SDL: Initial support for game controllers

The button mapping is that of the Vita port

Co-Authored-By: rsn8887 <rsn8887@users.noreply.github.com>

2 files changed, 212 insertions, 53 deletions

diff --git a/backends/events/sdl/sdl-events.cpp b/backends/events/sdl/sdl-events.cpp
index d01d9c6c4a..09530675c4 100644
--- a/backends/events/sdl/sdl-events.cpp
+++ b/backends/events/sdl/sdl-events.cpp
@@ -77,7 +77,7 @@ static uint32 convUTF8ToUTF32(const char *src) {
 SdlEventSource::SdlEventSource()
     : EventSource(), _scrollLock(false), _joystick(0), _lastScreenID(0), _graphicsManager(0), _queuedFakeMouseMove(false)
 #if SDL_VERSION_ATLEAST(2, 0, 0)
-      , _queuedFakeKeyUp(false), _fakeKeyUp()
+      , _queuedFakeKeyUp(false), _fakeKeyUp(), _controller(nullptr)
 #endif
       {
 	// Reset mouse state
@@ -90,16 +90,30 @@ SdlEventSource::SdlEventSource()
 			error("Could not initialize SDL: %s", SDL_GetError());
 		}
 
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+		if (SDL_InitSubSystem(SDL_INIT_GAMECONTROLLER) == -1) {
+			error("Could not initialize SDL: %s", SDL_GetError());
+		}
+#endif
+
 		// Enable joystick
 		if (SDL_NumJoysticks() > joystick_num) {
-			_joystick = SDL_JoystickOpen(joystick_num);
-			debug("Using joystick: %s",
 #if SDL_VERSION_ATLEAST(2, 0, 0)
-			      SDL_JoystickName(_joystick)
+			if (SDL_IsGameController(joystick_num)) {
+				_controller = SDL_GameControllerOpen(joystick_num);
+				debug("Using game controller: %s", SDL_GameControllerName(_controller));
+			} else
+#endif
+			{
+				_joystick = SDL_JoystickOpen(joystick_num);
+				debug("Using joystick: %s",
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+				      SDL_JoystickName(_joystick)
 #else
-			      SDL_JoystickName(joystick_num)
+				      SDL_JoystickName(joystick_num)
 #endif
-			     );
+				     );
+			}
 		} else {
 			warning("Invalid joystick: %d", joystick_num);
 		}
@@ -107,6 +121,10 @@ SdlEventSource::SdlEventSource()
 }
 
 SdlEventSource::~SdlEventSource() {
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+	if (_controller)
+		SDL_GameControllerClose(_controller);
+#endif
 	if (_joystick)
 		SDL_JoystickClose(_joystick);
 }
@@ -541,12 +559,6 @@ bool SdlEventSource::dispatchSDLEvent(SDL_Event &ev, Common::Event &event) {
 		return handleMouseButtonDown(ev, event);
 	case SDL_MOUSEBUTTONUP:
 		return handleMouseButtonUp(ev, event);
-	case SDL_JOYBUTTONDOWN:
-		return handleJoyButtonDown(ev, event);
-	case SDL_JOYBUTTONUP:
-		return handleJoyButtonUp(ev, event);
-	case SDL_JOYAXISMOTION:
-		return handleJoyAxisMotion(ev, event);
 
 #if SDL_VERSION_ATLEAST(2, 0, 0)
 	case SDL_MOUSEWHEEL: {
@@ -630,6 +642,30 @@ bool SdlEventSource::dispatchSDLEvent(SDL_Event &ev, Common::Event &event) {
 
 	}
 
+	if (_joystick) {
+		switch (ev.type) {
+		case SDL_JOYBUTTONDOWN:
+			return handleJoyButtonDown(ev, event);
+		case SDL_JOYBUTTONUP:
+			return handleJoyButtonUp(ev, event);
+		case SDL_JOYAXISMOTION:
+			return handleJoyAxisMotion(ev, event);
+		}
+	}
+
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+	if (_controller) {
+		switch (ev.type) {
+		case SDL_CONTROLLERBUTTONDOWN:
+			return handleControllerButton(ev, event, false);
+		case SDL_CONTROLLERBUTTONUP:
+			return handleControllerButton(ev, event, true);
+		case SDL_CONTROLLERAXISMOTION:
+			return handleControllerAxisMotion(ev, event);
+		}
+	}
+#endif
+
 	return false;
 }
 
@@ -867,70 +903,178 @@ bool SdlEventSource::handleJoyButtonUp(SDL_Event &ev, Common::Event &event) {
 }
 
 bool SdlEventSource::handleJoyAxisMotion(SDL_Event &ev, Common::Event &event) {
+	if (ev.jaxis.axis == JOY_XAXIS) {
+		_km.joy_x = ev.jaxis.value;
+		return handleAxisToMouseMotion(_km.joy_x, _km.joy_y);
+	} else if (ev.jaxis.axis == JOY_YAXIS) {
+		_km.joy_y = ev.jaxis.value;
+		return handleAxisToMouseMotion(_km.joy_x, _km.joy_y);
+	}
 
-	int axis = ev.jaxis.value;
-#ifdef JOY_ANALOG
-	// conversion factor between keyboard mouse and joy axis value
-	int vel_to_axis = (1500 / MULTIPLIER);
+	return false;
+}
+
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+bool SdlEventSource::handleControllerButton(const SDL_Event &ev, Common::Event &event, bool buttonUp) {
+	using namespace Common;
+
+	struct ControllerEventMapping {
+		EventType normalType;
+		KeyState normalKeystate;
+		EventType modifierType;
+		KeyState modifierKeystate;
+	};
+
+	static const ControllerEventMapping mapping[] = {
+			// SDL_CONTROLLER_BUTTON_A: Left mouse button
+			{ EVENT_LBUTTONDOWN, KeyState(), EVENT_LBUTTONDOWN, KeyState() },
+			// SDL_CONTROLLER_BUTTON_B: Right mouse button
+			{ EVENT_RBUTTONDOWN, KeyState(), EVENT_RBUTTONDOWN, KeyState() },
+			// SDL_CONTROLLER_BUTTON_X: Period (+R_trigger: Space)
+			{ EVENT_KEYDOWN, KeyState(KEYCODE_PERIOD, '.'), EVENT_KEYDOWN, KeyState(KEYCODE_SPACE, ASCII_SPACE) },
+			// SDL_CONTROLLER_BUTTON_Y: Escape (+R_trigger: Return)
+			{ EVENT_KEYDOWN, KeyState(KEYCODE_ESCAPE, ASCII_ESCAPE), EVENT_KEYDOWN, KeyState(KEYCODE_RETURN, ASCII_RETURN) },
+			// SDL_CONTROLLER_BUTTON_BACK: Virtual keyboard (+R_trigger: Predictive Input Dialog)
+#ifdef ENABLE_VKEYBD
+			{ EVENT_VIRTUAL_KEYBOARD, KeyState(), EVENT_PREDICTIVE_DIALOG, KeyState() },
 #else
-	if (axis > JOY_DEADZONE) {
-		axis -= JOY_DEADZONE;
-	} else if (axis < -JOY_DEADZONE) {
-		axis += JOY_DEADZONE;
-	} else
-		axis = 0;
+			{ EVENT_INVALID, KeyState(), EVENT_PREDICTIVE_DIALOG, KeyState() },
 #endif
+			// SDL_CONTROLLER_BUTTON_GUIDE: Unmapped
+			{ EVENT_INVALID, KeyState(), EVENT_INVALID, KeyState() },
+			// SDL_CONTROLLER_BUTTON_START: ScummVM in game menu
+			{ EVENT_MAINMENU, KeyState(), EVENT_MAINMENU, KeyState() },
+			// SDL_CONTROLLER_BUTTON_LEFTSTICK: Unmapped
+			{ EVENT_INVALID, KeyState(), EVENT_INVALID, KeyState() },
+			// SDL_CONTROLLER_BUTTON_RIGHTSTICK: Unmapped
+			{ EVENT_INVALID, KeyState(), EVENT_INVALID, KeyState() },
+			// SDL_CONTROLLER_BUTTON_LEFTSHOULDER: Game menu
+			{ EVENT_KEYDOWN, KeyState(KEYCODE_F5, ASCII_F5), EVENT_KEYDOWN, KeyState(KEYCODE_F5, ASCII_F5) },
+			// SDL_CONTROLLER_BUTTON_RIGHTSHOULDER: Modifier + Shift
+			{ EVENT_KEYDOWN, KeyState(KEYCODE_INVALID, 0, KBD_SHIFT), EVENT_KEYDOWN, KeyState(KEYCODE_INVALID, 0, 0) },
+			// SDL_CONTROLLER_BUTTON_DPAD_UP: Up (+R_trigger: Up+Right)
+			{ EVENT_KEYDOWN, KeyState(KEYCODE_KP8, 0), EVENT_KEYDOWN, KeyState(KEYCODE_KP9, 0) },
+			// SDL_CONTROLLER_BUTTON_DPAD_DOWN: Down (+R_trigger: Down+Left)
+			{ EVENT_KEYDOWN, KeyState(KEYCODE_KP2, 0), EVENT_KEYDOWN, KeyState(KEYCODE_KP1, 0) },
+			// SDL_CONTROLLER_BUTTON_DPAD_LEFT: Left (+R_trigger: Up+Left)
+			{ EVENT_KEYDOWN, KeyState(KEYCODE_KP4, 0), EVENT_KEYDOWN, KeyState(KEYCODE_KP7, 0) },
+			// SDL_CONTROLLER_BUTTON_DPAD_RIGHT: Right (+R_trigger: Down+Right)
+			{ EVENT_KEYDOWN, KeyState(KEYCODE_KP6, 0), EVENT_KEYDOWN, KeyState(KEYCODE_KP3, 0) }
+	};
+
+	if (ev.cbutton.button > SDL_CONTROLLER_BUTTON_DPAD_RIGHT) {
+		warning("Unknown SDL controller button: '%d'", ev.cbutton.button);
+		return false;
+	}
 
-	if (ev.jaxis.axis == JOY_XAXIS) {
-#ifdef JOY_ANALOG
-		_km.joy_x = axis;
-#else
-		if (axis != 0) {
-			_km.x_vel = (axis > 0) ? 1 * MULTIPLIER:-1 * MULTIPLIER;
-			_km.x_down_count = 1;
+	if (!_km.modifier) {
+		event.type = mapping[ev.cbutton.button].normalType;
+		event.kbd = mapping[ev.cbutton.button].normalKeystate;
+	} else {
+		event.type = mapping[ev.cbutton.button].modifierType;
+		event.kbd = mapping[ev.cbutton.button].modifierKeystate;
+	}
+
+	// Setting the mouse speed modifier after filling the event structure above
+	// ensures that the shift key events are correctly handled
+	if (ev.cbutton.button == SDL_CONTROLLER_BUTTON_RIGHTSHOULDER) {
+		// Right shoulder is the modifier button that makes the mouse go slower
+		// and allows access to an extended layout while pressed.
+		_km.modifier = !buttonUp;
+	}
+
+	if (event.type == EVENT_LBUTTONDOWN || event.type == EVENT_RBUTTONDOWN) {
+		processMouseEvent(event, _km.x / MULTIPLIER, _km.y / MULTIPLIER);
+	}
+
+	if (buttonUp) {
+		// The event mapping table is for button down events. If we received a button up event,
+		// transform the event type to the corresponding up type.
+		if (event.type == EVENT_KEYDOWN) {
+			event.type = EVENT_KEYUP;
+		} else if (event.type == EVENT_LBUTTONDOWN) {
+			event.type = EVENT_LBUTTONUP;
+		} else if (event.type == EVENT_RBUTTONDOWN) {
+			event.type = EVENT_RBUTTONUP;
 		} else {
-			_km.x_vel = 0;
-			_km.x_down_count = 0;
+			// Handled in key down
+			event.type = EVENT_INVALID;
 		}
+	}
+
+	return event.type != EVENT_INVALID;
+}
+
+bool SdlEventSource::handleControllerAxisMotion(const SDL_Event &ev, Common::Event &event) {
+	if (ev.caxis.axis == SDL_CONTROLLER_AXIS_LEFTX) {
+		_km.joy_x = ev.caxis.value;
+		return handleAxisToMouseMotion(_km.joy_x, _km.joy_y);
+	} else if (ev.caxis.axis == SDL_CONTROLLER_AXIS_LEFTY) {
+		_km.joy_y = ev.caxis.value;
+		return handleAxisToMouseMotion(_km.joy_x, _km.joy_y);
+	}
+
+	return false;
+}
 #endif
-	} else if (ev.jaxis.axis == JOY_YAXIS) {
-#ifndef JOY_INVERT_Y
-		axis = -axis;
-#endif
-#ifdef JOY_ANALOG
-		_km.joy_y = -axis;
-#else
-		if (axis != 0) {
-			_km.y_vel = (-axis > 0) ? 1 * MULTIPLIER: -1 * MULTIPLIER;
-			_km.y_down_count = 1;
-		} else {
-			_km.y_vel = 0;
-			_km.y_down_count = 0;
-		}
+
+bool SdlEventSource::handleAxisToMouseMotion(int16 xAxis, int16 yAxis) {
+#ifdef JOY_INVERT_Y
+	yAxis = -yAxis;
 #endif
-	}
+
 #ifdef JOY_ANALOG
-	// radial and scaled analog joystick deadzone
-	float analogX = (float)_km.joy_x;
-	float analogY = (float)_km.joy_y;
+	// conversion factor between keyboard mouse and joy axis value
+	int vel_to_axis = (1500 / MULTIPLIER);
+
+	// radial and scaled deadzone
+
+	float analogX = (float)xAxis;
+	float analogY = (float)yAxis;
 	float deadZone = (float)JOY_DEADZONE;
 	if (g_system->hasFeature(OSystem::kFeatureJoystickDeadzone))
 		deadZone = (float)ConfMan.getInt("joystick_deadzone") * 1000.0f;
-	float scalingFactor = 1.0f;
-	float magnitude = 0.0f;
 
-	magnitude = sqrt(analogX * analogX + analogY * analogY);
+	float magnitude = sqrt(analogX * analogX + analogY * analogY);
 
 	if (magnitude >= deadZone) {
 		_km.x_down_count = 0;
 		_km.y_down_count = 0;
-		scalingFactor = 1.0f / magnitude * (magnitude - deadZone) / (32769.0f - deadZone);
+		float scalingFactor = 1.0f / magnitude * (magnitude - deadZone) / (32769.0f - deadZone);
 		_km.x_vel = (int16)(analogX * scalingFactor * 32768.0f / vel_to_axis);
 		_km.y_vel = (int16)(analogY * scalingFactor * 32768.0f / vel_to_axis);
 	} else {
 		_km.x_vel = 0;
 		_km.y_vel = 0;
 	}
+#else
+	if (xAxis > JOY_DEADZONE) {
+		xAxis -= JOY_DEADZONE;
+	} else if (xAxis < -JOY_DEADZONE) {
+		xAxis += JOY_DEADZONE;
+	} else
+		xAxis = 0;
+	if (yAxis > JOY_DEADZONE) {
+		yAxis -= JOY_DEADZONE;
+	} else if (yAxis < -JOY_DEADZONE) {
+		yAxis += JOY_DEADZONE;
+	} else
+		yAxis = 0;
+
+	if (xAxis != 0) {
+		_km.x_vel = (xAxis > 0) ? 1 * MULTIPLIER:-1 * MULTIPLIER;
+		_km.x_down_count = 1;
+	} else {
+		_km.x_vel = 0;
+		_km.x_down_count = 0;
+	}
+	if (yAxis != 0) {
+		_km.y_vel = (yAxis > 0) ? 1 * MULTIPLIER: -1 * MULTIPLIER;
+		_km.y_down_count = 1;
+	} else {
+		_km.y_vel = 0;
+		_km.y_down_count = 0;
+	}
 #endif
 
 	return false;
diff --git a/backends/events/sdl/sdl-events.h b/backends/events/sdl/sdl-events.h
index 5fd3cb7ea5..cea944fb1a 100644
--- a/backends/events/sdl/sdl-events.h
+++ b/backends/events/sdl/sdl-events.h
@@ -80,6 +80,11 @@ protected:
 	/** Joystick */
 	SDL_Joystick *_joystick;
 
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+	/** Game controller */
+	SDL_GameController *_controller;
+#endif
+
 	/** Last screen id for checking if it was modified */
 	int _lastScreenID;
 
@@ -117,9 +122,19 @@ protected:
 	virtual bool handleJoyAxisMotion(SDL_Event &ev, Common::Event &event);
 	virtual bool handleKbdMouse(Common::Event &event);
 
+#if SDL_VERSION_ATLEAST(2, 0, 0)
+	virtual bool handleControllerButton(const SDL_Event &ev, Common::Event &event, bool buttonUp);
+	virtual bool handleControllerAxisMotion(const SDL_Event &ev, Common::Event &event);
+#endif
+
 	//@}
 
 	/**
+	 * Update the virtual mouse according to a joystick or game controller axis position change
+	 */
+	bool handleAxisToMouseMotion(int16 xAxis, int16 yAxis);
+
+	/**
 	 * Assigns the mouse coords to the mouse event. Furthermore notify the
 	 * graphics manager about the position change.
 	 */