Implement screen reader support using AccessKit library.

.github/workflows/linux_builds.yml

@@ -5,7 +5,7 @@ on:
 # Global Settings
 env:
   GODOT_CPP_BRANCH: 4.4
-  SCONSFLAGS: verbose=yes warnings=extra werror=yes module_text_server_fb_enabled=yes strict_checks=yes
+  SCONSFLAGS: verbose=yes warnings=extra werror=yes module_text_server_fb_enabled=yes strict_checks=yes "accesskit_sdk_path=${{ github.workspace }}/accesskit-c-0.15.1/"
   DOTNET_NOLOGO: true
   DOTNET_CLI_TELEMETRY_OPTOUT: true
   TSAN_OPTIONS: suppressions=${{ github.workspace }}/misc/error_suppressions/tsan.txt
@@ -151,6 +151,17 @@ jobs:
           # Targeting the oldest version we want to support to ensure it still builds.
           dotnet-version: 8.0.100
 
+      - name: Download pre-built AccessKit
+        uses: dsaltares/fetch-gh-release-asset@1.1.2
+        with:
+          repo: AccessKit/accesskit-c
+          version: tags/0.15.1
+          file: accesskit-c-0.15.1.zip
+          target: accesskit-c-0.15.1/accesskit_c.zip
+
+      - name: Extract pre-built AccessKit
+        run: unzip -o accesskit-c-0.15.1/accesskit_c.zip
+
       - name: Compilation
         uses: ./.github/actions/godot-build
         with:

.github/workflows/macos_builds.yml

@@ -4,7 +4,7 @@ on:
 
 # Global Settings
 env:
-  SCONSFLAGS: verbose=yes warnings=extra werror=yes module_text_server_fb_enabled=yes strict_checks=yes
+  SCONSFLAGS: verbose=yes warnings=extra werror=yes module_text_server_fb_enabled=yes strict_checks=yes "accesskit_sdk_path=${{ github.workspace }}/accesskit-c-0.15.1/"
 
 jobs:
   build-macos:
@@ -43,6 +43,17 @@ jobs:
       - name: Setup Python and SCons
         uses: ./.github/actions/godot-deps
 
+      - name: Download pre-built AccessKit
+        uses: dsaltares/fetch-gh-release-asset@1.1.2
+        with:
+          repo: AccessKit/accesskit-c
+          version: tags/0.15.1
+          file: accesskit-c-0.15.1.zip
+          target: accesskit-c-0.15.1/accesskit_c.zip
+
+      - name: Extract pre-built AccessKit
+        run: unzip -o accesskit-c-0.15.1/accesskit_c.zip
+
       - name: Setup Vulkan SDK
         id: vulkan-sdk
         run: |

.github/workflows/windows_builds.yml

@@ -5,7 +5,7 @@ on:
 # Global Settings
 # SCONS_CACHE for windows must be set in the build environment
 env:
-  SCONSFLAGS: verbose=yes warnings=extra werror=yes module_text_server_fb_enabled=yes d3d12=yes strict_checks=yes "angle_libs=${{ github.workspace }}/"
+  SCONSFLAGS: verbose=yes warnings=extra werror=yes module_text_server_fb_enabled=yes d3d12=yes strict_checks=yes "angle_libs=${{ github.workspace }}/" "accesskit_sdk_path=${{ github.workspace }}/accesskit-c-0.15.1/"
   SCONS_CACHE_MSVC_CONFIG: true
 
 jobs:
@@ -81,6 +81,17 @@ jobs:
       - name: Extract pre-built ANGLE static libraries
         run: Expand-Archive -Force angle/angle.zip ${{ github.workspace }}/
 
+      - name: Download pre-built AccessKit
+        uses: dsaltares/fetch-gh-release-asset@1.1.2
+        with:
+          repo: AccessKit/accesskit-c
+          version: tags/0.15.1
+          file: accesskit-c-0.15.1.zip
+          target: accesskit-c-0.15.1/accesskit_c.zip
+
+      - name: Extract pre-built AccessKit
+        run: unzip -o accesskit-c-0.15.1/accesskit_c.zip
+
       - name: Compilation
         uses: ./.github/actions/godot-build
         with:

.pre-commit-config.yaml

@@ -4,7 +4,7 @@ default_language_version:
 exclude: |
   (?x)^(
     .*thirdparty/.*|
-    .*-so_wrap\.(h|c)|
+    .*-(dll|dylib|so)_wrap\.[ch]|
     platform/android/java/editor/src/main/java/com/android/.*|
     platform/android/java/lib/src/com/google/.*
   )$

COPYRIGHT.txt

@@ -163,6 +163,11 @@ Comment: Temporal Anti-Aliasing resolve implementation
 Copyright: 2016, Panos Karabelas
 License: Expat
 
+Files: thirdparty/accesskit/*
+Comment: AccessKit
+Copyright: 2023, The AccessKit Authors.
+License: Expat
+
 Files: thirdparty/amd-fsr/*
 Comment: AMD FidelityFX Super Resolution
 Copyright: 2021, Advanced Micro Devices, Inc.

SConstruct

@@ -191,6 +191,8 @@ opts.Add(BoolVariable("use_volk", "Use the volk library to load the Vulkan loade
 opts.Add(BoolVariable("disable_exceptions", "Force disabling exception handling code", True))
 opts.Add("custom_modules", "A list of comma-separated directory paths containing custom modules to build.", "")
 opts.Add(BoolVariable("custom_modules_recursive", "Detect custom modules recursively for each specified path.", True))
+opts.Add(BoolVariable("accesskit", "Use AccessKit C SDK", True))
+opts.Add(("accesskit_sdk_path", "Path to the AccessKit C SDK", ""))
 
 # Advanced options
 opts.Add(

core/config/project_settings.cpp

@@ -1491,6 +1491,9 @@ ProjectSettings::ProjectSettings() {
 	GLOBAL_DEF("application/config/auto_accept_quit", true);
 	GLOBAL_DEF("application/config/quit_on_go_back", true);
 
+	GLOBAL_DEF_BASIC(PropertyInfo(Variant::INT, "accessibility/general/accessibility_support", PROPERTY_HINT_ENUM, "Auto (When Screen Reader is Running),Always Active,Disabled"), 0);
+	GLOBAL_DEF_BASIC(PropertyInfo(Variant::INT, "accessibility/general/updates_per_second", PROPERTY_HINT_RANGE, "1,100,1"), 60);
+
 	// The default window size is tuned to:
 	// - Have a 16:9 aspect ratio,
 	// - Have both dimensions divisible by 8 to better play along with video recording,

core/input/input_map.cpp

@@ -47,6 +47,8 @@ void InputMap::_bind_methods() {
 	ClassDB::bind_method(D_METHOD("add_action", "action", "deadzone"), &InputMap::add_action, DEFVAL(DEFAULT_DEADZONE));
 	ClassDB::bind_method(D_METHOD("erase_action", "action"), &InputMap::erase_action);
 
+	ClassDB::bind_method(D_METHOD("get_action_description", "action"), &InputMap::get_action_description);
+
 	ClassDB::bind_method(D_METHOD("action_set_deadzone", "action", "deadzone"), &InputMap::action_set_deadzone);
 	ClassDB::bind_method(D_METHOD("action_get_deadzone", "action"), &InputMap::action_get_deadzone);
 	ClassDB::bind_method(D_METHOD("action_add_event", "action", "event"), &InputMap::action_add_event);
@@ -181,6 +183,25 @@ bool InputMap::has_action(const StringName &p_action) const {
 	return input_map.has(p_action);
 }
 
+String InputMap::get_action_description(const StringName &p_action) const {
+	ERR_FAIL_COND_V_MSG(!input_map.has(p_action), String(), suggest_actions(p_action));
+
+	String ret;
+	const List<Ref<InputEvent>> &inputs = input_map[p_action].inputs;
+	for (Ref<InputEventKey> iek : inputs) {
+		if (iek.is_valid()) {
+			if (!ret.is_empty()) {
+				ret += RTR(" or ");
+			}
+			ret += iek->as_text();
+		}
+	}
+	if (ret.is_empty()) {
+		ret = RTR("Action has no bound inputs");
+	}
+	return ret;
+}
+
 float InputMap::action_get_deadzone(const StringName &p_action) {
 	ERR_FAIL_COND_V_MSG(!input_map.has(p_action), 0.0f, suggest_actions(p_action));
 
@@ -344,6 +365,7 @@ static const _BuiltinActionDisplayName _builtin_action_display_names[] = {
     { "ui_cut",                                        TTRC("Cut") },
     { "ui_copy",                                       TTRC("Copy") },
     { "ui_paste",                                      TTRC("Paste") },
+	{ "ui_focus_mode",                                 TTRC("Toggle Tab Focus Mode") },
     { "ui_undo",                                       TTRC("Undo") },
     { "ui_redo",                                       TTRC("Redo") },
     { "ui_text_completion_query",                      TTRC("Completion Query") },
@@ -397,12 +419,15 @@ static const _BuiltinActionDisplayName _builtin_action_display_names[] = {
     { "ui_text_submit",                                TTRC("Submit Text") },
     { "ui_graph_duplicate",                            TTRC("Duplicate Nodes") },
     { "ui_graph_delete",                               TTRC("Delete Nodes") },
+	{ "ui_graph_follow_left",                          TTRC("Follow Input Port Connection") },
+	{ "ui_graph_follow_right",                         TTRC("Follow Output Port Connection") },
     { "ui_filedialog_up_one_level",                    TTRC("Go Up One Level") },
     { "ui_filedialog_refresh",                         TTRC("Refresh") },
     { "ui_filedialog_show_hidden",                     TTRC("Show Hidden") },
     { "ui_swap_input_direction ",                      TTRC("Swap Input Direction") },
     { "ui_unicode_start",                              TTRC("Start Unicode Character Input") },
-    { "ui_colorpicker_delete_preset",               TTRC("Toggle License Notices") },
+    { "ui_colorpicker_delete_preset",                  TTRC("Toggle License Notices") },
+	{ "ui_accessibility_drag_and_drop",                TTRC("Accessibility: Keyboard Drag and Drop") },
     { "",                                              ""}
 	/* clang-format on */
 };
@@ -488,6 +513,9 @@ const HashMap<String, List<Ref<InputEvent>>> &InputMap::get_builtins() {
 	inputs.push_back(InputEventKey::create_reference(Key::END));
 	default_builtin_cache.insert("ui_end", inputs);
 
+	inputs = List<Ref<InputEvent>>();
+	default_builtin_cache.insert("ui_accessibility_drag_and_drop", inputs);
+
 	// ///// UI basic Shortcuts /////
 
 	inputs = List<Ref<InputEvent>>();
@@ -500,6 +528,10 @@ const HashMap<String, List<Ref<InputEvent>>> &InputMap::get_builtins() {
 	inputs.push_back(InputEventKey::create_reference(Key::INSERT | KeyModifierMask::CMD_OR_CTRL));
 	default_builtin_cache.insert("ui_copy", inputs);
 
+	inputs = List<Ref<InputEvent>>();
+	inputs.push_back(InputEventKey::create_reference(Key::M | KeyModifierMask::CTRL));
+	default_builtin_cache.insert("ui_focus_mode", inputs);
+
 	inputs = List<Ref<InputEvent>>();
 	inputs.push_back(InputEventKey::create_reference(Key::V | KeyModifierMask::CMD_OR_CTRL));
 	inputs.push_back(InputEventKey::create_reference(Key::INSERT | KeyModifierMask::SHIFT));
@@ -773,6 +805,22 @@ const HashMap<String, List<Ref<InputEvent>>> &InputMap::get_builtins() {
 	inputs.push_back(InputEventKey::create_reference(Key::KEY_DELETE));
 	default_builtin_cache.insert("ui_graph_delete", inputs);
 
+	inputs = List<Ref<InputEvent>>();
+	inputs.push_back(InputEventKey::create_reference(Key::LEFT | KeyModifierMask::CMD_OR_CTRL));
+	default_builtin_cache.insert("ui_graph_follow_left", inputs);
+
+	inputs = List<Ref<InputEvent>>();
+	inputs.push_back(InputEventKey::create_reference(Key::LEFT | KeyModifierMask::ALT));
+	default_builtin_cache.insert("ui_graph_follow_left.macos", inputs);
+
+	inputs = List<Ref<InputEvent>>();
+	inputs.push_back(InputEventKey::create_reference(Key::RIGHT | KeyModifierMask::CMD_OR_CTRL));
+	default_builtin_cache.insert("ui_graph_follow_right", inputs);
+
+	inputs = List<Ref<InputEvent>>();
+	inputs.push_back(InputEventKey::create_reference(Key::RIGHT | KeyModifierMask::ALT));
+	default_builtin_cache.insert("ui_graph_follow_right.macos", inputs);
+
 	// ///// UI File Dialog Shortcuts /////
 	inputs = List<Ref<InputEvent>>();
 	inputs.push_back(InputEventKey::create_reference(Key::BACKSPACE));

core/input/input_map.h

@@ -85,6 +85,8 @@ class InputMap : public Object {
 	void add_action(const StringName &p_action, float p_deadzone = DEFAULT_DEADZONE);
 	void erase_action(const StringName &p_action);
 
+	String get_action_description(const StringName &p_action) const;
+
 	float action_get_deadzone(const StringName &p_action);
 	void action_set_deadzone(const StringName &p_action, float p_deadzone);
 	void action_add_event(const StringName &p_action, const Ref<InputEvent> &p_event);

core/string/ustring.cpp

@@ -2073,34 +2073,45 @@ Error String::append_utf8(const char *p_utf8, int p_len, bool p_skip_cr) {
 	return result;
 }
 
-CharString String::utf8() const {
+CharString String::utf8(Vector<uint8_t> *r_ch_length_map) const {
 	int l = length();
 	if (!l) {
 		return CharString();
 	}
 
+	uint8_t *map_ptr = nullptr;
+	if (r_ch_length_map) {
+		r_ch_length_map->resize(l);
+		map_ptr = r_ch_length_map->ptrw();
+	}
+
 	const char32_t *d = &operator[](0);
 	int fl = 0;
 	for (int i = 0; i < l; i++) {
 		uint32_t c = d[i];
+		int ch_w = 1;
 		if (c <= 0x7f) { // 7 bits.
-			fl += 1;
+			ch_w = 1;
 		} else if (c <= 0x7ff) { // 11 bits
-			fl += 2;
+			ch_w = 2;
 		} else if (c <= 0xffff) { // 16 bits
-			fl += 3;
+			ch_w = 3;
 		} else if (c <= 0x001fffff) { // 21 bits
-			fl += 4;
+			ch_w = 4;
 		} else if (c <= 0x03ffffff) { // 26 bits
-			fl += 5;
+			ch_w = 5;
 			print_unicode_error(vformat("Invalid unicode codepoint (%x)", c));
 		} else if (c <= 0x7fffffff) { // 31 bits
-			fl += 6;
+			ch_w = 6;
 			print_unicode_error(vformat("Invalid unicode codepoint (%x)", c));
 		} else {
-			fl += 1;
+			ch_w = 1;
 			print_unicode_error(vformat("Invalid unicode codepoint (%x), cannot represent as UTF-8", c), true);
 		}
+		fl += ch_w;
+		if (map_ptr) {
+			map_ptr[i] = ch_w;
+		}
 	}
 
 	CharString utf8s;

core/string/ustring.h

@@ -511,7 +511,7 @@ class String {
 		return string;
 	}
 
-	CharString utf8() const;
+	CharString utf8(Vector<uint8_t> *r_ch_length_map = nullptr) const;
 	Error append_utf8(const char *p_utf8, int p_len = -1, bool p_skip_cr = false);
 	Error append_utf8(const Span<char> &p_range, bool p_skip_cr = false) {
 		return append_utf8(p_range.ptr(), p_range.size(), p_skip_cr);

doc/classes/Control.xml

@@ -24,13 +24,20 @@
 		<link title="All GUI Demos">https://github.com/godotengine/godot-demo-projects/tree/master/gui</link>
 	</tutorials>
 	<methods>
+		<method name="_accessibility_get_contextual_info" qualifiers="virtual const">
+			<return type="String" />
+			<description>
+				Return the description of the keyboard shortcuts and other contextual help for this control.
+			</description>
+		</method>
 		<method name="_can_drop_data" qualifiers="virtual const">
 			<return type="bool" />
 			<param index="0" name="at_position" type="Vector2" />
 			<param index="1" name="data" type="Variant" />
 			<description>
 				Godot calls this method to test if [param data] from a control's [method _get_drag_data] can be dropped at [param at_position]. [param at_position] is local to this control.
 				This method should only be used to test the data. Process the data in [method _drop_data].
+				[b]Note:[/b] If drag was initiated by keyboard shortcut or [method accessibility_drag], [param at_position] is set to [code]Vector2(INFINITY, INFINITY)[/code] and the currently selected item/text position should be used as drop position.
 				[codeblocks]
 				[gdscript]
 				func _can_drop_data(position, data):
@@ -55,6 +62,7 @@
 			<param index="1" name="data" type="Variant" />
 			<description>
 				Godot calls this method to pass you the [param data] from a control's [method _get_drag_data] result. Godot first calls [method _can_drop_data] to test if [param data] is allowed to drop at [param at_position] where [param at_position] is local to this control.
+				[b]Note:[/b] If drag was initiated by keyboard shortcut or [method accessibility_drag], [param at_position] is set to [code]Vector2(INFINITY, INFINITY)[/code] and the currently selected item/text position should be used as drop position.
 				[codeblocks]
 				[gdscript]
 				func _can_drop_data(position, data):
@@ -83,6 +91,7 @@
 			<description>
 				Godot calls this method to get data that can be dragged and dropped onto controls that expect drop data. Returns [code]null[/code] if there is no data to drag. Controls that want to receive drop data should implement [method _can_drop_data] and [method _drop_data]. [param at_position] is local to this control. Drag may be forced with [method force_drag].
 				A preview that will follow the mouse that should represent the data can be set with [method set_drag_preview]. A good time to set the preview is in this method.
+				[b]Note:[/b] If drag was initiated by keyboard shortcut or [method accessibility_drag], [param at_position] is set to [code]Vector2(INFINITY, INFINITY)[/code] and the currently selected item/text position should be used as drop position.
 				[codeblocks]
 				[gdscript]
 				func _get_drag_data(position):
@@ -223,6 +232,18 @@
 				[b]Note:[/b] This does not affect the methods in [Input], only the way events are propagated.
 			</description>
 		</method>
+		<method name="accessibility_drag">
+			<return type="void" />
+			<description>
+				Starts drag-and-drop operation without using a mouse.
+			</description>
+		</method>
+		<method name="accessibility_drop">
+			<return type="void" />
+			<description>
+				Ends drag-and-drop operation without using a mouse.
+			</description>
+		</method>
 		<method name="add_theme_color_override">
 			<return type="void" />
 			<param index="0" name="name" type="StringName" />
@@ -1174,6 +1195,9 @@
 		<constant name="FOCUS_ALL" value="2" enum="FocusMode">
 			The node can grab focus on mouse click, using the arrows and the Tab keys on the keyboard, or using the D-pad buttons on a gamepad. Use with [member focus_mode].
 		</constant>
+		<constant name="FOCUS_ACCESSIBILITY" value="3" enum="FocusMode">
+			The node can grab focus only when screen reader is active. Use with [member focus_mode].
+		</constant>
 		<constant name="RECURSIVE_BEHAVIOR_INHERITED" value="0" enum="RecursiveBehavior">
 			Inherits the associated behavior from the control's parent. This is the default for any newly created control.
 		</constant>