| 12
 3
 4
 5
 6
 7
 8
 9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
 100
 101
 102
 103
 104
 105
 106
 107
 108
 109
 110
 111
 112
 113
 114
 115
 116
 117
 118
 119
 120
 121
 122
 123
 124
 125
 126
 127
 128
 129
 130
 131
 132
 133
 134
 135
 136
 137
 138
 139
 140
 141
 142
 143
 144
 145
 146
 147
 148
 149
 150
 151
 152
 153
 154
 155
 156
 157
 158
 159
 160
 161
 162
 163
 164
 165
 166
 167
 168
 169
 170
 171
 172
 173
 174
 175
 176
 177
 178
 179
 180
 181
 182
 183
 184
 185
 186
 187
 188
 189
 190
 191
 192
 193
 194
 195
 196
 197
 198
 199
 200
 201
 202
 203
 204
 205
 206
 207
 208
 209
 210
 211
 212
 213
 214
 215
 216
 217
 218
 219
 220
 221
 222
 223
 224
 225
 226
 227
 228
 229
 230
 231
 232
 233
 234
 235
 236
 237
 238
 239
 240
 241
 242
 243
 244
 245
 246
 247
 248
 249
 250
 251
 252
 253
 254
 255
 256
 257
 258
 259
 260
 261
 262
 263
 264
 265
 266
 267
 268
 269
 270
 271
 272
 273
 274
 275
 276
 277
 278
 279
 280
 281
 282
 283
 284
 285
 
 | ;;; mwheel.el --- Wheel mouse support
;; Copyright (C) 1998, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
;;   2008, 2009, 2010, 2011, 2012  Free Software Foundation, Inc.
;; Maintainer: William M. Perry <wmperry@gnu.org>
;; 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
;; 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.  If not, see <http://www.gnu.org/licenses/>.
;;; Commentary:
;; This code will enable the use of the infamous 'wheel' on the new
;; crop of mice.  Under XFree86 and the XSuSE X Servers, the wheel
;; events are sent as button4/button5 events.
;; I for one would prefer some way of converting the button4/button5
;; events into different event types, like 'mwheel-up' or
;; 'mwheel-down', but I cannot find a way to do this very easily (or
;; portably), so for now I just live with it.
;; To enable this code, simply put this at the top of your .emacs
;; file:
;;
;; (mouse-wheel-mode 1)
;;; Code:
(require 'custom)
(require 'timer)
(defvar mouse-wheel-mode)
;; Setter function for mouse-button user-options.  Switch Mouse Wheel
;; mode off and on again so that the old button is unbound and
;; new button is bound to mwheel-scroll.
(defun mouse-wheel-change-button (var button)
  (set-default var button)
  ;; Sync the bindings.
  (when (bound-and-true-p mouse-wheel-mode) (mouse-wheel-mode 1)))
(defvar mouse-wheel-down-button 4)
(make-obsolete-variable 'mouse-wheel-down-button
                        'mouse-wheel-down-event
			"22.1")
(defcustom mouse-wheel-down-event
  (if (or (featurep 'w32-win) (featurep 'ns-win))
      'wheel-up
    (intern (format "mouse-%s" mouse-wheel-down-button)))
  "Event used for scrolling down."
  :group 'mouse
  :type 'symbol
  :set 'mouse-wheel-change-button)
(defvar mouse-wheel-up-button 5)
(make-obsolete-variable 'mouse-wheel-up-button
                        'mouse-wheel-up-event
			"22.1")
(defcustom mouse-wheel-up-event
  (if (or (featurep 'w32-win) (featurep 'ns-win))
      'wheel-down
    (intern (format "mouse-%s" mouse-wheel-up-button)))
  "Event used for scrolling up."
  :group 'mouse
  :type 'symbol
  :set 'mouse-wheel-change-button)
(defvar mouse-wheel-click-button 2)
(make-obsolete-variable 'mouse-wheel-click-button
                        'mouse-wheel-click-event
			"22.1")
(defcustom mouse-wheel-click-event
  (intern (format "mouse-%s" mouse-wheel-click-button))
  "Event that should be temporarily inhibited after mouse scrolling.
The mouse wheel is typically on the mouse-2 button, so it may easily
happen that text is accidentally yanked into the buffer when
scrolling with the mouse wheel.  To prevent that, this variable can be
set to the event sent when clicking on the mouse wheel button."
  :group 'mouse
  :type 'symbol
  :set 'mouse-wheel-change-button)
(defcustom mouse-wheel-inhibit-click-time 0.35
  "Time in seconds to inhibit clicking on mouse wheel button after scroll."
  :group 'mouse
  :type 'number)
(defcustom mouse-wheel-scroll-amount '(5 ((shift) . 1) ((control) . nil))
  "Amount to scroll windows by when spinning the mouse wheel.
This is an alist mapping the modifier key to the amount to scroll when
the wheel is moved with the modifier key depressed.
Elements of the list have the form (MODIFIERS . AMOUNT) or just AMOUNT if
MODIFIERS is nil.
AMOUNT should be the number of lines to scroll, or nil for near full
screen.  It can also be a floating point number, specifying the fraction of
a full screen to scroll.  A near full screen is `next-screen-context-lines'
less than a full screen."
  :group 'mouse
  :type '(cons
	  (choice :tag "Normal"
		  (const :tag "Full screen" :value nil)
		  (integer :tag "Specific # of lines")
		  (float :tag "Fraction of window")
		  (cons
		   (repeat (choice :tag "modifier"
				   (const alt) (const control) (const hyper)
				   (const meta) (const shift) (const super)))
		   (choice :tag "scroll amount"
			   (const :tag "Full screen" :value nil)
			   (integer :tag "Specific # of lines")
			   (float :tag "Fraction of window"))))
          (repeat
           (cons
            (repeat (choice :tag "modifier"
			    (const alt) (const control) (const hyper)
                            (const meta) (const shift) (const super)))
            (choice :tag "scroll amount"
                    (const :tag "Full screen" :value nil)
                    (integer :tag "Specific # of lines")
                    (float :tag "Fraction of window")))))
  :set 'mouse-wheel-change-button)
(defcustom mouse-wheel-progressive-speed t
  "If non-nil, the faster the user moves the wheel, the faster the scrolling.
Note that this has no effect when `mouse-wheel-scroll-amount' specifies
a \"near full screen\" scroll or when the mouse wheel sends key instead
of button events."
  :group 'mouse
  :type 'boolean)
(defcustom mouse-wheel-follow-mouse t
  "Whether the mouse wheel should scroll the window that the mouse is over.
This can be slightly disconcerting, but some people prefer it."
  :group 'mouse
  :type 'boolean)
(eval-and-compile
  (if (fboundp 'event-button)
      (fset 'mwheel-event-button 'event-button)
    (defun mwheel-event-button (event)
      (let ((x (event-basic-type event)))
	;; Map mouse-wheel events to appropriate buttons
	(if (eq 'mouse-wheel x)
	    (let ((amount (car (cdr (cdr (cdr event))))))
	      (if (< amount 0)
		  mouse-wheel-up-event
		mouse-wheel-down-event))
	  x))))
  (if (fboundp 'event-window)
      (fset 'mwheel-event-window 'event-window)
    (defun mwheel-event-window (event)
      (posn-window (event-start event)))))
(defvar mwheel-inhibit-click-event-timer nil
  "Timer running while mouse wheel click event is inhibited.")
(defun mwheel-inhibit-click-timeout ()
  "Handler for `mwheel-inhibit-click-event-timer'."
  (setq mwheel-inhibit-click-event-timer nil)
  (remove-hook 'pre-command-hook 'mwheel-filter-click-events))
(defun mwheel-filter-click-events ()
  "Discard `mouse-wheel-click-event' while scrolling the mouse."
  (if (eq (event-basic-type last-input-event) mouse-wheel-click-event)
      (setq this-command 'ignore)))
(defvar mwheel-scroll-up-function 'scroll-up
  "Function that does the job of scrolling upward.")
(defvar mwheel-scroll-down-function 'scroll-down
  "Function that does the job of scrolling downward.")
(defun mwheel-scroll (event)
  "Scroll up or down according to the EVENT.
This should only be bound to mouse buttons 4 and 5."
  (interactive (list last-input-event))
  (let* ((curwin (if mouse-wheel-follow-mouse
                     (prog1
                         (selected-window)
                       (select-window (mwheel-event-window event)))))
	 (buffer (window-buffer curwin))
	 (opoint (with-current-buffer buffer
		   (when (eq (car-safe transient-mark-mode) 'only)
		     (point))))
         (mods
	  (delq 'click (delq 'double (delq 'triple (event-modifiers event)))))
         (amt (assoc mods mouse-wheel-scroll-amount)))
    ;; Extract the actual amount or find the element that has no modifiers.
    (if amt (setq amt (cdr amt))
      (let ((list-elt mouse-wheel-scroll-amount))
	(while (consp (setq amt (pop list-elt))))))
    (if (floatp amt) (setq amt (1+ (truncate (* amt (window-height))))))
    (when (and mouse-wheel-progressive-speed (numberp amt))
      ;; When the double-mouse-N comes in, a mouse-N has been executed already,
      ;; So by adding things up we get a squaring up (1, 3, 6, 10, 15, ...).
      (setq amt (* amt (event-click-count event))))
    (unwind-protect
	(let ((button (mwheel-event-button event)))
	  (cond ((eq button mouse-wheel-down-event)
                 (condition-case nil (funcall mwheel-scroll-down-function amt)
                   ;; Make sure we do indeed scroll to the beginning of
                   ;; the buffer.
                   (beginning-of-buffer
                    (unwind-protect
                        (funcall mwheel-scroll-down-function)
                      ;; If the first scroll succeeded, then some scrolling
                      ;; is possible: keep scrolling til the beginning but
                      ;; do not signal an error.  For some reason, we have
                      ;; to do it even if the first scroll signaled an
                      ;; error, because otherwise the window is recentered
                      ;; for a reason that escapes me.  This problem seems
                      ;; to only affect scroll-down.  --Stef
                      (set-window-start (selected-window) (point-min))))))
		((eq button mouse-wheel-up-event)
                 (condition-case nil (funcall mwheel-scroll-up-function amt)
                   ;; Make sure we do indeed scroll to the end of the buffer.
                   (end-of-buffer (while t (funcall mwheel-scroll-up-function)))))
		(t (error "Bad binding in mwheel-scroll"))))
      (if curwin (select-window curwin)))
    ;; If there is a temporarily active region, deactivate it iff
    ;; scrolling moves point.
    (when opoint
      (with-current-buffer buffer
	(when (/= opoint (point))
	  (deactivate-mark)))))
  (when (and mouse-wheel-click-event mouse-wheel-inhibit-click-time)
    (if mwheel-inhibit-click-event-timer
	(cancel-timer mwheel-inhibit-click-event-timer)
      (add-hook 'pre-command-hook 'mwheel-filter-click-events))
    (setq mwheel-inhibit-click-event-timer
	  (run-with-timer mouse-wheel-inhibit-click-time nil
			  'mwheel-inhibit-click-timeout))))
(defvar mwheel-installed-bindings nil)
;; preloaded ;;;###autoload
(define-minor-mode mouse-wheel-mode
  "Toggle mouse wheel support.
With prefix argument ARG, turn on if positive, otherwise off.
Return non-nil if the new state is enabled."
  :init-value t
  ;; We'd like to use custom-initialize-set here so the setup is done
  ;; before dumping, but at the point where the defcustom is evaluated,
  ;; the corresponding function isn't defined yet, so
  ;; custom-initialize-set signals an error.
  :initialize 'custom-initialize-delay
  :global t
  :group 'mouse
  ;; Remove previous bindings, if any.
  (while mwheel-installed-bindings
    (let ((key (pop mwheel-installed-bindings)))
      (when (eq (lookup-key (current-global-map) key) 'mwheel-scroll)
        (global-unset-key key))))
  ;; Setup bindings as needed.
  (when mouse-wheel-mode
    (dolist (event (list mouse-wheel-down-event mouse-wheel-up-event))
      (dolist (key (mapcar (lambda (amt) `[(,@(if (consp amt) (car amt)) ,event)])
                           mouse-wheel-scroll-amount))
        (global-set-key key 'mwheel-scroll)
        (push key mwheel-installed-bindings)))))
;;; Compatibility entry point
;; preloaded ;;;###autoload
(defun mwheel-install (&optional uninstall)
  "Enable mouse wheel support."
  (mouse-wheel-mode (if uninstall -1 1)))
(provide 'mwheel)
;;; mwheel.el ends here
 |