Commit bb0cb417 authored by Chong Yidong's avatar Chong Yidong
Browse files

(image-forward-hscroll, image-backward-hscroll)

(image-next-line, image-previous-line, image-scroll-up)
(image-scroll-down, image-bol, image-eol, image-bob, image-eob):
New functions.
(image-mode-map): Remap motion commands.
(image-mode-text-map): New keymap for viewing images as text.
(image-mode): Use image-mode-map.
(image-toggle-display): Toggle auto-hscroll-mode and mode keymaps.
parent 6db526f0
......@@ -43,11 +43,162 @@
;;;###autoload (push '("\\.p[bpgn]m\\'" . image-mode) auto-mode-alist)
;;;###autoload (push '("\\.x[bp]m\\'" . image-mode-maybe) auto-mode-alist)
;;; Image scrolling functions
(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)
(set-window-hscroll (selected-window)
(max 0 (+ (window-hscroll) n))))
(t
(let* ((image (get-text-property 1 'display))
(edges (window-inside-edges))
(win-width (- (nth 2 edges) (nth 0 edges)))
(img-width (ceiling (car (image-size image)))))
(set-window-hscroll (selected-window)
(min (max 0 (- img-width win-width))
(+ n (window-hscroll))))))))
(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)
(set-window-vscroll (selected-window)
(max 0 (+ (window-vscroll) n))))
(t
(let* ((image (get-text-property 1 'display))
(edges (window-inside-edges))
(win-height (- (nth 3 edges) (nth 1 edges)))
(img-height (ceiling (cdr (image-size image)))))
(set-window-vscroll (selected-window)
(min (max 0 (- img-height win-height))
(+ n (window-vscroll))))))))
(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)
"Scroll image in current window downward by N lines
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)))
(set-window-hscroll (selected-window) 0))
(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)))
(let* ((image (get-text-property 1 'display))
(edges (window-inside-edges))
(win-width (- (nth 2 edges) (nth 0 edges)))
(img-width (ceiling (car (image-size image)))))
(set-window-hscroll (selected-window)
(max 0 (- img-width win-width)))))
(defun image-bob ()
"Scroll to the top-left corner of the image in the current window."
(interactive)
(set-window-hscroll (selected-window) 0)
(set-window-vscroll (selected-window) 0))
(defun image-eob ()
"Scroll to the bottom-right corner of the image in the current window."
(interactive)
(let* ((image (get-text-property 1 'display))
(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)))))
(set-window-hscroll (selected-window) (max 0 (- img-width win-width)))
(set-window-vscroll (selected-window) (max 0 (- img-height win-height)))))
;;; Image Mode setup
(defvar image-mode-map
(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
(let ((map (make-sparse-keymap)))
(define-key map "\C-c\C-c" 'image-toggle-display)
map)
"Major mode keymap for Image mode.")
"Major mode keymap for viewing images as text in Image mode.")
;;;###autoload
(defun image-mode ()
......@@ -58,13 +209,13 @@ to toggle between display as an image and display as text."
(kill-all-local-variables)
(setq mode-name "Image")
(setq major-mode 'image-mode)
(use-local-map image-mode-map)
(add-hook 'change-major-mode-hook 'image-toggle-display-text nil t)
(if (and (display-images-p)
(not (get-text-property (point-min) 'display)))
(image-toggle-display)
;; Set next vars when image is already displayed but local
;; variables were cleared by kill-all-local-variables
(use-local-map image-mode-map)
(setq cursor-type nil truncate-lines t))
(run-mode-hooks 'image-mode-hook)
(if (display-images-p)
......@@ -140,6 +291,8 @@ and showing the image as an image."
(set-buffer-modified-p modified)
(kill-local-variable 'cursor-type)
(kill-local-variable 'truncate-lines)
(kill-local-variable 'auto-hscroll-mode)
(use-local-map image-mode-text-map)
(if (called-interactively-p)
(message "Repeat this command to go back to displaying the image")))
;; Turn the image data into a real image, but only if the whole file
......@@ -161,12 +314,9 @@ and showing the image as an image."
nil t)))
(props
`(display ,image
intangible ,image
rear-nonsticky (display intangible)
;; This a cheap attempt to make the whole buffer
;; read-only when we're visiting the file (as
;; opposed to just inserting it).
read-only t front-sticky (read-only)))
intangible ,image
rear-nonsticky (display intangible)
read-only t front-sticky (read-only)))
(inhibit-read-only t)
(buffer-undo-list t)
(modified (buffer-modified-p)))
......@@ -179,6 +329,9 @@ and showing the image as an image."
;; 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)
;; Allow navigation of large images
(set (make-local-variable 'auto-hscroll-mode) nil)
(use-local-map image-mode-map)
(if (called-interactively-p)
(message "Repeat this command to go back to displaying the file as text")))))
......
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