Fixed issues with displaying with org-tree-slide

ha-demos.org

@@ -2,7 +2,7 @@
 #+author: Howard X. Abrams
 #+date:   2024-10-18
 #+filetags: emacs hamacs
-#+lastmod: [2024-10-26 Sat]
+#+lastmod: [2024-10-30 Wed]
 
 A literate programming file for creating and running demonstrations
 
@@ -19,36 +19,57 @@ A literate programming file for creating and running demonstrations
   ;;
   ;; While obvious, GNU Emacs does not include this file or project.
   ;;
+  ;;; Commentary:
+  ;;
+  ;;  This replaces my original demo-it project encapsulating the following goals:
+  ;;
+  ;;  - Flexible presentation that can use either `org-present' or
+  ;;    continue to `org-tree-slide'
+  ;;
+  ;;  - Simpler support functions for showing side windows and whatnot
+  ;;
+  ;;  - Most importantly, a more flexible demonstration where trigger
+  ;;    events based on the current state.
+  ;;
   ;; *NB:* Do not edit this file. Instead, edit the original literate file at:
-  ;;            /Users/howard.abrams/src/hamacs/ha-demos.org
+  ;;            ~/src/hamacs/ha-demos.org
   ;;       And tangle the file to recreate this one.
   ;;
   ;;; Code:
 #+end_src
 
 * Introduction
-Once made demonstrations /within/ Emacs with my [[https://github.com/howardabrams/demo-it][demo-it]] project. While on MELPA, I wanted to use my own cloned version to make sure I can keep debugging it.
+Once I made demonstrations /within/ Emacs with my [[https://github.com/howardabrams/demo-it][demo-it]] project. While on MELPA, I wanted to use my own cloned version to make sure I can keep debugging it.
 
 #+begin_src emacs-lisp :tangle no
-  (use-package demo-it
+    (use-package demo-it
-    :straight (:local-repo "~/src/demo-it")
+      :straight (:local-repo "~/src/demo-it")
-    ;; :straight (:host github :repo "howardabrams/demo-it")
+      ;; :straight (:host github :repo "howardabrams/demo-it")
-    :commands (demo-it-create demo-it-start)
+      :commands (demo-it-create demo-it-start demo-it-hide-mode-line
-    :custom (demo-it--insert-test-speed :faster))
+                                demo-it--presentation-display-set)
+      :custom (demo-it--insert-test-speed :faster))
 #+end_src
 
-But I feel I should replace it.
+But I feel I should replace it, and this project encapsulates the following goals:
-* Presentations with Org
-Used to use [[https://github.com/takaxp/org-tree-slide][org-tree-slide]] for showing org files as presentations. Converted to use [[https://github.com/rlister/org-present][org-present]]. I love the /hooks/ as that makes it easier to handle. My concern with =org-present= is how it solely displays top-level headers.
 
-#+begin_src emacs-lisp
+  - Flexible presentation that can use either =org-present= or continue to =org-tree-slide=
+  - Simpler support functions for showing side windows and whatnot
+  - Most importantly, a more flexible demonstration where trigger events based on the current /state/.
+
+* Presentations with Org
+A demonstration begins with an Org file where the screen shows a /single heading/ with a larger font. Not much more. I have two projects that I like to use.
+** Org Present
+Converted to use [[https://github.com/rlister/org-present][org-present]]. I love the /hooks/ as that makes it easier to handle. My problem with =org-present= is that it doesn’t always display images.
+
+#+begin_src emacs-lisp :tangle no
   (use-package org-present
     :config
-    (defvar ha-org-present-mode-line mode-line-format "Cache previous mode-line format state")
+    (defvar ha-org-present-mode-line mode-line-format
+      "Cache previous mode-line format state")
 
     (defun ha-org-blocks-hide-headers ()
       "Make the headers and other block metadata invisible.
-      See `ha-org-blocks-show-headers'."
+        See `ha-org-blocks-show-headers'."
       (let ((pattern (rx bol (zero-or-more space)
                          (or ":" "#")
                          (zero-or-more any) eol)))
@@ -61,10 +82,12 @@ Used to use [[https://github.com/takaxp/org-tree-slide][org-tree-slide]] for sho
 
     (defun ha-org-blocks-show-headers ()
       "Un-invisibilize the headers and other block metadata invisible.
-      In other words, this undoes what `ha-org-blocks-hide-headers' did."
+    In other words, this undoes what `ha-org-blocks-hide-headers' did."
       (delete-all-overlays))
 
     (defun ha-org-present-start ()
+      "Hook to run when starting a presentation.
+    This happens _after_ `org-present' has started."
       (unless ha-org-present-mode-line
         (setq ha-org-present-mode-line mode-line-format))
       (goto-char (point-min)) (re-search-forward (rx bol "*"))
@@ -83,6 +106,9 @@ Used to use [[https://github.com/takaxp/org-tree-slide][org-tree-slide]] for sho
       (org-present-hide-cursor))
 
     (defun ha-org-present-end ()
+      "Hook to run when ending a presentation.
+    This happens _after_ `org-present-quit' has occurred,
+    and attempts to _undo_ effects of `ha-org-present-start'."
       (org-present-small)
       (org-present-read-write)
       (ha-org-blocks-show-headers)
@@ -90,9 +116,11 @@ Used to use [[https://github.com/takaxp/org-tree-slide][org-tree-slide]] for sho
       (jinx-mode) ; Turn on spell checking
       (org-present-show-cursor))
 
-    :hook
+    :bind
-    (org-present-mode . ha-org-present-start)
+    (:map org-tree-slide-mode-map
-    (org-present-mode-quit . ha-org-present-end)
+          ("<f5>" . org-present-next)
+          ("S-<f5>" . org-present-previous)
+          ("C-<f5>" . org-present-quit))
 
     :general
     (:states 'normal :keymaps 'org-present-mode-keymap
@@ -103,11 +131,78 @@ Used to use [[https://github.com/takaxp/org-tree-slide][org-tree-slide]] for sho
              "c" #'org-present-hide-cursor
              "C" #'org-present-show-cursor
              "n" #'org-present-next
+             "j" #'org-present-next
+             "k" #'org-present-prev
              "p" #'org-present-prev
              "r" #'org-present-read-only
              "w" #'org-present-read-write
-             "q" #'org-present-quit))
+             "q" #'org-present-quit)
+
+    :hook
+    (org-present-mode . ha-org-present-start)
+    (org-present-mode-quit . ha-org-present-end))
 #+end_src
+** Org Tree Slide
+I’ve used [[https://github.com/takaxp/org-tree-slide][org-tree-slide]] for years for showing org files as presentations. I like the /simple/ presentation and it seems to shows all the images.
+
+#+BEGIN_SRC emacs-lisp
+  (use-package org-tree-slide
+    :config
+    (setq org-tree-slide-heading-emphasis nil
+          org-tree-slide-activate-message "† This demonstration is running in Emacs"
+          org-tree-slide-cursor-init nil)
+    (org-tree-slide-simple-profile)
+
+    (defun ha-org-tree-slide-start ()
+      "Configure the presentation display.
+    See `ha-org-tree-slide-stop' that undoes this."
+      (setq org-hide-emphasis-markers t)
+      (set-face-attribute 'org-quote nil
+                          :inherit 'variable-pitch :slant 'italic)
+      (ha-demo-hide-cursor)
+      (ha-demo-presentation-frame)
+      (demo-it--presentation-display-set)
+      (ha-demo-hide-mode-line)
+      (git-gutter-mode -1)
+      (text-scale-set 4)
+      (flycheck-mode -1)
+      (jinx-mode -1))
+
+    (defun ha-org-tree-slide-stop ()
+      "Reset the display after a presentation.
+    See `ha-org-tree-slide-start' for what's set."
+      (demo-it--presentation-display-restore)  ; Restore previous changes
+      (setq org-hide-emphasis-markers t)
+      (ha-demo-show-mode-line)
+      (ha-demo-normalize-frame)
+      (ha-demo-show-cursor)
+      (git-gutter-mode)
+      (text-scale-set 0)
+      (flycheck-mode)
+      (jinx-mode))
+
+    :bind
+    (("S-<f6>" . org-tree-slide-skip-done-toggle)
+     :map org-tree-slide-mode-map
+     ("<f5>" . org-tree-slide-move-next-tree)
+     ("S-<f5>" . org-tree-slide-move-previous-tree)
+     ("M-<f5>" . org-tree-slide-content)
+     ("C-<f5>" . (lambda () (interactive) (org-tree-slide-mode -1))))
+
+    :general
+    (:states 'normal :keymaps 'org-tree-slide-mode-map
+             "c" #'ha-demo-hide-cursor
+             "C" #'ha-demo-show-cursor
+             "n" #'org-tree-slide-move-next-tree
+             "j" #'org-tree-slide-move-next-tree
+             "k" #'org-tree-slide-move-previous-tree
+             "p" #'org-tree-slide-move-previous-tree
+             "q" (lambda () (interactive) (org-slide-tree-mode -1)))
+
+    :hook
+    ((org-tree-slide-play . ha-org-tree-slide-start)
+     (org-tree-slide-stop . ha-org-tree-slide-stop)))
+#+END_SRC
 
 * New Demonstration
 Instead of executing a sequence of demonstration steps, demonstrations key on “state”, that is, the active buffer or major-mode, or the heading of an Org file, etc. I described the [[https://howardism.org/Technical/Emacs/demonstrations-part-two.html][guts of writing this code]], but we bind a key to calling =ha-demo-step= with a list of /state matchers/ to functions to call when matched. For instance:
@@ -118,9 +213,6 @@ Instead of executing a sequence of demonstration steps, demonstrations key on
                   (:heading "New Demonstration" :i 1) (message "Hi there"))
 
   (global-set-key (kbd "<f6>") 'ha-simple-demo)
-  (global-set-key (kbd "<f5>") 'org-present-next)
-  (global-set-key (kbd "S-<f5>") 'org-present-previous)
-  (global-set-key (kbd "C-<f5>") 'org-present-quit)
 #+END_SRC
 
 To make the contents of the expression easier to write, the =define-ha-demo= as a macro. Otherwise we write a complicated =cond= with lots of duplicated calls to =ha-demo-state-match= (defined later). This macro creates a function, so the first parameter is the name of the function:
@@ -242,6 +334,106 @@ Let’s create a function that could accept a list of /triggering keys/, and the
 * Demonstration Support
 What sort of functions will I often be doing?
 
+** Hide and Show the Cursor
+The typical presentation software has an issue for hiding the cursor when working with Evil mode, and since setting =cursor-type= to =nil= doesn’t work in a graphical display (where we typically run a presentation), the following functions turn on/off the displayed cursor.
+
+#+BEGIN_SRC emacs-lisp
+  (defvar ha-demo-cursor nil
+    "List of cursor states stored during `ha-demo-hide-cursor' and
+  restored with `ha-demo-show-cursor'.")
+
+  (defun ha-demo-hide-cursor ()
+    "Hide the cursor for the current frame."
+    (interactive)
+    (setq ha-demo-cursor
+          (list cursor-type
+                t ; (when (boundp 'evil-default-cursor) evil-default-cursor)
+                (when (boundp 'evil-emacs-state-cursor) evil-emacs-state-cursor)
+                (when (boundp 'evil-normal-state-cursor) evil-normal-state-cursor)
+                (default-value blink-cursor-mode)
+                (when (display-graphic-p)
+                  (frame-parameter (selected-frame) 'cursor-type))))
+
+    ;; Turn off the cursor blinking minor mode:
+    (blink-cursor-mode -1)
+
+    ;; Change the cursor types for normal and Evil states:
+    (setq-local cursor-type nil)
+    (when (boundp 'evil-default-cursor)
+      (setq-local
+       evil-default-cursor nil
+       evil-emacs-state-cursor nil
+       evil-normal-state-cursor nil))
+
+    ;; And most importantly, turn off the cursor for the selected frame:
+    (set-frame-parameter (selected-frame) 'cursor-type nil))
+
+  (defun ha-demo-show-cursor ()
+    "Restore cursor properties turned off by `ha-demo-hide-cursor'."
+    (interactive)
+    (setq cursor-type (car ha-demo-cursor))
+
+    (when (boundp 'evil-default-cursor)
+      (setq-local
+       evil-default-cursor (nth 1 ha-demo-cursor)
+       evil-emacs-state-cursor (nth 2 ha-demo-cursor)
+       evil-normal-state-cursor (nth 3 ha-demo-cursor)))
+
+    (when (nth 4 ha-demo-cursor) (blink-cursor-mode 1))
+
+    (set-frame-parameter (selected-frame)
+                         'cursor-type (nth 5 ha-demo-cursor)))
+    #+END_SRC
+
+** Hide and Show the Modeline
+For Org file displayed as presentations as well as images, we probably don’t want the distraction associated with the modeline, but when we finish the presentation, let’s turn it back on …
+
+#+BEGIN_SRC emacs-lisp
+  (defvar ha-demo-mode-line nil)
+  (make-variable-buffer-local 'ha-demo-mode-line)
+
+  (defun ha-demo-hide-mode-line ()
+    "Hide mode line for a particular buffer."
+    (interactive)
+    (when mode-line-format
+      (setq ha-demo-mode-line mode-line-format)
+      (setq mode-line-format nil)))
+
+  (defun ha-demo-show-mode-line ()
+    "Restore mode hidden with `ha-demo-hide-mode-line'."
+    (interactive)
+    (if ha-demo-mode-line
+        (setq mode-line-format ha-demo-mode-line)))
+    #+END_SRC
+
+** Presentation Frame Properties
+Like the work I’m doing to the mode-line, can we make the frame cleaner for a presentation?
+
+#+BEGIN_SRC emacs-lisp
+  (defvar ha-demo-frame-state nil
+    "Store frame properties during `ha-demo-presentation-frame' before
+  altering them, and then restore them with `ha-demo-normalize-frame'.")
+
+  (defun ha-demo-presentation-frame (&optional name)
+    "Remove the fringe and other frame settings.
+  See `ha-demo-normalize-frame' for restoration.
+  The NAME, if given, is the name of the frame."
+    (interactive)
+    (setq ha-demo-frame-state
+          (list
+           (frame-parameter (selected-frame) 'left-fringe)
+           (frame-parameter (selected-frame) 'right-fringe)))
+
+    (when name
+      (set-frame-parameter (selected-frame) 'name name)))
+
+  (defun ha-demo-normalize-frame ()
+    "Restore frame state from `ha-demo-presentation-frame'."
+    (interactive)
+    (set-frame-parameter (selected-frame) 'left-fringe (nth 0 ha-demo-frame-state))
+    (set-frame-parameter (selected-frame) 'right-fringe (nth 1 ha-demo-frame-state)))
+    #+END_SRC
+
 ** Display File
 Displaying a File with:
   - On the side or covering the entire frame