Add support for SDL3 joystick input driver for the web platform (Emscripten)

doc/classes/Input.xml

@@ -130,14 +130,14 @@
 			<param index="0" name="device" type="int" />
 			<description>
 				Returns a dictionary with extra platform-specific information about the device, e.g. the raw gamepad name from the OS or the Steam Input index.
-				On Windows, Linux, and macOS, the dictionary contains the following fields:
+				On Windows, Linux, macOS, and Web, the dictionary contains the following fields:
 				[code]raw_name[/code]: The name of the controller as it came from the OS, before getting renamed by the controller database.
 				[code]vendor_id[/code]: The USB vendor ID of the device.
 				[code]product_id[/code]: The USB product ID of the device.
-				[code]steam_input_index[/code]: The Steam Input gamepad index, if the device is not a Steam Input device this key won't be present.
-				On Windows, the dictionary can have an additional field:
-				[code]xinput_index[/code]: The index of the controller in the XInput system. This key won't be present for devices not handled by XInput.
-				[b]Note:[/b] The returned dictionary is always empty on Android, iOS, visionOS, and Web.
+				The dictionary can also include the following fields under selected platforms:
+				[code]steam_input_index[/code]: The Steam Input gamepad index (Windows, Linux, and macOS only). If the device is not a Steam Input device this key won't be present.
+				[code]xinput_index[/code]: The index of the controller in the XInput system (Windows only). This key won't be present for devices not handled by XInput.
+				[b]Note:[/b] The returned dictionary is always empty on Android, iOS, and visionOS.
 			</description>
 		</method>
 		<method name="get_joy_name">

drivers/SCsub

@@ -61,8 +61,8 @@ if env["metal"]:
     SConscript("metal/SCsub")
 
 # Input drivers
-if env["sdl"] and env["platform"] in ["linuxbsd", "macos", "windows"]:
-    # TODO: Evaluate support for Android, iOS, and Web.
+if env["sdl"] and env["platform"] in ["linuxbsd", "macos", "windows", "web"]:
+    # TODO: Evaluate support for Android, iOS, and visionOS.
     SConscript("sdl/SCsub")
 
 # Core dependencies

drivers/sdl/SCsub

@@ -188,6 +188,23 @@ if env["builtin_sdl"]:
             "timer/windows/SDL_systimer.c",
         ]
 
+    elif env["platform"] == "web":
+        env_sdl.Append(CPPDEFINES=["SDL_PLATFORM_EMSCRIPTEN"])
+        thirdparty_sources += [
+            "core/unix/SDL_appid.c",
+            "core/unix/SDL_poll.c",
+            "haptic/dummy/SDL_syshaptic.c",
+            "joystick/emscripten/SDL_sysjoystick.c",
+            "loadso/dummy/SDL_sysloadso.c",
+            "thread/generic/SDL_syscond.c",
+            "thread/generic/SDL_sysmutex.c",
+            "thread/generic/SDL_sysrwlock.c",
+            "thread/generic/SDL_syssem.c",
+            "thread/generic/SDL_systhread.c",
+            "thread/generic/SDL_systls.c",
+            "timer/unix/SDL_systimer.c",
+        ]
+
     thirdparty_sources = [thirdparty_dir + file for file in thirdparty_sources]
 
     env_thirdparty = env_sdl.Clone()

drivers/sdl/SDL_build_config_private.h

@@ -132,6 +132,21 @@
 #define SDL_THREAD_PTHREAD 1
 #define SDL_THREAD_PTHREAD_RECURSIVE_MUTEX 1
 
+// Emscripten (web) defines
+#elif defined(SDL_PLATFORM_EMSCRIPTEN)
+
+#define SDL_PLATFORM_PRIVATE_NAME "Emscripten"
+#define SDL_PLATFORM_UNIX 1
+#define HAVE_STDIO_H 1
+#define HAVE_LIBC 1
+
+#define SDL_HAPTIC_DUMMY 1
+#define SDL_JOYSTICK_EMSCRIPTEN 1
+
+#define SDL_LOADSO_DUMMY 1
+#define SDL_THREADS_DISABLED 1
+#define SDL_TIMER_UNIX 1
+
 // Other platforms are not supported (for now)
 #else
 #error "No SDL build config was found for this platform. Setup one before compiling the engine."

drivers/sdl/joypad_sdl.cpp

@@ -43,6 +43,10 @@
 #include <SDL3/SDL_iostream.h>
 #include <SDL3/SDL_joystick.h>
 
+#ifdef WEB_ENABLED
+#include <emscripten/html5.h>
+#endif
+
 JoypadSDL *JoypadSDL::singleton = nullptr;
 
 // Macro to skip the SDL joystick event handling if the device is an SDL gamepad, because
@@ -172,13 +176,20 @@ void JoypadSDL::process_events() {
 
 				sdl_instance_id_to_joypad_id.insert(sdl_event.jdevice.which, joy_id);
 
+				if (should_ignore_joypad(sdl_event.jdevice.which)) {
+					close_joypad(joy_id);
+					continue;
+				}
+
 				Dictionary joypad_info;
 				// Skip Godot's mapping system if SDL already handles the joypad's mapping.
 				joypad_info["mapping_handled"] = SDL_IsGamepad(sdl_event.jdevice.which);
 				joypad_info["raw_name"] = String(SDL_GetJoystickName(joy));
 				joypad_info["vendor_id"] = itos(SDL_GetJoystickVendor(joy));
 				joypad_info["product_id"] = itos(SDL_GetJoystickProduct(joy));
 
+#if defined(WINDOWS_ENABLED) || defined(LINUXBSD_ENABLED) || defined(MACOS_ENABLED)
+				// These properties only make sense on desktop platforms.
 				const uint64_t steam_handle = SDL_GetGamepadSteamHandle(gamepad);
 				if (steam_handle != 0) {
 					joypad_info["steam_input_index"] = itos(steam_handle);
@@ -189,6 +200,7 @@ void JoypadSDL::process_events() {
 					// For XInput controllers SDL_GetJoystickPlayerIndex returns the XInput user index.
 					joypad_info["xinput_index"] = itos(player_index);
 				}
+#endif
 
 				Input::get_singleton()->joy_connection_changed(
 						joy_id,
@@ -197,7 +209,9 @@ void JoypadSDL::process_events() {
 						joypads[joy_id].guid,
 						joypad_info);
 
+#ifndef WEB_ENABLED // Joypad features are not supported on the web.
 				Input::get_singleton()->set_joy_features(joy_id, &joypads[joy_id]);
+#endif
 			}
 			// An event for an attached joypad
 		} else if (sdl_event.type >= SDL_EVENT_JOYSTICK_AXIS_MOTION && sdl_event.type < SDL_EVENT_FINGER_DOWN && sdl_instance_id_to_joypad_id.has(sdl_event.jdevice.which)) {
@@ -310,4 +324,20 @@ SDL_Gamepad *JoypadSDL::Joypad::get_sdl_gamepad() const {
 	return SDL_GetGamepadFromID(sdl_instance_idx);
 }
 
+bool JoypadSDL::should_ignore_joypad(SDL_JoystickID p_joy_id) {
+	SDL_Joystick *joy = SDL_GetJoystickFromID(p_joy_id);
+	String joy_name_lower = String(SDL_GetJoystickName(joy)).to_lower();
+
+#ifdef WEB_ENABLED
+	// DualSense on Firefox works very badly (input lag, no dpad, wrong face buttons, no vibration),
+	// I'm not sure it's fixable in Godot, so we just ignore it.
+	bool is_firefox = EM_ASM_INT({ return navigator.userAgent.toLowerCase().includes('firefox') });
+	if (is_firefox && joy_name_lower.contains("dualsense")) {
+		return true;
+	}
+#endif
+
+	return false;
+}
+
 #endif // SDL_ENABLED

drivers/sdl/joypad_sdl.h

@@ -71,4 +71,5 @@ class JoypadSDL {
 	HashMap<SDL_JoystickID, int> sdl_instance_id_to_joypad_id;
 
 	void close_joypad(int p_pad_idx);
+	bool should_ignore_joypad(SDL_JoystickID p_joy_id);
 };

platform/web/detect.py

@@ -309,6 +309,13 @@ def configure(env: "SConsEnvironment"):
     if env["wasm_simd"]:
         env.Append(CCFLAGS=["-msimd128"])
 
+    if env["sdl"]:
+        if env["builtin_sdl"]:
+            env.Append(CPPDEFINES=["SDL_ENABLED"])
+        else:
+            print_warning("`builtin_sdl` was explicitly disabled. Disabling SDL input driver support.")
+            env["sdl"] = False
+
     # Reduce code size by generating less support code (e.g. skip NodeJS support).
     env.Append(LINKFLAGS=["-sENVIRONMENT=web,worker"])
 

platform/web/display_server_web.cpp

@@ -837,36 +837,6 @@ void DisplayServerWeb::_window_blur_callback() {
 	Input::get_singleton()->release_pressed_events();
 }
 
-// Gamepad
-void DisplayServerWeb::gamepad_callback(int p_index, int p_connected, const char *p_id, const char *p_guid) {
-	String id = p_id;
-	String guid = p_guid;
-
-#ifdef PROXY_TO_PTHREAD_ENABLED
-	if (!Thread::is_main_thread()) {
-		callable_mp_static(DisplayServerWeb::_gamepad_callback).call_deferred(p_index, p_connected, id, guid);
-		return;
-	}
-#endif
-
-	_gamepad_callback(p_index, p_connected, id, guid);
-}
-
-void DisplayServerWeb::_gamepad_callback(int p_index, int p_connected, const String &p_id, const String &p_guid) {
-	if (p_connected) {
-		DisplayServerWeb::get_singleton()->gamepad_count += 1;
-	} else {
-		DisplayServerWeb::get_singleton()->gamepad_count -= 1;
-	}
-
-	Input *input = Input::get_singleton();
-	if (p_connected) {
-		input->joy_connection_changed(p_index, true, p_id, p_guid);
-	} else {
-		input->joy_connection_changed(p_index, false, "");
-	}
-}
-
 // IME.
 void DisplayServerWeb::ime_callback(int p_type, const char *p_text) {
 	String text = String::utf8(p_text);
@@ -964,36 +934,6 @@ String DisplayServerWeb::ime_get_text() const {
 	return ime_text;
 }
 
-void DisplayServerWeb::process_joypads() {
-	Input *input = Input::get_singleton();
-	int32_t pads = godot_js_input_gamepad_sample_count();
-	int32_t s_btns_num = 0;
-	int32_t s_axes_num = 0;
-	int32_t s_standard = 0;
-	float s_btns[16];
-	float s_axes[10];
-	for (int idx = 0; idx < pads; idx++) {
-		int err = godot_js_input_gamepad_sample_get(idx, s_btns, &s_btns_num, s_axes, &s_axes_num, &s_standard);
-		if (err) {
-			continue;
-		}
-		for (int b = 0; b < s_btns_num; b++) {
-			// Buttons 6 and 7 in the standard mapping need to be
-			// axis to be handled as JoyAxis::TRIGGER by Godot.
-			if (s_standard && (b == 6)) {
-				input->joy_axis(idx, JoyAxis::TRIGGER_LEFT, s_btns[b]);
-			} else if (s_standard && (b == 7)) {
-				input->joy_axis(idx, JoyAxis::TRIGGER_RIGHT, s_btns[b]);
-			} else {
-				input->joy_button(idx, (JoyButton)b, s_btns[b]);
-			}
-		}
-		for (int a = 0; a < s_axes_num; a++) {
-			input->joy_axis(idx, (JoyAxis)a, s_axes[a]);
-		}
-	}
-}
-
 Vector<String> DisplayServerWeb::get_rendering_drivers_func() {
 	Vector<String> drivers;
 #ifdef GLES3_ENABLED
@@ -1162,7 +1102,6 @@ DisplayServerWeb::DisplayServerWeb(const String &p_rendering_driver, WindowMode
 	godot_js_input_key_cb(&DisplayServerWeb::key_callback, key_event.code, key_event.key);
 	godot_js_input_paste_cb(&DisplayServerWeb::update_clipboard_callback);
 	godot_js_input_drop_files_cb(&DisplayServerWeb::drop_files_js_callback);
-	godot_js_input_gamepad_cb(&DisplayServerWeb::gamepad_callback);
 	godot_js_set_ime_cb(&DisplayServerWeb::ime_callback, &DisplayServerWeb::key_callback, key_event.code, key_event.key);
 
 	// JS Display interface (js/libs/library_godot_display.js)
@@ -1462,12 +1401,6 @@ DisplayServer::VSyncMode DisplayServerWeb::window_get_vsync_mode(WindowID p_vsyn
 void DisplayServerWeb::process_events() {
 	process_keys();
 	Input::get_singleton()->flush_buffered_events();
-
-	if (gamepad_count > 0) {
-		if (godot_js_input_gamepad_sample() == OK) {
-			process_joypads();
-		}
-	}
 }
 
 void DisplayServerWeb::process_keys() {

platform/web/display_server_web.h

@@ -104,8 +104,6 @@ class DisplayServerWeb : public DisplayServer {
 	bool swap_cancel_ok = false;
 	NativeMenu *native_menu = nullptr;
 
-	int gamepad_count = 0;
-
 	MouseMode mouse_mode_base = MOUSE_MODE_VISIBLE;
 	MouseMode mouse_mode_override = MOUSE_MODE_VISIBLE;
 	bool mouse_mode_override_enabled = false;
@@ -130,8 +128,6 @@ class DisplayServerWeb : public DisplayServer {
 	static void _key_callback(const String &p_key_event_code, const String &p_key_event_key, int p_pressed, int p_repeat, int p_modifiers);
 	WASM_EXPORT static void vk_input_text_callback(const char *p_text, int p_cursor);
 	static void _vk_input_text_callback(const String &p_text, int p_cursor);
-	WASM_EXPORT static void gamepad_callback(int p_index, int p_connected, const char *p_id, const char *p_guid);
-	static void _gamepad_callback(int p_index, int p_connected, const String &p_id, const String &p_guid);
 	WASM_EXPORT static void js_utterance_callback(int p_event, int64_t p_id, int p_pos);
 	static void _js_utterance_callback(int p_event, int64_t p_id, int p_pos);
 	WASM_EXPORT static void ime_callback(int p_type, const char *p_text);
@@ -149,7 +145,6 @@ class DisplayServerWeb : public DisplayServer {
 	WASM_EXPORT static void drop_files_js_callback(const char **p_filev, int p_filec);
 	static void _drop_files_js_callback(const Vector<String> &p_files);
 
-	void process_joypads();
 	void process_keys();
 
 	static Vector<String> get_rendering_drivers_func();

platform/web/godot_js.h

@@ -71,11 +71,6 @@ extern void godot_js_set_ime_position(int p_x, int p_y);
 extern void godot_js_set_ime_cb(void (*p_input)(int p_type, const char *p_text), void (*p_callback)(int p_type, int p_repeat, int p_modifiers), char r_code[32], char r_key[32]);
 extern int godot_js_is_ime_focused();
 
-// Input gamepad
-extern void godot_js_input_gamepad_cb(void (*p_on_change)(int p_index, int p_connected, const char *p_id, const char *p_guid));
-extern int godot_js_input_gamepad_sample();
-extern int godot_js_input_gamepad_sample_count();
-extern int godot_js_input_gamepad_sample_get(int p_idx, float r_btns[16], int32_t *r_btns_num, float r_axes[10], int32_t *r_axes_num, int32_t *r_standard);
 extern void godot_js_input_paste_cb(void (*p_callback)(const char *p_text));
 extern void godot_js_input_drop_files_cb(void (*p_callback)(const char **p_filev, int p_filec));