Skip to content


Subversion checkout URL

You can clone with
Download ZIP
branch: master
Fetching contributors…

Cannot retrieve contributors at this time

413 lines (367 sloc) 15.656 kb
;;; avoid.el --- make mouse pointer stay out of the way of editing
;; Copyright (C) 1993, 1994, 2000, 2001, 2002, 2003, 2004,
;; 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
;; Author: Boris Goldowsky <>
;; Keywords: mouse
;; 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 3 of the License, 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
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs. If not, see <>.
;;; 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 the following in your .emacs:
;; (if (display-mouse-p) (mouse-avoidance-mode 'animate))
;; Other legitimate alternatives include
;; `banish', `exile', `jump', `cat-and-mouse', and `proteus'.
;; They do somewhat different things.
;; 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:
;; (if (eq window-system 'x)
;; (mouse-avoidance-set-pointer-shape
;; (eval (nth (random 4)
;; '(x-pointer-man x-pointer-spider
;; x-pointer-gobbler x-pointer-gumby)))))
;; For completely random pointer shape, replace the setq above with:
;; (setq x-pointer-shape (mouse-avoidance-random-shape))
;; Bugs / Warnings / To-Do:
;; - Using this code does slow Emacs down. "banish" mode shouldn't
;; be too bad, and on my workstation even "animate" is reasonable.
;; - It ought to find out where any overlapping frames are and avoid them,
;; rather than always raising the frame.
;; 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)
(defgroup avoid nil
"Make mouse pointer stay out of the way of editing."
:prefix "mouse-avoidance-"
:group 'mouse)
(defcustom mouse-avoidance-mode nil
"Activate mouse avoidance mode.
See function `mouse-avoidance-mode' for possible values.
Setting this variable directly does not take effect;
use either \\[customize] or the function `mouse-avoidance-mode'."
:set (lambda (symbol value)
;; 'none below prevents toggling when value is nil.
(mouse-avoidance-mode (or value 'none)))
:initialize 'custom-initialize-default
:type '(choice (const :tag "none" nil) (const banish) (const jump)
(const animate) (const exile) (const proteus)
:group 'avoid
:require 'avoid
:version "20.3")
(defcustom mouse-avoidance-nudge-dist 15
"Average distance that mouse will be moved when approached by cursor.
Only applies in Mouse-Avoidance mode `jump' and its derivatives.
For best results make this larger than `mouse-avoidance-threshold'."
:type 'integer
:group 'avoid)
(defcustom mouse-avoidance-nudge-var 10
"Variability of `mouse-avoidance-nudge-dist' (which see)."
:type 'integer
:group 'avoid)
(defcustom mouse-avoidance-animation-delay .01
"Delay between animation steps, in seconds."
:type 'number
:group 'avoid)
(defcustom mouse-avoidance-threshold 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'."
:type 'integer
:group 'avoid)
;; Internal variables
(defvar mouse-avoidance-state nil)
(defvar mouse-avoidance-pointer-shapes nil)
(defvar mouse-avoidance-n-pointer-shapes 0)
(defvar mouse-avoidance-old-pointer-shape nil)
(defvar mouse-avoidance-animating-pointer nil)
;; This timer is used to run something when Emacs is idle.
(defvar mouse-avoidance-timer nil)
;;; Functions:
(defsubst mouse-avoidance-set-pointer-shape (shape)
"Set the shape of the mouse pointer to SHAPE."
(when (boundp 'x-pointer-shape)
(setq x-pointer-shape shape)
(set-mouse-color nil)))
(defun mouse-avoidance-point-position ()
"Return the position of point as (FRAME X . Y).
Analogous to `mouse-position'."
(let ((edges (window-inside-edges))
(x-y (posn-x-y (posn-at-point))))
(cons (selected-frame)
(cons (+ (car edges)
(/ (car x-y) (frame-char-width)))
(+ (car (cdr edges))
(/ (cdr x-y) (frame-char-height)))))))
;(defun mouse-avoidance-point-position-test ()
; (interactive)
; (message (format "point=%s mouse=%s"
; (cdr (mouse-avoidance-point-position))
; (cdr (mouse-position)))))
(defun mouse-avoidance-set-mouse-position (pos)
;; Carefully set mouse position to given position (X . Y)
;; Ideally, should check if X,Y is in the current frame, and if not,
;; leave the mouse where it was. However, this is currently
;; difficult to do, so we just raise the frame to avoid frame switches.
;; Returns t if it moved the mouse.
(let ((f (selected-frame)))
(raise-frame f)
(set-mouse-position f (car pos) (cdr pos))
(defun mouse-avoidance-too-close-p (mouse)
"Return t if mouse pointer and point cursor are too close.
MOUSE is the current mouse position as returned by `mouse-position'.
Acceptable distance is defined by `mouse-avoidance-threshold'."
(let* ((frame (car mouse))
(mouse-y (cdr (cdr mouse)))
(tool-bar-lines (frame-parameter nil 'tool-bar-lines)))
(or tool-bar-lines
(setq tool-bar-lines 0))
(if (and mouse-y (< mouse-y tool-bar-lines))
(let ((point (mouse-avoidance-point-position))
(mouse-x (car (cdr mouse))))
(and (eq frame (car point))
(not (null mouse-x))
(< (abs (- mouse-x (car (cdr point))))
(< (abs (- mouse-y (cdr (cdr point))))
(defun mouse-avoidance-banish-destination ()
"The position to which Mouse-Avoidance mode `banish' moves the mouse.
You can redefine this if you want the mouse banished to a different corner."
(let* ((pos (window-edges)))
(cons (- (nth 2 pos) 2)
(nth 1 pos))))
(defun mouse-avoidance-banish-mouse ()
;; Put the mouse pointer in the upper-right corner of the current frame.
(mouse-avoidance-set-mouse-position (mouse-avoidance-banish-destination)))
(defsubst mouse-avoidance-delta (cur delta dist var min max)
;; Decide how far to move in either dimension.
;; Args are the CURRENT location, the desired DELTA for
;; warp-conservation, the DISTANCE we like to move, the VARIABILITY
;; in distance allowed, and the MIN and MAX possible window positions.
;; Returns something as close to DELTA as possible within the constraints.
(let ((L1 (max (- min cur) (+ (- dist) (- var))))
(R1 (+ (- dist) var ))
(L2 (+ dist (- var)))
(R2 (min (- max cur) (+ dist var))))
(if (< R1 (- min cur)) (setq L1 nil R1 nil))
(if (> L2 (- max cur)) (setq L2 nil R2 nil))
(cond ((and L1 (< delta L1)) L1)
((and R1 (< delta R1)) delta)
((and R1 (< delta 0)) R1)
((and L2 (< delta L2)) L2)
((and R2 (< delta R2)) delta)
((or R1 L2))
(t 0))))
(defun mouse-avoidance-nudge-mouse ()
;; Push the mouse a little way away, possibly animating the move.
;; For these modes, state keeps track of the total offset that we've
;; accumulated, and tries to keep it close to zero.
(let* ((cur (mouse-position))
(cur-frame (car cur))
(cur-pos (cdr cur))
(pos (window-edges))
(wleft (pop pos))
(wtop (pop pos))
(wright (pop pos))
(wbot (pop pos))
(deltax (mouse-avoidance-delta
(car cur-pos) (- (random mouse-avoidance-nudge-var)
(car mouse-avoidance-state))
mouse-avoidance-nudge-dist mouse-avoidance-nudge-var
wleft (1- wright)))
(deltay (mouse-avoidance-delta
(cdr cur-pos) (- (random mouse-avoidance-nudge-var)
(cdr mouse-avoidance-state))
mouse-avoidance-nudge-dist mouse-avoidance-nudge-var
wtop (1- wbot))))
(setq mouse-avoidance-state
(cons (+ (car mouse-avoidance-state) deltax)
(+ (cdr mouse-avoidance-state) deltay)))
(if (or (eq mouse-avoidance-mode 'animate)
(eq mouse-avoidance-mode 'proteus))
(let ((i 0.0)
(incr (max .1 (/ 1.0 mouse-avoidance-nudge-dist))))
(setq mouse-avoidance-animating-pointer t)
(while (<= i 1)
(cons (+ (car cur-pos) (round (* i deltax)))
(+ (cdr cur-pos) (round (* i deltay)))))
(setq i (+ i incr))
(if (eq mouse-avoidance-mode 'proteus)
(sit-for mouse-avoidance-animation-delay))
(setq mouse-avoidance-animating-pointer nil))
(mouse-avoidance-set-mouse-position (cons (+ (car (cdr cur)) deltax)
(+ (cdr (cdr cur)) deltay))))))
(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)
(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)
(defun mouse-avoidance-ignore-p ()
(let ((mp (mouse-position)))
(or executing-kbd-macro ; don't check inside macro
(null (cadr mp)) ; don't move unless in an Emacs frame
(not (eq (car mp) (selected-frame)))
;; Don't do anything if last event was a mouse event.
;; FIXME: this code fails in the case where the mouse was moved
;; since the last key-press but without generating any event.
(and (consp last-input-event)
(symbolp (car last-input-event))
(let ((modifiers (event-modifiers (car last-input-event))))
(or (memq (car last-input-event)
'(mouse-movement scroll-bar-movement
select-window switch-frame))
(memq 'click modifiers)
(memq 'double modifiers)
(memq 'triple modifiers)
(memq 'drag modifiers)
(memq 'down modifiers)))))))
(defun mouse-avoidance-banish ()
(if (not (mouse-avoidance-ignore-p))
(defun mouse-avoidance-exile ()
;; For exile mode, the state is nil when the mouse is in its normal
;; position, and set to the old mouse-position when the mouse is in exile.
(if (not (mouse-avoidance-ignore-p))
(let ((mp (mouse-position)))
(cond ((and (not mouse-avoidance-state)
(mouse-avoidance-too-close-p mp))
(setq mouse-avoidance-state mp)
((and mouse-avoidance-state
(not (mouse-avoidance-too-close-p mouse-avoidance-state)))
(if (and (eq (car mp) (selected-frame))
(equal (cdr mp) (mouse-avoidance-banish-destination)))
;; move back only if user has not moved mouse
(cdr mouse-avoidance-state)))
;; but clear state anyway, to be ready for another move
(setq mouse-avoidance-state nil))))))
(defun mouse-avoidance-fancy ()
;; Used for the "fancy" modes, ie jump et al.
(if (and (not mouse-avoidance-animating-pointer)
(not (mouse-avoidance-ignore-p))
(mouse-avoidance-too-close-p (mouse-position)))
(let ((old-pos (mouse-position)))
(if (not (eq (selected-frame) (car old-pos)))
;; This should never happen.
(apply 'set-mouse-position old-pos)))))
(defun mouse-avoidance-mode (&optional mode)
"Set cursor avoidance mode to MODE.
MODE should be one of the symbols `banish', `exile', `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.
* exile: Move the mouse to the corner only if the cursor gets too close,
and allow it to return once the cursor is out of the way.
* jump: If the cursor gets too close to the mouse, displace the mouse
a random distance & direction.
* 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.
Whenever the mouse is moved, the frame is also raised.
\(see `mouse-avoidance-threshold' for definition of \"too close\",
and `mouse-avoidance-nudge-dist' and `mouse-avoidance-nudge-var' for
definition of \"random distance\".)"
(list (intern (completing-read
"Select cursor avoidance technique (SPACE for list): "
'(("banish") ("exile") ("jump") ("animate")
("cat-and-mouse") ("proteus") ("none"))
nil t))))
(if (eq mode 'cat-and-mouse)
(setq mode 'animate))
(if mouse-avoidance-timer
(cancel-timer mouse-avoidance-timer))
(setq mouse-avoidance-timer nil)
;; Restore pointer shape if necessary
(if (eq mouse-avoidance-mode 'proteus)
(mouse-avoidance-set-pointer-shape mouse-avoidance-old-pointer-shape))
;; Do additional setup depending on version of mode requested
(cond ((eq mode 'none)
(setq mouse-avoidance-mode nil))
((or (eq mode 'jump)
(eq mode 'animate)
(eq mode 'proteus))
(setq mouse-avoidance-timer
(run-with-idle-timer 0.1 t 'mouse-avoidance-fancy))
(setq mouse-avoidance-mode mode
mouse-avoidance-state (cons 0 0)
(and (boundp 'x-pointer-shape) x-pointer-shape)))
((eq mode 'exile)
(setq mouse-avoidance-timer
(run-with-idle-timer 0.1 t 'mouse-avoidance-exile))
(setq mouse-avoidance-mode mode
mouse-avoidance-state nil))
((or (eq mode 'banish)
(eq mode t)
(and (null mode) (null mouse-avoidance-mode))
(and mode (> (prefix-numeric-value mode) 0)))
(setq mouse-avoidance-timer
(run-with-idle-timer 0.1 t 'mouse-avoidance-banish))
(setq mouse-avoidance-mode 'banish))
(t (setq mouse-avoidance-mode nil)))
;; Most people who use avoid mode leave it on all the time, so it's not
;; very informative to announce it in the mode line.
;;(or (assq 'mouse-avoidance-mode minor-mode-alist)
;; (setq minor-mode-alist (cons '(mouse-avoidance-mode " Avoid")
;; minor-mode-alist)))
;; Needed for custom.
(if mouse-avoidance-mode
(mouse-avoidance-mode mouse-avoidance-mode))
;; arch-tag: 64ad4ef8-a870-4183-8d96-3aa93b7a6800
;;; avoid.el ends here
Jump to Line
Something went wrong with that request. Please try again.