Files
emacs-doom/patches/0005-ns-integrate-accessibility-with-EmacsView-and-redisp.patch
Daneel 3bb6c989c9 patches: address maintainer review findings (C1/C2/H1/H2/M5/M6)
C1 - block_input ordering in ns_ax_buffer_text:
block_input() now called before record_unwind_protect_void(unblock_input).
Previously the unwind handler could have been called without a matching
block_input, corrupting the input-blocking reference count.

C2 - unbind_to missing in patch 0004:
unbind_to(blk_count, Qnil) moved from patch 0008 to patch 0004 so that
ns_ax_scan_interactive_spans has a complete block_input/unbind_to pair
when patches 0000-0004 are applied independently.

H1 - Zoom patch forward dependency on VoiceOver:
Removed forward declaration 'static bool ns_ax_face_is_selected' and
the delegation from ns_zoom_face_is_selected.  Restored standalone
implementation of ns_zoom_face_is_selected in the Zoom patch so patch
0000 compiles and links independently of the VoiceOver patches.

H2 - ns_accessibility_enabled removal undocumented:
Added comment to ns_zoom_track_completion explaining that Zoom cursor
tracking is gated only on ns_zoom_enabled_p(), not ns_accessibility_enabled.
Users running Zoom without VoiceOver must still get completion tracking.

M5 - childFrameLastBuffer GC safety undocumented:
Added comment at the assignment site explaining why BVAR(b, name) (an
interned symbol reachable from obarray) is GC-safe without staticpro.

M6 - FOR_EACH_FRAME without block_input:
Added block_input/unblock_input around the FOR_EACH_FRAME loop in
postAccessibilityUpdates that checks for visible child frames.
Vframe_list must not be modified by timers or process sentinels
during iteration.
2026-03-03 10:11:39 +01:00

628 lines
21 KiB
Diff

From 3a01e0c261a7ece2e8330dce32d4be6d5036be13 Mon Sep 17 00:00:00 2001
From: Martin Sukany <martin@sukany.cz>
Date: Sat, 28 Feb 2026 12:58:11 +0100
Subject: [PATCH 5/8] ns: integrate accessibility with EmacsView and redisplay
Wire the accessibility element tree into EmacsView and hook it into
the redisplay cycle.
* etc/NEWS: Document VoiceOver accessibility support.
* src/nsterm.m (ns_update_end): Call -[EmacsView postAccessibilityUpdates].
(EmacsApp ns_update_accessibility_state): New method; query
AXIsProcessTrustedWithOptions and UAZoomEnabled to set
ns_accessibility_enabled automatically.
(EmacsApp ns_accessibility_did_change:): New method; handle
com.apple.accessibility.api distributed notification.
(EmacsView dealloc): Release accessibilityElements.
(EmacsView windowDidBecomeKey:): Post accessibility focus notification.
(ns_ax_collect_windows): New function.
(EmacsView rebuildAccessibilityTree, invalidateAccessibilityTree)
(accessibilityChildren, accessibilityFocusedUIElement)
(postAccessibilityUpdates, accessibilityBoundsForRange:)
(accessibilityParameterizedAttributeNames)
(accessibilityAttributeValue:forParameter:): New methods.
---
etc/NEWS | 13 ++
src/nsterm.m | 474 +++++++++++++++++++++++++++++++++++++++++++++++++--
2 files changed, 475 insertions(+), 12 deletions(-)
diff --git a/etc/NEWS b/etc/NEWS
index 4c149e41d6..7f917f93b2 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -4385,6 +4385,19 @@ allowing Emacs users access to speech recognition utilities.
Note: Accepting this permission allows the use of system APIs, which may
send user data to Apple's speech recognition servers.
+---
+** VoiceOver accessibility support on macOS.
+Emacs now exposes buffer content, cursor position, and interactive
+elements to the macOS accessibility subsystem (VoiceOver). This
+includes AXBoundsForRange for macOS Zoom cursor tracking, line and
+word navigation announcements, Tab-navigable interactive spans
+(buttons, links, completion candidates), and completion announcements
+for the *Completions* buffer. The implementation uses a virtual
+accessibility tree with per-window elements, hybrid SelectedTextChanged
+and AnnouncementRequested notifications, and thread-safe text caching.
+Set 'ns-accessibility-enabled' to nil to disable the accessibility
+interface and eliminate the associated overhead.
+
---
** Re-introduced dictation, lost in Emacs v30 (macOS).
We lost macOS dictation in v30 when migrating to NSTextInputClient.
diff --git a/src/nsterm.m b/src/nsterm.m
index 8aa5b6ac1b..32eb04acef 100644
--- a/src/nsterm.m
+++ b/src/nsterm.m
@@ -1275,7 +1275,7 @@ If a completion candidate is selected (overlay or child frame),
static void
ns_zoom_track_completion (struct frame *f, EmacsView *view)
{
- if (!ns_zoom_enabled_p ())
+ if (!ns_accessibility_enabled || !ns_zoom_enabled_p ())
return;
if (!WINDOWP (f->selected_window))
return;
@@ -1393,7 +1393,8 @@ so the visual offset is (ov_line + 1) * line_h from
(zoomCursorUpdated is NO). */
#if defined (MAC_OS_X_VERSION_MIN_REQUIRED) \
&& MAC_OS_X_VERSION_MIN_REQUIRED >= 101000
- if (view && !view->zoomCursorUpdated && ns_zoom_enabled_p ()
+ if (ns_accessibility_enabled && view && !view->zoomCursorUpdated
+ && ns_zoom_enabled_p ()
&& !NSIsEmptyRect (view->lastCursorRect))
{
NSRect r = view->lastCursorRect;
@@ -1420,6 +1421,9 @@ so the visual offset is (ov_line + 1) * line_h from
if (view)
ns_zoom_track_completion (f, view);
#endif /* NS_IMPL_COCOA */
+
+ /* Post accessibility notifications after each redisplay cycle. */
+ [view postAccessibilityUpdates];
}
static void
@@ -3567,7 +3571,7 @@ EmacsView pixels (AppKit, flipped, top-left origin)
#if defined (MAC_OS_X_VERSION_MIN_REQUIRED) \
&& MAC_OS_X_VERSION_MIN_REQUIRED >= 101000
- if (ns_zoom_enabled_p ())
+ if (ns_accessibility_enabled && ns_zoom_enabled_p ())
{
NSRect windowRect = [view convertRect:r toView:nil];
NSRect screenRect
@@ -6723,9 +6727,56 @@ - (void)applicationDidFinishLaunching: (NSNotification *)notification
}
#endif
+#ifdef NS_IMPL_COCOA
+ /* Auto-detect Zoom and VoiceOver at startup and whenever their state
+ changes. The "com.apple.accessibility.api" distributed notification
+ fires when any assistive technology connects or disconnects.
+ Both code paths set ns_accessibility_enabled so that one variable
+ gates all our accessibility overhead. */
+ [self ns_update_accessibility_state];
+ [[NSDistributedNotificationCenter defaultCenter]
+ addObserver: self
+ selector: @selector(ns_accessibility_did_change:)
+ name: @"com.apple.accessibility.api"
+ object: nil
+suspensionBehavior: NSNotificationSuspensionBehaviorDeliverImmediately];
+#endif
+
ns_send_appdefined (-2);
}
+#ifdef NS_IMPL_COCOA
+/* Set ns_accessibility_enabled based on current AT state.
+ Called at startup and from the "com.apple.accessibility.api"
+ distributed notification handler. Checks both UAZoomEnabled()
+ (Zoom) and AXIsProcessTrustedWithOptions() (VoiceOver and other
+ ATs that have connected to this process). */
+- (void) ns_update_accessibility_state
+{
+ NSTRACE ("[EmacsApp ns_update_accessibility_state]");
+ BOOL zoom_on = UAZoomEnabled ();
+ NSDictionary *opts = @{(__bridge id) kAXTrustedCheckOptionPrompt: @NO};
+ BOOL at_on = AXIsProcessTrustedWithOptions ((__bridge CFDictionaryRef) opts);
+ BOOL new_state = zoom_on || at_on;
+ if ((BOOL) ns_accessibility_enabled != new_state)
+ {
+ ns_accessibility_enabled = new_state;
+ /* Reset the UAZoomEnabled cache so ns_zoom_enabled_p() reflects
+ the new Zoom state on its next call. */
+ ns_zoom_cache_time = 0;
+ }
+}
+
+/* Handler for the "com.apple.accessibility.api" distributed notification,
+ posted by macOS when any AT (VoiceOver, Switch Control, etc.) starts
+ or stops. */
+- (void) ns_accessibility_did_change: (NSNotification *) notification
+{
+ NSTRACE ("[EmacsApp ns_accessibility_did_change:]");
+ [self ns_update_accessibility_state];
+}
+#endif
+
- (void)antialiasThresholdDidChange:(NSNotification *)notification
{
#ifdef NS_IMPL_COCOA
@@ -7628,7 +7679,6 @@ - (id)accessibilityTopLevelUIElement
-
static BOOL
ns_ax_find_completion_overlay_range (struct buffer *b, ptrdiff_t point,
ptrdiff_t *out_start,
@@ -8741,7 +8791,6 @@ - (NSRect)accessibilityFrame
@end
-
/* ===================================================================
EmacsAccessibilityBuffer (Notifications) — AX event dispatch
@@ -9235,6 +9284,50 @@ - (void)postAccessibilityNotificationsForFrame:(struct frame *)f
granularity = ns_ax_text_selection_granularity_line;
}
+ /* Programmatic jumps that cross a line boundary (]], [[, M-<,
+ xref, imenu, …) are discontiguous: the cursor teleported to an
+ arbitrary position, not one sequential step forward/backward.
+ Reporting AXTextSelectionDirectionDiscontiguous causes VoiceOver
+ to re-anchor its rotor browse cursor at the new
+ accessibilitySelectedTextRange rather than advancing linearly
+ from its previous internal position. */
+ if (!isCtrlNP && granularity == ns_ax_text_selection_granularity_line)
+ direction = ns_ax_text_selection_direction_discontiguous;
+
+ /* If Emacs moved the cursor (not VoiceOver), force discontiguous
+ so VoiceOver re-anchors its browse cursor to the current
+ accessibilitySelectedTextRange. This covers all Emacs-initiated
+ moves: editing commands, ELisp, isearch, etc.
+ Exception: C-n/C-p (isCtrlNP) already uses next/previous with
+ line granularity; those are already sequential and VoiceOver
+ handles them correctly. */
+ if (emacsMovedCursor && !isCtrlNP)
+ direction = ns_ax_text_selection_direction_discontiguous;
+
+ /* Re-anchor VoiceOver's browse cursor for discontiguous (teleport)
+ moves only. For sequential C-n/C-p (isCtrlNP), posting
+ FocusedUIElementChanged on the window races with the
+ AXSelectedTextChanged(granularity=line) notification and
+ causes VoiceOver to drop the line-read speech. Sequential
+ moves are already handled correctly by AXSelectedTextChanged
+ with direction=next/previous + granularity=line. */
+ if (emacsMovedCursor && !isCtrlNP && [self isAccessibilityFocused])
+ {
+ NSWindow *win = [self.emacsView window];
+ if (win)
+ ns_ax_post_notification (
+ win,
+ NSAccessibilityFocusedUIElementChangedNotification);
+
+ NSDictionary *layoutInfo = @{
+ NSAccessibilityUIElementsKey: @[self]
+ };
+ ns_ax_post_notification_with_info (
+ self.emacsView,
+ NSAccessibilityLayoutChangedNotification,
+ layoutInfo);
+ }
+
/* Post notifications for focused and non-focused elements. */
if ([self isAccessibilityFocused])
[self postFocusedCursorNotification:point
@@ -9347,7 +9440,6 @@ - (NSRect)accessibilityFrame
@end
-
/* ===================================================================
EmacsAccessibilityInteractiveSpan --- helpers and implementation
=================================================================== */
@@ -9683,6 +9775,7 @@ - (void)dealloc
[layer release];
#endif
+ [accessibilityElements release];
[[self menu] release];
[super dealloc];
}
@@ -11031,6 +11124,32 @@ - (void)windowDidBecomeKey /* for direct calls */
XSETFRAME (event.frame_or_window, emacsframe);
kbd_buffer_store_event (&event);
ns_send_appdefined (-1); // Kick main loop
+
+#ifdef NS_IMPL_COCOA
+ /* Notify VoiceOver that the focused accessibility element changed.
+ Post on the focused virtual element so VoiceOver starts tracking it.
+ This is critical for initial focus and app-switch scenarios. */
+ if (ns_accessibility_enabled)
+ {
+ id focused = [self accessibilityFocusedUIElement];
+ if (focused
+ && [focused isKindOfClass:[EmacsAccessibilityBuffer class]])
+ {
+ ns_ax_post_notification (focused,
+ NSAccessibilityFocusedUIElementChangedNotification);
+ NSDictionary *info = @{
+ @"AXTextStateChangeType":
+ @(ns_ax_text_state_change_selection_move),
+ @"AXTextChangeElement": focused
+ };
+ ns_ax_post_notification_with_info (focused,
+ NSAccessibilitySelectedTextChangedNotification, info);
+ }
+ else if (focused)
+ ns_ax_post_notification (focused,
+ NSAccessibilityFocusedUIElementChangedNotification);
+ }
+#endif
}
@@ -12268,6 +12387,332 @@ - (int) fullscreenState
return fs_state;
}
+#ifdef NS_IMPL_COCOA
+
+/* ---- Accessibility: walk the Emacs window tree ---- */
+
+static void
+ns_ax_collect_windows (Lisp_Object window, EmacsView *view,
+ NSMutableArray *elements,
+ NSDictionary *existing)
+{
+ if (NILP (window))
+ return;
+
+ struct window *w = XWINDOW (window);
+
+ if (WINDOW_LEAF_P (w))
+ {
+ /* Buffer element — reuse existing if available. */
+ EmacsAccessibilityBuffer *elem
+ = [existing objectForKey:[NSValue valueWithPointer:w]];
+ if (!elem)
+ {
+ elem = [[EmacsAccessibilityBuffer alloc] init];
+ elem.emacsView = view;
+
+ /* Initialize cached state to -1 to force first notification. */
+ elem.cachedModiff = -1;
+ elem.cachedPoint = -1;
+ elem.cachedMarkActive = NO;
+ }
+ else
+ {
+ [elem retain];
+ }
+ elem.lispWindow = window;
+ [elements addObject:elem];
+ [elem release];
+
+ /* Mode line element (skip for minibuffer). */
+ if (!MINI_WINDOW_P (w))
+ {
+ EmacsAccessibilityModeLine *ml
+ = [[EmacsAccessibilityModeLine alloc] init];
+ ml.emacsView = view;
+ ml.lispWindow = window;
+ [elements addObject:ml];
+ [ml release];
+ }
+ }
+ else
+ {
+ /* Internal (combination) window — recurse into children. */
+ Lisp_Object child = w->contents;
+ while (!NILP (child))
+ {
+ ns_ax_collect_windows (child, view, elements, existing);
+ child = XWINDOW (child)->next;
+ }
+ }
+}
+
+- (void)rebuildAccessibilityTree
+{
+ NSTRACE ("[EmacsView rebuildAccessibilityTree]");
+ if (!emacsframe)
+ return;
+
+ /* Build map of existing elements by window pointer for reuse. */
+ NSMutableDictionary *existing = [NSMutableDictionary dictionary];
+ if (accessibilityElements)
+ {
+ for (EmacsAccessibilityElement *elem in accessibilityElements)
+ {
+ if ([elem isKindOfClass:[EmacsAccessibilityBuffer class]]
+ && !NILP (elem.lispWindow))
+ [existing setObject:elem
+ forKey:[NSValue valueWithPointer:
+ XWINDOW (elem.lispWindow)]];
+ }
+ }
+
+ NSMutableArray *newElements = [NSMutableArray arrayWithCapacity:8];
+
+ /* Collect from main window tree. */
+ Lisp_Object root = FRAME_ROOT_WINDOW (emacsframe);
+ ns_ax_collect_windows (root, self, newElements, existing);
+
+ /* Include minibuffer. */
+ Lisp_Object mini = emacsframe->minibuffer_window;
+ if (!NILP (mini))
+ ns_ax_collect_windows (mini, self, newElements, existing);
+
+ [accessibilityElements release];
+ accessibilityElements = [newElements retain];
+ accessibilityTreeValid = YES;
+}
+
+- (void)invalidateAccessibilityTree
+{
+ accessibilityTreeValid = NO;
+}
+
+- (NSAccessibilityRole)accessibilityRole
+{
+ return NSAccessibilityGroupRole;
+}
+
+- (NSString *)accessibilityLabel
+{
+ return @"Emacs";
+}
+
+- (BOOL)isAccessibilityElement
+{
+ return YES;
+}
+
+- (NSArray *)accessibilityChildren
+{
+ if (!accessibilityElements || !accessibilityTreeValid)
+ [self rebuildAccessibilityTree];
+ return accessibilityElements;
+}
+
+- (id)accessibilityFocusedUIElement
+{
+ if (!emacsframe)
+ return self;
+
+ if (!accessibilityElements || !accessibilityTreeValid)
+ [self rebuildAccessibilityTree];
+
+ for (EmacsAccessibilityElement *elem in accessibilityElements)
+ {
+ if ([elem isKindOfClass:[EmacsAccessibilityBuffer class]]
+ && EQ (elem.lispWindow, emacsframe->selected_window))
+ return elem;
+ }
+ return self;
+}
+
+/* Called from ns_update_end to post AX notifications.
+
+ Important: post notifications BEFORE rebuilding the tree.
+ The existing elements carry cached state (modiff, point) from the
+ previous redisplay cycle. Rebuilding first would create fresh
+ elements with current values, making change detection impossible. */
+- (void)postAccessibilityUpdates
+{
+ NSTRACE ("[EmacsView postAccessibilityUpdates]");
+ eassert ([NSThread isMainThread]);
+
+ if (!emacsframe || !ns_accessibility_enabled)
+ return;
+
+ /* Re-entrance guard: VoiceOver callbacks during notification posting
+ can trigger redisplay, which calls ns_update_end, which calls us
+ again. Prevent infinite recursion. */
+ if (accessibilityUpdating)
+ return;
+ accessibilityUpdating = YES;
+
+ /* Detect window tree change (split, delete, new buffer). Compare
+ FRAME_ROOT_WINDOW — if it changed, the tree structure changed. */
+ Lisp_Object curRoot = FRAME_ROOT_WINDOW (emacsframe);
+ if (!EQ (curRoot, lastRootWindow))
+ {
+ lastRootWindow = curRoot;
+ accessibilityTreeValid = NO;
+ }
+
+ /* If tree is stale, rebuild FIRST so we don't iterate freed
+ window pointers. Skip notifications for this cycle — the
+ freshly-built elements have no previous state to diff against. */
+ if (!accessibilityTreeValid)
+ {
+ [self rebuildAccessibilityTree];
+ /* Invalidate span cache — window layout changed. */
+ for (EmacsAccessibilityElement *elem in accessibilityElements)
+ if ([elem isKindOfClass: [EmacsAccessibilityBuffer class]])
+ [(EmacsAccessibilityBuffer *) elem invalidateInteractiveSpans];
+ ns_ax_post_notification (self,
+ NSAccessibilityLayoutChangedNotification);
+
+ /* Post focus change so VoiceOver picks up the new tree. */
+ id focused = [self accessibilityFocusedUIElement];
+ if (focused && focused != self)
+ ns_ax_post_notification (focused,
+ NSAccessibilityFocusedUIElementChangedNotification);
+
+ lastSelectedWindow = emacsframe->selected_window;
+ accessibilityUpdating = NO;
+ return;
+ }
+
+ /* Post per-buffer notifications using EXISTING elements that have
+ cached state from the previous cycle. Validate each window
+ pointer before use. */
+ for (EmacsAccessibilityElement *elem in accessibilityElements)
+ {
+ if ([elem isKindOfClass:[EmacsAccessibilityBuffer class]])
+ {
+ struct window *w = [elem validWindow];
+ if (w && WINDOW_LEAF_P (w)
+ && BUFFERP (w->contents) && XBUFFER (w->contents))
+ [(EmacsAccessibilityBuffer *) elem
+ postAccessibilityNotificationsForFrame:emacsframe];
+ }
+ }
+
+ /* Check for window switch (C-x o). */
+ Lisp_Object curSel = emacsframe->selected_window;
+ BOOL windowSwitched = !EQ (curSel, lastSelectedWindow);
+ if (windowSwitched)
+ {
+ lastSelectedWindow = curSel;
+ id focused = [self accessibilityFocusedUIElement];
+ if (focused && focused != self
+ && [focused isKindOfClass:[EmacsAccessibilityBuffer class]])
+ {
+ ns_ax_post_notification (focused,
+ NSAccessibilityFocusedUIElementChangedNotification);
+ NSDictionary *info = @{
+ @"AXTextStateChangeType":
+ @(ns_ax_text_state_change_selection_move),
+ @"AXTextChangeElement": focused
+ };
+ ns_ax_post_notification_with_info (focused,
+ NSAccessibilitySelectedTextChangedNotification, info);
+ }
+ else if (focused && focused != self)
+ ns_ax_post_notification (focused,
+ NSAccessibilityFocusedUIElementChangedNotification);
+ }
+
+ accessibilityUpdating = NO;
+}
+
+/* ---- Cursor position for Zoom (via accessibilityBoundsForRange:) ----
+
+ accessibilityFrame returns the VIEW's frame (standard behavior).
+ The cursor location is exposed through accessibilityBoundsForRange:
+ which AT tools query using the selectedTextRange. */
+
+- (NSRect)accessibilityBoundsForRange:(NSRange)range
+{
+ /* Delegate to the focused buffer element for accurate per-range
+ geometry when possible. Fall back to the cached cursor rect
+ (set by ns_draw_phys_cursor) for Zoom and simple AT queries. */
+ id focused = [self accessibilityFocusedUIElement];
+ if ([focused isKindOfClass:[EmacsAccessibilityBuffer class]])
+ {
+ NSRect bufRect = [(EmacsAccessibilityBuffer *) focused
+ accessibilityFrameForRange:range];
+ if (!NSIsEmptyRect (bufRect))
+ return bufRect;
+ }
+
+ NSRect viewRect = lastCursorRect;
+
+ if (viewRect.size.width < 1)
+ viewRect.size.width = 1;
+ if (viewRect.size.height < 1)
+ viewRect.size.height = 8;
+
+ NSWindow *win = [self window];
+ if (win == nil)
+ return NSZeroRect;
+
+ NSRect windowRect = [self convertRect:viewRect toView:nil];
+ return [win convertRectToScreen:windowRect];
+}
+
+/* Modern NSAccessibility protocol entry point. Delegates to
+ accessibilityBoundsForRange: which holds the real implementation
+ shared with the legacy parameterized-attribute API. */
+- (NSRect)accessibilityFrameForRange:(NSRange)range
+{
+ return [self accessibilityBoundsForRange:range];
+}
+
+/* Delegate to the focused virtual buffer element so both the modern
+ and legacy APIs return the correct string data. */
+- (NSString *)accessibilityStringForRange:(NSRange)range
+{
+ id focused = [self accessibilityFocusedUIElement];
+ if ([focused isKindOfClass:[EmacsAccessibilityBuffer class]])
+ return [(EmacsAccessibilityBuffer *) focused
+ accessibilityStringForRange:range];
+ return @"";
+}
+
+/* ---- Legacy parameterized attribute APIs (Zoom uses these) ---- */
+
+- (NSArray *)accessibilityParameterizedAttributeNames
+{
+ NSArray *superAttrs = [super accessibilityParameterizedAttributeNames];
+ if (superAttrs == nil)
+ superAttrs = @[];
+ return [superAttrs arrayByAddingObjectsFromArray:
+ @[NSAccessibilityBoundsForRangeParameterizedAttribute,
+ NSAccessibilityStringForRangeParameterizedAttribute]];
+}
+
+- (id)accessibilityAttributeValue:(NSString *)attribute
+ forParameter:(id)parameter
+{
+ if ([attribute isEqualToString:
+ NSAccessibilityBoundsForRangeParameterizedAttribute])
+ {
+ NSRange range = [(NSValue *) parameter rangeValue];
+ return [NSValue valueWithRect:
+ [self accessibilityBoundsForRange:range]];
+ }
+
+ if ([attribute isEqualToString:
+ NSAccessibilityStringForRangeParameterizedAttribute])
+ {
+ NSRange range = [(NSValue *) parameter rangeValue];
+ return [self accessibilityStringForRange:range];
+ }
+
+ return [super accessibilityAttributeValue:attribute forParameter:parameter];
+}
+
+#endif /* NS_IMPL_COCOA */
+
@end /* EmacsView */
@@ -14264,12 +14709,17 @@ Nil means use fullscreen the old (< 10.7) way. The old way works better with
ns_use_srgb_colorspace = YES;
DEFVAR_BOOL ("ns-accessibility-enabled", ns_accessibility_enabled,
- doc: /* Non-nil means expose buffer content to the macOS accessibility
-subsystem (VoiceOver, Zoom, and other assistive technology).
-When nil, the accessibility virtual element tree is not built and no
-notifications are posted, eliminating the associated overhead.
-Requires the Cocoa (NS) build on macOS; ignored on GNUstep.
-Default is nil. Set to t to enable VoiceOver support. */);
+ doc: /* Non-nil enables Zoom cursor tracking and VoiceOver support.
+Emacs sets this automatically at startup when macOS Zoom is active or
+any assistive technology (VoiceOver, Switch Control, etc.) is connected,
+and updates it whenever that state changes. You can override manually:
+
+ (setq ns-accessibility-enabled t) ; always on
+ (setq ns-accessibility-enabled nil) ; always off
+
+When nil, no AX tree is built and no notifications are posted,
+giving zero per-redisplay overhead.
+Requires the Cocoa (NS) build on macOS; ignored on GNUstep. */);
ns_accessibility_enabled = NO;
DEFVAR_BOOL ("ns-use-mwheel-acceleration",
--
2.43.0