Port rumble support for SDL from moonlight-qt

src/connection.c

@@ -25,6 +25,7 @@
 
 pthread_t main_thread_id = 0;
 bool connection_debug;
+ConnListenerRumble rumble_handler = NULL;
 
 static void connection_terminated() {
   if (main_thread_id != 0)
@@ -46,6 +47,11 @@ static void connection_log_message(const char* format, ...) {
   va_end(arglist);
 }
 
+static void rumble(unsigned short controllerNumber, unsigned short lowFreqMotor, unsigned short highFreqMotor) {
+  if (rumble_handler)
+    rumble_handler(controllerNumber, lowFreqMotor, highFreqMotor);
+}
+
 CONNECTION_LISTENER_CALLBACKS connection_callbacks = {
   .stageStarting = NULL,
   .stageComplete = NULL,
@@ -55,4 +61,5 @@ CONNECTION_LISTENER_CALLBACKS connection_callbacks = {
   .displayMessage = connection_display_message,
   .displayTransientMessage = connection_display_transient_message,
   .logMessage = connection_log_message,
+  .rumble = rumble,
 };

src/connection.h

@@ -25,3 +25,4 @@
 extern CONNECTION_LISTENER_CALLBACKS connection_callbacks;
 extern pthread_t main_thread_id;
 extern bool connection_debug;
+extern ConnListenerRumble rumble_handler;

src/input/sdl.c

@@ -33,6 +33,8 @@ typedef struct _GAMEPAD_STATE {
   short rightStickX, rightStickY;
   int buttons;
   SDL_JoystickID sdl_id;
+  SDL_Haptic* haptic;
+  int haptic_effect_id;
   short id;
   bool initialized;
 } GAMEPAD_STATE, *PGAMEPAD_STATE;
@@ -44,22 +46,6 @@ static int activeGamepadMask = 0;
 
 int sdl_gamepads = 0;
 
-void sdlinput_init(char* mappings) {
-  memset(gamepads, 0, sizeof(gamepads));
-
-  SDL_InitSubSystem(SDL_INIT_GAMECONTROLLER);
-  SDL_GameControllerAddMappingsFromFile(mappings);
-
-  for (int i = 0; i < SDL_NumJoysticks(); ++i) {
-    if (SDL_IsGameController(i)) {
-      sdl_gamepads++;
-      if (!SDL_GameControllerOpen(i)) {
-        fprintf(stderr, "Could not open gamecontroller %i: %s\n", i, SDL_GetError());
-      }
-    }
-  }
-}
-
 static PGAMEPAD_STATE get_gamepad(SDL_JoystickID sdl_id) {
   for (int i = 0;i<4;i++) {
     if (!gamepads[i].initialized) {
@@ -74,6 +60,40 @@ static PGAMEPAD_STATE get_gamepad(SDL_JoystickID sdl_id) {
   return &gamepads[0];
 }
 
+static void init_gamepad(int joystick_index) {
+  if (SDL_IsGameController(joystick_index)) {
+    sdl_gamepads++;
+    SDL_GameController* controller = SDL_GameControllerOpen(joystick_index);
+    if (!controller) {
+      fprintf(stderr, "Could not open gamecontroller %i: %s\n", joystick_index, SDL_GetError());
+      return;
+    }
+
+    SDL_Joystick* joystick = SDL_GameControllerGetJoystick(controller);
+    SDL_Haptic* haptic = SDL_HapticOpenFromJoystick(joystick);
+    if (haptic && (SDL_HapticQuery(haptic) & SDL_HAPTIC_LEFTRIGHT) == 0) {
+      SDL_HapticClose(haptic);
+      haptic = NULL;
+    }
+
+    SDL_JoystickID sdl_id = SDL_JoystickInstanceID(joystick);
+    PGAMEPAD_STATE state = get_gamepad(joystick_index);
+    state->haptic = haptic;
+    state->haptic_effect_id = -1;
+  }
+}
+
+void sdlinput_init(char* mappings) {
+  memset(gamepads, 0, sizeof(gamepads));
+
+  SDL_InitSubSystem(SDL_INIT_GAMECONTROLLER);
+  SDL_InitSubSystem(SDL_INIT_HAPTIC);
+  SDL_GameControllerAddMappingsFromFile(mappings);
+
+  for (int i = 0; i < SDL_NumJoysticks(); ++i)
+    init_gamepad(i);
+}
+
 int sdlinput_handle_event(SDL_Event* event) {
   int button = 0;
   PGAMEPAD_STATE gamepad;
@@ -250,3 +270,33 @@ int sdlinput_handle_event(SDL_Event* event) {
   }
   return SDL_NOTHING;
 }
+
+void sdlinput_rumble(unsigned short controller_id, unsigned short low_freq_motor, unsigned short high_freq_motor) {
+  if (controller_id >= 4)
+    return;
+
+  PGAMEPAD_STATE state = &gamepads[controller_id];
+
+  SDL_Haptic* haptic = state->haptic;
+  if (!haptic)
+    return;
+
+  if (state->haptic_effect_id >= 0)
+    SDL_HapticDestroyEffect(haptic, state->haptic_effect_id);
+
+  if (low_freq_motor == 0 && high_freq_motor == 0)
+    return;
+
+  SDL_HapticEffect effect;
+  SDL_memset(&effect, 0, sizeof(effect));
+  effect.type = SDL_HAPTIC_LEFTRIGHT;
+  effect.leftright.length = SDL_HAPTIC_INFINITY;
+
+  // SDL haptics range from 0-32767 but XInput uses 0-65535, so divide by 2 to correct for SDL's scaling
+  effect.leftright.large_magnitude = low_freq_motor / 2;
+  effect.leftright.small_magnitude = high_freq_motor / 2;
+
+  state->haptic_effect_id = SDL_HapticNewEffect(haptic, &effect);
+  if (state->haptic_effect_id >= 0)
+    SDL_HapticRunEffect(haptic, state->haptic_effect_id, 1);
+}

src/input/sdl.h

@@ -101,3 +101,4 @@ static const short keyCodes5[] = {
 
 void sdlinput_init(char* mappings);
 int sdlinput_handle_event(SDL_Event* event);
+void sdlinput_rumble(unsigned short controller_id, unsigned short low_freq_motor, unsigned short high_freq_motor);

src/main.c

@@ -324,6 +324,7 @@ int main(int argc, char* argv[]) {
 
       sdl_init(config.stream.width, config.stream.height, config.fullscreen);
       sdlinput_init(config.mapping);
+      rumble_handler = sdlinput_rumble;
     }
     #endif