cancel-timer mouse-avoidance-timer))
365 (setq mouse-avoidance-timer nil)
366
367 ;; Restore pointer shape if necessary
368 (if (eq mouse-avoidance-mode 'proteus)
369 (mouse-avoidance-set-pointer-shape mouse-avoidance-old-pointer-shape))
370
371 ;; Do additional setup depending on version of mode requested
372 (cond ((eq mode 'none)
373 (setq mouse-avoidance-mode nil))
374 ((or (eq mode 'jump)
375 (eq mode 'animate)
376 (eq mode 'proteus))
377 (setq mouse-avoidance-timer
378 (run-with-idle-timer 0.1 t 'mouse-avoidance-fancy-hook))
379 (setq mouse-avoidance-mode mode
380 mouse-avoidance-state (cons 0 0)
381 mouse-avoidance-old-pointer-shape
382 (and (boundp 'x-pointer-shape) x-pointer-shape)))
383 ((eq mode 'exile)
384 (setq mouse-avoidance-timer
385 (run-with-idle-timer 0.1 t 'mouse-avoidance-exile-hook))
386 (setq mouse-avoidance-mode mode
387 mouse-avoidance-state nil))
388 ((or (eq mode 'banish)
389 (eq mode t)
390 (and (null mode) (null mouse-avoidance-mode))
391 (and mode (> (prefix-numeric-value mode) 0)))
392 (setq mouse-avoidance-timer
393 (run-with-idle-timer 0.1 t 'mouse-avoidance-banish-hook))
394 (setq mouse-avoidance-mode 'banish))
395 (t (setq mouse-avoidance-mode nil)))
396 (force-mode-line-update))
397
398 ;; Most people who use avoid mode leave it on all the time, so it's not
399 ;; very informative to announce it in the mode line.
400 ;;(or (assq 'mouse-avoidance-mode minor-mode-alist)
401 ;; (setq minor-mode-alist (cons '(mouse-avoidance-mode " Avoid")
402 ;; minor-mode-alist)))
403
404 ;; Needed for custom.
405 (if mouse-avoidance-mode
406 (mouse-avoidance-mode mouse-avoidance-mode))
407
408 ;; arch-tag: 64ad4ef8-a870-4183-8d96-3aa93b7a6800
409 ;;; avoid.el ends here