image-mode.el 17.5 KB
Newer Older
1 2
;;; image-mode.el --- support for visiting image files
;;
Glenn Morris's avatar
Glenn Morris committed
3
;; Copyright (C) 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
4 5 6 7 8 9 10 11
;;
;; Author: Richard Stallman <rms@gnu.org>
;; Keywords: multimedia

;; 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
12
;; the Free Software Foundation; either version 3, or (at your option)
13 14 15 16 17 18 19 20 21
;; 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
Lute Kamstra's avatar
Lute Kamstra committed
22 23
;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
;; Boston, MA 02110-1301, USA.
24 25 26 27 28 29 30 31 32 33 34 35 36 37

;;; Commentary:

;; Defines a major mode for visiting image files
;; that allows conversion between viewing the text of the file
;; and viewing the file as an image.  Viewing the image
;; works by putting a `display' text-property on the
;; image data, with the image-data still present underneath; if the
;; resulting buffer file is saved to another name it will correctly save
;; the image data to the new file.

;;; Code:

(require 'image)
38
(eval-when-compile (require 'cl))
39

40 41 42 43 44
;;;###autoload (push '("\\.jpe?g\\'"    . image-mode) auto-mode-alist)
;;;###autoload (push '("\\.png\\'"      . image-mode) auto-mode-alist)
;;;###autoload (push '("\\.gif\\'"      . image-mode) auto-mode-alist)
;;;###autoload (push '("\\.tiff?\\'"    . image-mode) auto-mode-alist)
;;;###autoload (push '("\\.p[bpgn]m\\'" . image-mode) auto-mode-alist)
45 46

;;;###autoload (push '("\\.x[bp]m\\'"   . c-mode)     auto-mode-alist)
47
;;;###autoload (push '("\\.x[bp]m\\'"   . image-mode-maybe) auto-mode-alist)
48

49 50 51
;;;###autoload (push '("\\.svgz?\\'"    . xml-mode)   auto-mode-alist)
;;;###autoload (push '("\\.svgz?\\'"    . image-mode-maybe) auto-mode-alist)

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
;;; Image mode window-info management.

(defvar image-mode-winprops-alist t)
(make-variable-buffer-local 'image-mode-winprops-alist)

(defvar image-mode-new-window-functions nil
  "Special hook run when image data is requested in a new window.
It is called with one argument, the initial WINPROPS.")

(defun image-mode-winprops (&optional window)
  "Return winprops of WINDOW.
A winprops object has the shape (WINDOW . ALIST)."
  (unless window (setq window (selected-window)))
  (let ((winprops (assq window image-mode-winprops-alist)))
    ;; For new windows, set defaults from the latest.
    (unless winprops
      (setq winprops (cons window
                           (copy-alist (cdar image-mode-winprops-alist))))
      (run-hook-with-args 'image-mode-new-window-functions winprops))
    ;; Move window to front.
    (setq image-mode-winprops-alist
          (cons winprops (delq winprops image-mode-winprops-alist)))
    winprops))

(defun image-mode-window-get (prop &optional winprops)
  (unless (consp winprops) (setq winprops (image-mode-winprops winprops)))
  (cdr (assq prop (cdr winprops))))

(defsetf image-mode-window-get (prop &optional winprops) (val)
  `(image-mode-window-put ,prop ,val ,winprops))

(defun image-mode-window-put (prop val &optional winprops)
  (unless (consp winprops) (setq winprops (image-mode-winprops winprops)))
  (setcdr winprops (cons (cons prop val)
                         (delq (assq prop (cdr winprops)) (cdr winprops)))))

(defun image-set-window-vscroll (vscroll)
  (setf (image-mode-window-get 'vscroll) vscroll)
  (set-window-vscroll (selected-window) vscroll))

(defun image-set-window-hscroll (ncol)
93
  (setf (image-mode-window-get 'hscroll) ncol)
94 95 96
  (set-window-hscroll (selected-window) ncol))

(defun image-mode-reapply-winprops ()
97 98 99
  ;; When set-window-buffer, set hscroll and vscroll to what they were
  ;; last time the image was displayed in this window.
  (when (listp image-mode-winprops-alist)
100
    (let* ((winprops (image-mode-winprops))
101 102
           (hscroll (image-mode-window-get 'hscroll winprops))
           (vscroll (image-mode-window-get 'vscroll winprops)))
103 104
      (if hscroll (set-window-hscroll (selected-window) hscroll))
      (if vscroll (set-window-vscroll (selected-window) vscroll)))))
105

106 107 108 109 110 111 112 113 114
(defun image-mode-setup-winprops ()
  ;; Record current scroll settings.
  (unless (listp image-mode-winprops-alist)
    (setq image-mode-winprops-alist nil))
  (add-hook 'window-configuration-change-hook
 	    'image-mode-reapply-winprops nil t))

;;; Image scrolling functions

115 116 117 118 119 120
(defun image-get-display-property ()
  (get-char-property (point-min) 'display
                     ;; There might be different images for different displays.
                     (if (eq (window-buffer) (current-buffer))
                         (selected-window))))

121 122 123 124 125 126
(defun image-forward-hscroll (&optional n)
  "Scroll image in current window to the left by N character widths.
Stop if the right edge of the image is reached."
  (interactive "p")
  (cond ((= n 0) nil)
	((< n 0)
127
	 (image-set-window-hscroll (max 0 (+ (window-hscroll) n))))
128
	(t
129
	 (let* ((image (image-get-display-property))
130 131 132
		(edges (window-inside-edges))
		(win-width (- (nth 2 edges) (nth 0 edges)))
		(img-width (ceiling (car (image-size image)))))
133
	   (image-set-window-hscroll (min (max 0 (- img-width win-width))
134
					  (+ n (window-hscroll))))))))
135 136 137 138 139 140 141 142 143 144 145 146 147

(defun image-backward-hscroll (&optional n)
  "Scroll image in current window to the right by N character widths.
Stop if the left edge of the image is reached."
  (interactive "p")
  (image-forward-hscroll (- n)))

(defun image-next-line (&optional n)
  "Scroll image in current window upward by N lines.
Stop if the bottom edge of the image is reached."
  (interactive "p")
  (cond ((= n 0) nil)
	((< n 0)
148
	 (image-set-window-vscroll (max 0 (+ (window-vscroll) n))))
149
	(t
150
	 (let* ((image (image-get-display-property))
151 152 153
		(edges (window-inside-edges))
		(win-height (- (nth 3 edges) (nth 1 edges)))
		(img-height (ceiling (cdr (image-size image)))))
154
	   (image-set-window-vscroll (min (max 0 (- img-height win-height))
155
					  (+ n (window-vscroll))))))))
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

(defun image-previous-line (&optional n)
  "Scroll image in current window downward by N lines.
Stop if the top edge of the image is reached."
  (interactive "p")
  (image-next-line (- n)))

(defun image-scroll-up (&optional n)
  "Scroll image in current window upward by N lines.
Stop if the bottom edge of the image is reached.
If ARG is omitted or nil, scroll upward by a near full screen.
A near full screen is `next-screen-context-lines' less than a full screen.
Negative ARG means scroll downward.
If ARG is the atom `-', scroll downward by nearly full screen.
When calling from a program, supply as argument a number, nil, or `-'."
  (interactive "P")
  (cond ((null n)
	 (let* ((edges (window-inside-edges))
		(win-height (- (nth 3 edges) (nth 1 edges))))
	   (image-next-line
	    (max 0 (- win-height next-screen-context-lines)))))
	((eq n '-)
	 (let* ((edges (window-inside-edges))
		(win-height (- (nth 3 edges) (nth 1 edges))))
	   (image-next-line
	    (min 0 (- next-screen-context-lines win-height)))))
	(t (image-next-line (prefix-numeric-value n)))))

(defun image-scroll-down (&optional n)
185
  "Scroll image in current window downward by N lines.
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
Stop if the top edge of the image is reached.
If ARG is omitted or nil, scroll downward by a near full screen.
A near full screen is `next-screen-context-lines' less than a full screen.
Negative ARG means scroll upward.
If ARG is the atom `-', scroll upward by nearly full screen.
When calling from a program, supply as argument a number, nil, or `-'."
  (interactive "P")
  (cond ((null n)
	 (let* ((edges (window-inside-edges))
		(win-height (- (nth 3 edges) (nth 1 edges))))
	   (image-next-line
	    (min 0 (- next-screen-context-lines win-height)))))
	((eq n '-)
	 (let* ((edges (window-inside-edges))
		(win-height (- (nth 3 edges) (nth 1 edges))))
	   (image-next-line
	    (max 0 (- win-height next-screen-context-lines)))))
	(t (image-next-line (- (prefix-numeric-value n))))))

(defun image-bol (arg)
  "Scroll horizontally to the left edge of the image in the current window.
With argument ARG not nil or 1, move forward ARG - 1 lines first,
stopping if the top or bottom edge of the image is reached."
  (interactive "p")
  (and arg
       (/= (setq arg (prefix-numeric-value arg)) 1)
       (image-next-line (- arg 1)))
213
  (image-set-window-hscroll 0))
214 215 216 217 218 219 220 221 222

(defun image-eol (arg)
  "Scroll horizontally to the right edge of the image in the current window.
With argument ARG not nil or 1, move forward ARG - 1 lines first,
stopping if the top or bottom edge of the image is reached."
  (interactive "p")
  (and arg
       (/= (setq arg (prefix-numeric-value arg)) 1)
       (image-next-line (- arg 1)))
223
  (let* ((image (image-get-display-property))
224 225 226
	 (edges (window-inside-edges))
	 (win-width (- (nth 2 edges) (nth 0 edges)))
	 (img-width (ceiling (car (image-size image)))))
227
    (image-set-window-hscroll (max 0 (- img-width win-width)))))
228 229 230 231

(defun image-bob ()
  "Scroll to the top-left corner of the image in the current window."
  (interactive)
232 233
  (image-set-window-hscroll 0)
  (image-set-window-vscroll 0))
234 235 236 237

(defun image-eob ()
  "Scroll to the bottom-right corner of the image in the current window."
  (interactive)
238
  (let* ((image (image-get-display-property))
239 240 241 242 243
	 (edges (window-inside-edges))
	 (win-width (- (nth 2 edges) (nth 0 edges)))
	 (img-width (ceiling (car (image-size image))))
	 (win-height (- (nth 3 edges) (nth 1 edges)))
	 (img-height (ceiling (cdr (image-size image)))))
244 245
    (image-set-window-hscroll (max 0 (- img-width win-width)))
    (image-set-window-vscroll (max 0 (- img-height win-height)))))
246 247 248

;;; Image Mode setup

Juri Linkov's avatar
Juri Linkov committed
249 250 251 252 253
(defvar image-type nil
  "Current image type.
This variable is used to display the current image type in the mode line.")
(make-variable-buffer-local 'image-type)

254
(defvar image-mode-map
255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270
  (let ((map (make-sparse-keymap)))
    (define-key map "\C-c\C-c" 'image-toggle-display)
    (define-key map [remap forward-char] 'image-forward-hscroll)
    (define-key map [remap backward-char] 'image-backward-hscroll)
    (define-key map [remap previous-line] 'image-previous-line)
    (define-key map [remap next-line] 'image-next-line)
    (define-key map [remap scroll-up] 'image-scroll-up)
    (define-key map [remap scroll-down] 'image-scroll-down)
    (define-key map [remap move-beginning-of-line] 'image-bol)
    (define-key map [remap move-end-of-line] 'image-eol)
    (define-key map [remap beginning-of-buffer] 'image-bob)
    (define-key map [remap end-of-buffer] 'image-eob)
    map)
  "Major mode keymap for viewing images in Image mode.")

(defvar image-mode-text-map
271 272 273
  (let ((map (make-sparse-keymap)))
    (define-key map "\C-c\C-c" 'image-toggle-display)
    map)
274
  "Major mode keymap for viewing images as text in Image mode.")
275

276
(defvar bookmark-make-record-function)
Glenn Morris's avatar
Glenn Morris committed
277

278 279 280 281 282 283 284
;;;###autoload
(defun image-mode ()
  "Major mode for image files.
You can use \\<image-mode-map>\\[image-toggle-display]
to toggle between display as an image and display as text."
  (interactive)
  (kill-all-local-variables)
Juri Linkov's avatar
Juri Linkov committed
285
  (setq mode-name "Image[text]")
286
  (setq major-mode 'image-mode)
287
  ;; Use our own bookmarking function for images.
288 289
  (set (make-local-variable 'bookmark-make-record-function)
       'image-bookmark-make-record)
290 291

  ;; Keep track of [vh]scroll when switching buffers
292
  (image-mode-setup-winprops)
293

294
  (add-hook 'change-major-mode-hook 'image-toggle-display-text nil t)
295
  (if (and (display-images-p)
296
	   (not (image-get-display-property)))
297 298 299
      (image-toggle-display)
    ;; Set next vars when image is already displayed but local
    ;; variables were cleared by kill-all-local-variables
300
    (use-local-map image-mode-map)
301
    (setq cursor-type nil truncate-lines t))
302 303 304 305
  (run-mode-hooks 'image-mode-hook)
  (if (display-images-p)
      (message "%s" (concat
		     (substitute-command-keys
306
		      "Type \\[image-toggle-display] to view as ")
307
		     (if (image-get-display-property)
308
			 "text" "an image") "."))))
309 310 311 312 313 314

;;;###autoload
(define-minor-mode image-minor-mode
  "Toggle Image minor mode.
With arg, turn Image minor mode on if arg is positive, off otherwise.
See the command `image-mode' for more information on this mode."
Juri Linkov's avatar
Juri Linkov committed
315
  nil (:eval (format " Image[%s]" image-type)) image-mode-text-map
316 317
  :group 'image
  :version "22.1"
318 319
  (if (not image-minor-mode)
      (image-toggle-display-text)
320
    (if (image-get-display-property)
Juri Linkov's avatar
Juri Linkov committed
321 322
	(setq cursor-type nil truncate-lines t)
      (setq image-type "text"))
323
    (add-hook 'change-major-mode-hook (lambda () (image-minor-mode -1)) nil t)
Deepak Goel's avatar
Deepak Goel committed
324
    (message "%s" (concat (substitute-command-keys
325
			   "Type \\[image-toggle-display] to view the image as ")
326
			  (if (image-get-display-property)
327
			      "text" "an image") "."))))
328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347

;;;###autoload
(defun image-mode-maybe ()
  "Set major or minor mode for image files.
Set Image major mode only when there are no other major modes
associated with a filename in `auto-mode-alist'.  When an image
filename matches another major mode in `auto-mode-alist' then
set that major mode and Image minor mode.

See commands `image-mode' and `image-minor-mode' for more
information on these modes."
  (interactive)
  (let* ((mode-alist
	  (delq nil (mapcar
		     (lambda (elt)
		       (unless (memq (or (car-safe (cdr elt)) (cdr elt))
				     '(image-mode image-mode-maybe))
			 elt))
		     auto-mode-alist))))
    (if (assoc-default buffer-file-name mode-alist 'string-match)
348 349
	(let ((auto-mode-alist mode-alist)
	      (magic-mode-alist nil))
350 351 352 353 354 355
	  (set-auto-mode)
	  (image-minor-mode t))
      (image-mode))))

(defun image-toggle-display-text ()
  "Showing the text of the image file."
356
  (if (image-get-display-property)
357
      (image-toggle-display)))
358

359 360 361
(defvar archive-superior-buffer)
(defvar tar-superior-buffer)

362 363 364 365 366
(defun image-toggle-display ()
  "Start or stop displaying an image file as the actual image.
This command toggles between showing the text of the image file
and showing the image as an image."
  (interactive)
367
  (if (image-get-display-property)
368
      (let ((inhibit-read-only t)
Richard M. Stallman's avatar
Richard M. Stallman committed
369 370
	    (buffer-undo-list t)
	    (modified (buffer-modified-p)))
371 372 373
	(remove-list-of-text-properties (point-min) (point-max)
					'(display intangible read-nonsticky
						  read-only front-sticky))
Richard M. Stallman's avatar
Richard M. Stallman committed
374
	(set-buffer-modified-p modified)
375 376
	(kill-local-variable 'cursor-type)
	(kill-local-variable 'truncate-lines)
377 378
	(kill-local-variable 'auto-hscroll-mode)
	(use-local-map image-mode-text-map)
Juri Linkov's avatar
Juri Linkov committed
379 380 381
	(setq image-type "text")
	(if (eq major-mode 'image-mode)
	    (setq mode-name "Image[text]"))
382 383
	(if (called-interactively-p)
	    (message "Repeat this command to go back to displaying the image")))
384 385
    ;; Turn the image data into a real image, but only if the whole file
    ;; was inserted
386
    (let* ((filename (buffer-file-name))
Juri Linkov's avatar
Juri Linkov committed
387 388 389 390 391 392 393 394 395 396 397 398 399 400
	   (data-p (not (and filename
			     (file-readable-p filename)
			     (not (file-remote-p filename))
			     (not (buffer-modified-p))
			     (not (and (boundp 'archive-superior-buffer)
				       archive-superior-buffer))
			     (not (and (boundp 'tar-superior-buffer)
				       tar-superior-buffer)))))
	   (file-or-data (if data-p
			     (string-make-unibyte
			      (buffer-substring-no-properties (point-min) (point-max)))
			   filename))
	   (type (image-type file-or-data nil data-p))
	   (image (create-image file-or-data type data-p))
401 402
	   (props
	    `(display ,image
403 404 405
		      intangible ,image
		      rear-nonsticky (display intangible)
		      read-only t front-sticky (read-only)))
406
	   (inhibit-read-only t)
Richard M. Stallman's avatar
Richard M. Stallman committed
407 408
	   (buffer-undo-list t)
	   (modified (buffer-modified-p)))
409
      (image-refresh image)
410
      (add-text-properties (point-min) (point-max) props)
Richard M. Stallman's avatar
Richard M. Stallman committed
411
      (set-buffer-modified-p modified)
412 413 414 415 416 417
      ;; Inhibit the cursor when the buffer contains only an image,
      ;; because cursors look very strange on top of images.
      (setq cursor-type nil)
      ;; This just makes the arrow displayed in the right fringe
      ;; area look correct when the image is wider than the window.
      (setq truncate-lines t)
418 419 420
      ;; Allow navigation of large images
      (set (make-local-variable 'auto-hscroll-mode) nil)
      (use-local-map image-mode-map)
Juri Linkov's avatar
Juri Linkov committed
421 422 423
      (setq image-type type)
      (if (eq major-mode 'image-mode)
	  (setq mode-name (format "Image[%s]" type)))
424 425
      (if (called-interactively-p)
	  (message "Repeat this command to go back to displaying the file as text")))))
426

427 428
;;; Support for bookmark.el

429
(defun image-bookmark-make-record (annotation)
430 431 432 433 434 435 436 437 438 439 440 441 442 443 444
  (let ((the-record
         `((filename   . ,(buffer-file-name))
	   (image-type . ,image-type)
	   (position   . ,(point))
	   (handler    . image-bookmark-jump))))

    ;; Take no chances with text properties
    (set-text-properties 0 (length annotation) nil annotation)

    (when annotation
      (nconc the-record (list (cons 'annotation annotation))))

    ;; Finally, return the completed record.
    the-record))

Glenn Morris's avatar
Glenn Morris committed
445 446 447 448
(declare-function bookmark-get-filename        "bookmark" (bookmark))
(declare-function bookmark-get-bookmark-record "bookmark" (bookmark))
(declare-function bookmark-get-position        "bookmark" (bookmark))

449 450
;;;###autoload
(defun image-bookmark-jump (bmk)
451
  ;; This implements the `handler' function interface for record type
452
  ;; returned by `bookmark-make-record-function', which see.
453 454 455 456 457 458 459 460 461
  (save-window-excursion
    (let ((filename (bookmark-get-filename bmk))
	  (type (cdr (assq 'image-type (bookmark-get-bookmark-record bmk))))
	  (pos  (bookmark-get-position bmk)))
      (find-file filename)
      (when (not (string= image-type type))
	(image-toggle-display))
      (when (string= image-type "text")
	(goto-char pos))
462
      `((buffer ,(current-buffer)) (position ,(point))))))
463

464 465
(provide 'image-mode)

466
;; arch-tag: b5b2b7e6-26a7-4b79-96e3-1546b5c4c6cb
467
;;; image-mode.el ends here