-;;; image-mode.el --- support for visiting image files
+;;; image-mode.el --- support for visiting image files -*- lexical-binding: t -*-
;;
-;; Copyright (C) 2005-2011 Free Software Foundation, Inc.
+;; Copyright (C) 2005-2013 Free Software Foundation, Inc.
;;
;; Author: Richard Stallman <rms@gnu.org>
;; Keywords: multimedia
;; resulting buffer file is saved to another name it will correctly save
;; the image data to the new file.
+;; Todo:
+
+;; Consolidate with doc-view to make them work on directories of images or on
+;; image files containing various "pages".
+
;;; Code:
(require 'image)
-(eval-when-compile (require 'cl))
+(eval-when-compile (require 'cl-lib))
;;; Image mode window-info management.
-(defvar image-mode-winprops-alist t)
-(make-variable-buffer-local 'image-mode-winprops-alist)
+(defvar-local image-mode-winprops-alist t)
(defvar image-mode-new-window-functions nil
"Special hook run when image data is requested in a new window.
(defun image-mode-winprops (&optional window cleanup)
"Return winprops of WINDOW.
-A winprops object has the shape (WINDOW . ALIST)."
+A winprops object has the shape (WINDOW . ALIST).
+WINDOW defaults to `selected-window' if it displays the current buffer, and
+otherwise it defaults to t, used for times when the buffer is not displayed."
(cond ((null window)
- (setq window (selected-window)))
+ (setq window
+ (if (eq (current-buffer) (window-buffer)) (selected-window) t)))
+ ((eq window t))
((not (windowp window))
(error "Not a window: %s" window)))
(when cleanup
(setq image-mode-winprops-alist
(delq nil (mapcar (lambda (winprop)
- (if (window-live-p (car-safe winprop))
- winprop))
+ (let ((w (car-safe winprop)))
+ (if (or (not (windowp w)) (window-live-p w))
+ winprop)))
image-mode-winprops-alist))))
(let ((winprops (assq window image-mode-winprops-alist)))
;; For new windows, set defaults from the latest.
winprops))
(defun image-mode-window-get (prop &optional winprops)
+ (declare (gv-setter (lambda (val)
+ `(image-mode-window-put ,prop ,val ,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)
(interactive "p")
(image-forward-hscroll (- n)))
-(defun image-next-line (&optional n)
+(defun image-next-line (n)
"Scroll image in current window upward by N lines.
Stop if the bottom edge of the image is reached."
(interactive "p")
;; Adjust frame and image size.
(defun image-mode-fit-frame ()
- "Fit the frame to the current image.
+ "Toggle whether to fit the frame to the current image.
This function assumes the current frame has only one window."
;; FIXME: This does not take into account decorations like mode-line,
;; minibuffer, header-line, ...
(define-key map "\C-c\C-c" 'image-toggle-display)
(define-key map (kbd "SPC") 'image-scroll-up)
(define-key map (kbd "DEL") 'image-scroll-down)
+ (define-key map (kbd "RET") 'image-toggle-animation)
(define-key map [remap forward-char] 'image-forward-hscroll)
(define-key map [remap backward-char] 'image-backward-hscroll)
(define-key map [remap right-char] 'image-forward-hscroll)
(add-hook 'change-major-mode-hook 'image-toggle-display-text nil t)
(add-hook 'after-revert-hook 'image-after-revert-hook nil t)
(run-mode-hooks 'image-mode-hook)
- (message "%s" (concat
- (substitute-command-keys
- "Type \\[image-toggle-display] to view the image as ")
- (if (image-get-display-property)
- "text" "an image") ".")))
+ (let ((image (image-get-display-property))
+ (msg1 (substitute-command-keys
+ "Type \\[image-toggle-display] to view the image as ")))
+ (cond
+ ((null image)
+ (message "%s" (concat msg1 "an image.")))
+ ((image-animated-p image)
+ (message "%s"
+ (concat msg1 "text, or "
+ (substitute-command-keys
+ "\\[image-toggle-animation] to animate."))))
+ (t
+ (message "%s" (concat msg1 "text."))))))
+
(error
(image-mode-as-text)
(funcall
(if (called-interactively-p 'any) 'error 'message)
"Cannot display image: %s" (cdr err)))))
+
;;;###autoload
(define-minor-mode image-minor-mode
- "Toggle Image minor mode.
-With arg, turn Image minor mode on if arg is positive, off otherwise.
-It provides the key \\<image-mode-map>\\[image-toggle-display] \
-to switch back to `image-mode'
-to display an image file as the actual image."
+ "Toggle Image minor mode in this buffer.
+With a prefix argument ARG, enable Image minor mode if ARG is
+positive, and disable it otherwise. If called from Lisp, enable
+the mode if ARG is omitted or nil.
+
+Image minor mode provides the key \\<image-mode-map>\\[image-toggle-display],
+to switch back to `image-mode' and display an image file as the
+actual image."
nil (:eval (if image-type (format " Image[%s]" image-type) " Image"))
image-minor-mode-map
:group 'image
(buffer-undo-list t)
(modified (buffer-modified-p)))
(remove-list-of-text-properties (point-min) (point-max)
- '(display intangible read-nonsticky
+ '(display read-nonsticky ;; intangible
read-only front-sticky))
(set-buffer-modified-p modified)
(if (called-interactively-p 'any)
"Show the image of the image file.
Turn the image data into a real image, but only if the whole file
was inserted."
- (unless (derived-mode-p 'image-mode major-mode)
+ (unless (derived-mode-p 'image-mode)
(error "The buffer is not in Image mode"))
(let* ((filename (buffer-file-name))
(data-p (not (and filename
(buffer-substring-no-properties (point-min) (point-max)))
filename))
(type (image-type file-or-data nil data-p))
- (image0 (create-animated-image file-or-data type data-p))
- (image (append image0
- (image-transform-properties image0)))
- (props
- `(display ,image
- intangible ,image
- rear-nonsticky (display intangible)
- read-only t front-sticky (read-only)))
+ (image (create-image file-or-data type data-p))
(inhibit-read-only t)
(buffer-undo-list t)
- (modified (buffer-modified-p)))
+ (modified (buffer-modified-p))
+ props)
+
+ ;; Discard any stale image data before looking it up again.
(image-flush image)
+ (setq image (append image (image-transform-properties image)))
+ (setq props
+ `(display ,image
+ ;; intangible ,image
+ rear-nonsticky (display) ;; intangible
+ read-only t front-sticky (read-only)))
+
(let ((buffer-file-truename nil)) ; avoid changing dir mtime by lock_file
(add-text-properties (point-min) (point-max) props)
(restore-buffer-modified-p modified))
(setq image-type type)
(if (eq major-mode 'image-mode)
(setq mode-name (format "Image[%s]" type)))
+ (image-transform-check-size)
(if (called-interactively-p 'any)
(message "Repeat this command to go back to displaying the file as text"))))
(get-buffer-window-list (current-buffer) 'nomini 'visible))
(image-toggle-display-image)))
+\f
+;;; Animated images
+
+(defcustom image-animate-loop nil
+ "Non-nil means animated images loop forever, rather than playing once."
+ :type 'boolean
+ :version "24.1"
+ :group 'image)
+
+(defun image-toggle-animation ()
+ "Start or stop animating the current image.
+If `image-animate-loop' is non-nil, animation loops forever.
+Otherwise it plays once, then stops."
+ (interactive)
+ (let ((image (image-get-display-property))
+ animation)
+ (cond
+ ((null image)
+ (error "No image is present"))
+ ((null (setq animation (image-animated-p image)))
+ (message "No image animation."))
+ (t
+ (let ((timer (image-animate-timer image)))
+ (if timer
+ (cancel-timer timer)
+ (let ((index (plist-get (cdr image) :index)))
+ ;; If we're at the end, restart.
+ (and index
+ (>= index (1- (car animation)))
+ (setq index nil))
+ (image-animate image index
+ (if image-animate-loop t)))))))))
+
\f
;;; Support for bookmark.el
(declare-function bookmark-make-record-default
(image-toggle-display))))
\f
-(defvar image-transform-minor-mode-map
- (let ((map (make-sparse-keymap)))
- ;; (define-key map [(control ?+)] 'image-scale-in)
- ;; (define-key map [(control ?-)] 'image-scale-out)
- ;; (define-key map [(control ?=)] 'image-scale-none)
- ;; (define-key map "c f h" 'image-scale-fit-height)
- ;; (define-key map "c ]" 'image-rotate-right)
- map)
- "Minor mode keymap `image-transform-mode'.")
+;; Not yet implemented.
+;; (defvar image-transform-minor-mode-map
+;; (let ((map (make-sparse-keymap)))
+;; ;; (define-key map [(control ?+)] 'image-scale-in)
+;; ;; (define-key map [(control ?-)] 'image-scale-out)
+;; ;; (define-key map [(control ?=)] 'image-scale-none)
+;; ;; (define-key map "c f h" 'image-scale-fit-height)
+;; ;; (define-key map "c ]" 'image-rotate-right)
+;; map)
+;; "Minor mode keymap `image-transform-mode'.")
+;;
+;; (define-minor-mode image-transform-mode
+;; "Minor mode for scaling and rotating images.
+;; With a prefix argument ARG, enable the mode if ARG is positive,
+;; and disable it otherwise. If called from Lisp, enable the mode
+;; if ARG is omitted or nil. This minor mode requires Emacs to have
+;; been compiled with ImageMagick support."
+;; nil "image-transform" image-transform-minor-mode-map)
-(define-minor-mode image-transform-mode
- "Minor mode for scaling and rotating images.
-This minor mode has no effect unless Emacs is compiled with
-ImageMagick support."
- nil "image-transform" image-transform-minor-mode-map)
+;; FIXME this doesn't seem mature yet. Document in manual when it is.
(defvar image-transform-resize nil
"The image resize operation.
Its value should be one of the following:
- nil, meaning no resizing.
- `fit-height', meaning to fit the image to the window height.
- `fit-width', meaning to fit the image to the window width.
- - A number, which is a scale factor (the default size is 100).")
-
-(defvar image-transform-rotation 0.0)
-
-(defun image-transform-properties (display)
- "Rescale and/or rotate the current image.
-The scale factor and rotation angle are given by the variables
-`image-transform-resize' and `image-transform-rotation'. This
-takes effect only if Emacs is compiled with ImageMagick support."
- (let* ((size (image-size display t))
- (height
- (cond
- ((numberp image-transform-resize)
- (unless (= image-transform-resize 100)
- (* image-transform-resize (cdr size))))
- ((eq image-transform-resize 'fit-height)
- (- (nth 3 (window-inside-pixel-edges))
- (nth 1 (window-inside-pixel-edges))))))
- (width (if (eq image-transform-resize 'fit-width)
- (- (nth 2 (window-inside-pixel-edges))
- (nth 0 (window-inside-pixel-edges))))))
- ;;TODO fit-to-* should consider the rotation angle
- `(,@(if height (list :height height))
- ,@(if width (list :width width))
- ,@(if (not (equal 0.0 image-transform-rotation))
- (list :rotation image-transform-rotation)))))
+ - A number, which is a scale factor (the default size is 1).")
+
+(defvar image-transform-scale 1.0
+ "The scale factor of the image being displayed.")
+
+(defvar image-transform-rotation 0.0
+ "Rotation angle for the image in the current Image mode buffer.")
+
+(defvar image-transform-right-angle-fudge 0.0001
+ "Snap distance to a multiple of a right angle.
+There's no deep theory behind the default value, it should just
+be somewhat larger than ImageMagick's MagickEpsilon.")
+
+(defsubst image-transform-width (width height)
+ "Return the bounding box width of a rotated WIDTH x HEIGHT rectangle.
+The rotation angle is the value of `image-transform-rotation' in degrees."
+ (let ((angle (degrees-to-radians image-transform-rotation)))
+ ;; Assume, w.l.o.g., that the vertices of the rectangle have the
+ ;; coordinates (+-w/2, +-h/2) and that (0, 0) is the center of the
+ ;; rotation by the angle A. The projections onto the first axis
+ ;; of the vertices of the rotated rectangle are +- (w/2) cos A +-
+ ;; (h/2) sin A, and the difference between the largest and the
+ ;; smallest of the four values is the expression below.
+ (+ (* width (abs (cos angle))) (* height (abs (sin angle))))))
+
+;; The following comment and code snippet are from
+;; ImageMagick-6.7.4-4/magick/distort.c
+
+;; /* Set the output image geometry to calculated 'best fit'.
+;; Yes this tends to 'over do' the file image size, ON PURPOSE!
+;; Do not do this for DePolar which needs to be exact for virtual tiling.
+;; */
+;; if ( fix_bounds ) {
+;; geometry.x = (ssize_t) floor(min.x-0.5);
+;; geometry.y = (ssize_t) floor(min.y-0.5);
+;; geometry.width=(size_t) ceil(max.x-geometry.x+0.5);
+;; geometry.height=(size_t) ceil(max.y-geometry.y+0.5);
+;; }
+
+;; Other parts of the same file show that here the origin is in the
+;; left lower corner of the image rectangle, the center of the
+;; rotation is the center of the rectangle and min.x and max.x
+;; (resp. min.y and max.y) are the smallest and the largest of the
+;; projections of the vertices onto the first (resp. second) axis.
+
+(defun image-transform-fit-width (width height length)
+ "Return (w . h) so that a rotated w x h image has exactly width LENGTH.
+The rotation angle is the value of `image-transform-rotation'.
+Write W for WIDTH and H for HEIGHT. Then the w x h rectangle is
+an \"approximately uniformly\" scaled W x H rectangle, which
+currently means that w is one of floor(s W) + {0, 1, -1} and h is
+floor(s H), where s can be recovered as the value of `image-transform-scale'.
+The value of `image-transform-rotation' may be replaced by
+a slightly different angle. Currently this is done for values
+close to a multiple of 90, see `image-transform-right-angle-fudge'."
+ (cond ((< (abs (- (mod (+ image-transform-rotation 90) 180) 90))
+ image-transform-right-angle-fudge)
+ (cl-assert (not (zerop width)) t)
+ (setq image-transform-rotation
+ (float (round image-transform-rotation))
+ image-transform-scale (/ (float length) width))
+ (cons length nil))
+ ((< (abs (- (mod (+ image-transform-rotation 45) 90) 45))
+ image-transform-right-angle-fudge)
+ (cl-assert (not (zerop height)) t)
+ (setq image-transform-rotation
+ (float (round image-transform-rotation))
+ image-transform-scale (/ (float length) height))
+ (cons nil length))
+ (t
+ (cl-assert (not (and (zerop width) (zerop height))) t)
+ (setq image-transform-scale
+ (/ (float (1- length)) (image-transform-width width height)))
+ ;; Assume we have a w x h image and an angle A, and let l =
+ ;; l(w, h) = w |cos A| + h |sin A|, which is the actual width
+ ;; of the bounding box of the rotated image, as calculated by
+ ;; `image-transform-width'. The code snippet quoted above
+ ;; means that ImageMagick puts the rotated image in
+ ;; a bounding box of width L = 2 ceil((w+l+1)/2) - w.
+ ;; Elementary considerations show that this is equivalent to
+ ;; L - w being even and L-3 < l(w, h) <= L-1. In our case, L is
+ ;; the given `length' parameter and our job is to determine
+ ;; reasonable values for w and h which satisfy these
+ ;; conditions.
+ (let ((w (floor (* image-transform-scale width)))
+ (h (floor (* image-transform-scale height))))
+ ;; Let w and h as bound above. Then l(w, h) <= l(s W, s H)
+ ;; = L-1 < l(w+1, h+1) = l(w, h) + l(1, 1) <= l(w, h) + 2,
+ ;; hence l(w, h) > (L-1) - 2 = L-3.
+ (cons
+ (cond ((= (mod w 2) (mod length 2))
+ w)
+ ;; l(w+1, h) >= l(w, h) > L-3, but does l(w+1, h) <=
+ ;; L-1 hold?
+ ((<= (image-transform-width (1+ w) h) (1- length))
+ (1+ w))
+ ;; No, it doesn't, but this implies that l(w-1, h) =
+ ;; l(w+1, h) - l(2, 0) >= l(w+1, h) - 2 > (L-1) -
+ ;; 2 = L-3. Clearly, l(w-1, h) <= l(w, h) <= L-1.
+ (t
+ (1- w)))
+ h)))))
+
+(defun image-transform-check-size ()
+ "Check that the image exactly fits the width/height of the window.
+
+Do this for an image of type `imagemagick' to make sure that the
+elisp code matches the way ImageMagick computes the bounding box
+of a rotated image."
+ (when (and (not (numberp image-transform-resize))
+ (boundp 'image-type)
+ (eq image-type 'imagemagick))
+ (let ((size (image-display-size (image-get-display-property) t)))
+ (cond ((eq image-transform-resize 'fit-width)
+ (cl-assert (= (car size)
+ (- (nth 2 (window-inside-pixel-edges))
+ (nth 0 (window-inside-pixel-edges))))
+ t))
+ ((eq image-transform-resize 'fit-height)
+ (cl-assert (= (cdr size)
+ (- (nth 3 (window-inside-pixel-edges))
+ (nth 1 (window-inside-pixel-edges))))
+ t))))))
+
+(defun image-transform-properties (spec)
+ "Return rescaling/rotation properties for image SPEC.
+These properties are determined by the Image mode variables
+`image-transform-resize' and `image-transform-rotation'. The
+return value is suitable for appending to an image spec.
+
+Rescaling and rotation properties only take effect if Emacs is
+compiled with ImageMagick support."
+ (setq image-transform-scale 1.0)
+ (when (or image-transform-resize
+ (/= image-transform-rotation 0.0))
+ ;; Note: `image-size' looks up and thus caches the untransformed
+ ;; image. There's no easy way to prevent that.
+ (let* ((size (image-size spec t))
+ (resized
+ (cond
+ ((numberp image-transform-resize)
+ (unless (= image-transform-resize 1)
+ (setq image-transform-scale image-transform-resize)
+ (cons nil (floor (* image-transform-resize (cdr size))))))
+ ((eq image-transform-resize 'fit-width)
+ (image-transform-fit-width
+ (car size) (cdr size)
+ (- (nth 2 (window-inside-pixel-edges))
+ (nth 0 (window-inside-pixel-edges)))))
+ ((eq image-transform-resize 'fit-height)
+ (let ((res (image-transform-fit-width
+ (cdr size) (car size)
+ (- (nth 3 (window-inside-pixel-edges))
+ (nth 1 (window-inside-pixel-edges))))))
+ (cons (cdr res) (car res)))))))
+ `(,@(when (car resized)
+ (list :width (car resized)))
+ ,@(when (cdr resized)
+ (list :height (cdr resized)))
+ ,@(unless (= 0.0 image-transform-rotation)
+ (list :rotation image-transform-rotation))))))
(defun image-transform-set-scale (scale)
"Prompt for a number, and resize the current image by that amount.
ROTATION should be in degrees. This command has no effect unless
Emacs is compiled with ImageMagick support."
(interactive "nRotation angle (in degrees): ")
- ;;TODO 0 90 180 270 degrees are the only reasonable angles here
- ;;otherwise combining with rescaling will get very awkward
- (setq image-transform-rotation (float rotation))
+ (setq image-transform-rotation (float (mod rotation 360)))
(image-toggle-display-image))
(provide 'image-mode)