feat(org): add #+STARTUP inlinegifs playgifs

- #+STARTUP: inlinegifs = play inline gif previews when point is on
  them.
- #+STARTUP: playgifs = play all gifs in the visible buffer (super,
  super slow; use at your own risk).
- Add +org-startup-with-animated-gifs for changing the global
  default (nil). Can be set to 'at-point (inlinegifs) or t (playgifs)

modules/lang/org/autoload/org-link.el

@@ -84,6 +84,50 @@ exist, and `org-link' otherwise."
       (message "Download of image \"%s\" failed" link)
       nil)))
 
+(defvar +org--gif-timers nil)
+;;;###autoload
+(defun +org-play-gif-at-point-h ()
+  "Play the gif at point, while the cursor remains there (looping)."
+  (dolist (timer +org--gif-timers (setq +org--gif-timers nil))
+    (when (timerp (cdr timer))
+      (cancel-timer (cdr timer)))
+    (image-animate (car timer) nil 0))
+  (when-let* ((ov (cl-find-if
+                   (lambda (it) (overlay-get it 'org-image-overlay))
+                   (overlays-at (point))))
+              (dov (overlay-get ov 'display))
+              (pt  (point)))
+    (when (image-animated-p dov)
+      (push (cons
+             dov (run-with-idle-timer
+                  0.5 nil
+                  (lambda (dov)
+                    (when (equal
+                           ov (cl-find-if
+                               (lambda (it) (overlay-get it 'org-image-overlay))
+                               (overlays-at (point))))
+                      (message "playing gif")
+                      (image-animate dov nil t)))
+                  dov))
+            +org--gif-timers))))
+
+;;;###autoload
+(defun +org-play-all-gifs-h ()
+  "Continuously play all gifs in the visible buffer."
+  (dolist (ov (overlays-in (point-min) (point-max)))
+    (when-let* (((overlay-get ov 'org-image-overlay))
+                (dov (overlay-get ov 'display))
+                ((image-animated-p dov))
+                (w (selected-window)))
+      (while-no-input
+        (run-with-idle-timer
+         0.3 nil
+         (lambda (dov)
+           (when (pos-visible-in-window-p (overlay-start ov) w nil)
+             (unless (plist-get (cdr dov) :animate-buffer)
+               (image-animate dov))))
+         dov)))))
+
 
 ;;
 ;;; Commands
@@ -100,3 +144,13 @@ exist, and `org-link' otherwise."
                    (org-link-unescape (match-string-no-properties 1)))))
       (delete-region (match-beginning 0) (match-end 0))
       (insert label))))
+
+;;;###autoload
+(defun +org/play-gif-at-point ()
+  "TODO"
+  (interactive)
+  (unless (eq 'org-mode major-mode)
+    (user-error "Not in org-mode"))
+  (or (+org-play-gif-at-point-h)
+      (user-error "No gif at point")))
+

modules/lang/org/config.el

@@ -64,6 +64,9 @@ Is relative to `org-directory', unless it is absolute. Is used in Doom's default
 (defvar +org-habit-graph-window-ratio 0.3
   "The ratio of the consistency graphs relative to the window width")
 
+(defvar +org-startup-with-animated-gifs nil
+  "If non-nil, and the cursor is over a gif inline-image preview, animate it!")
+
 
 ;;
 ;;; `org-load' hooks
@@ -1250,4 +1253,17 @@ compelling reason, so..."
     :before-while '(org-id-locations-save org-id-locations-load)
     (file-writable-p org-id-locations-file))
 
-  (add-hook 'org-open-at-point-functions #'doom-set-jump-h))
+  (add-hook 'org-open-at-point-functions #'doom-set-jump-h)
+
+  ;; Add the ability to play gifs, at point or throughout the buffer. However,
+  ;; 'playgifs' is stupid slow and there's not much I can do to fix it; use at
+  ;; your own risk.
+  (add-to-list 'org-startup-options '("inlinegifs" +org-startup-with-animated-gifs at-point))
+  (add-to-list 'org-startup-options '("playgifs"   +org-startup-with-animated-gifs t))
+  (add-hook! 'org-mode-local-vars-hook
+    (defun +org-init-gifs-h ()
+      (remove-hook 'post-command-hook #'+org-play-gif-at-point-h t)
+      (remove-hook 'post-command-hook #'+org-play-all-gifs-h t)
+      (pcase +org-startup-with-animated-gifs
+        (`at-point (add-hook 'post-command-hook #'+org-play-gif-at-point-h nil t))
+        (`t (add-hook 'post-command-hook #'+org-play-all-gifs-h nil t))))))