Merge pull request #990 from protocultor/old_sdl_gyro_switch

Gyro aiming for Switch controllers with SDL < 2.0.14

src/client/input/sdl.c

@@ -167,12 +167,25 @@ static qboolean gyro_active = false;
 
 // Gyro calibration
 static float gyro_accum[3];
-static unsigned int num_samples;
-
 static cvar_t *gyro_calibration_x;
 static cvar_t *gyro_calibration_y;
 static cvar_t *gyro_calibration_z;
 
+#if SDL_VERSION_ATLEAST(2, 0, 14)	// support for controller sensors (gyro, accelerometer)
+
+static unsigned int num_samples;
+#define NATIVE_SDL_GYRO	// uses SDL_CONTROLLERSENSORUPDATE to read gyro
+
+#else	// for SDL < 2.0.14, gyro can be read as a "secondary joystick" exposed by dkms-hid-nintendo
+
+static unsigned int num_samples[3];
+static SDL_Joystick *imu_joystick = NULL;	// gyro "joystick"
+#define IMU_JOY_AXIS_GYRO_ROLL 3
+#define IMU_JOY_AXIS_GYRO_PITCH 4
+#define IMU_JOY_AXIS_GYRO_YAW 5
+
+#endif
+
 // To ignore SDL_JOYDEVICEADDED at game init. Allows for hot plugging of game controller afterwards.
 static qboolean first_init = true;
 
@@ -766,7 +779,7 @@ IN_Update(void)
 				break;
 			}
 
-#if SDL_VERSION_ATLEAST(2, 0, 16)	// support for controller sensors (gyro, accelerometer)
+#ifdef NATIVE_SDL_GYRO	// controller sensors' reading supported (gyro, accelerometer)
 			case SDL_CONTROLLERSENSORUPDATE:
 				if (event.csensor.sensor != SDL_SENSOR_GYRO)
 				{
@@ -781,9 +794,39 @@ IN_Update(void)
 					break;
 				}
 
+#else	// gyro read as "secondary joystick"
+			case SDL_JOYAXISMOTION:
+				if ( !imu_joystick || event.cdevice.which != SDL_JoystickInstanceID(imu_joystick) )
+				{
+					break;	// controller axes handled by SDL_CONTROLLERAXISMOTION
+				}
+
+				int axis_value = event.caxis.value;
+				if (countdown_reason == REASON_GYROCALIBRATION && updates_countdown)
+				{
+					switch (event.caxis.axis)
+					{
+						case IMU_JOY_AXIS_GYRO_PITCH:
+							gyro_accum[0] += axis_value;
+							num_samples[0]++;
+							break;
+						case IMU_JOY_AXIS_GYRO_YAW:
+							gyro_accum[1] += axis_value;
+							num_samples[1]++;
+							break;
+						case IMU_JOY_AXIS_GYRO_ROLL:
+							gyro_accum[2] += axis_value;
+							num_samples[2]++;
+					}
+					break;
+				}
+
+#endif	// NATIVE_SDL_GYRO
+
 				if (gyro_active && gyro_mode->value &&
 					!cl_paused->value && cls.key_dest == key_game)
 				{
+#ifdef NATIVE_SDL_GYRO
 					if (!gyro_turning_axis->value)
 					{
 						gyro_yaw = event.csensor.data[1] - gyro_calibration_y->value;		// yaw
@@ -793,13 +836,31 @@ IN_Update(void)
 						gyro_yaw = -(event.csensor.data[2] - gyro_calibration_z->value);	// roll
 					}
 					gyro_pitch = event.csensor.data[0] - gyro_calibration_x->value;
+#else	// old "joystick" gyro
+					switch (event.caxis.axis)	// inside "case SDL_JOYAXISMOTION" here
+					{
+						case IMU_JOY_AXIS_GYRO_PITCH:
+							gyro_pitch = -(axis_value - gyro_calibration_x->value);
+							break;
+						case IMU_JOY_AXIS_GYRO_YAW:
+							if (!gyro_turning_axis->value)
+							{
+								gyro_yaw = axis_value - gyro_calibration_y->value;
+							}
+							break;
+						case IMU_JOY_AXIS_GYRO_ROLL:
+							if (gyro_turning_axis->value)
+							{
+								gyro_yaw = axis_value - gyro_calibration_z->value;
+							}
+					}
+#endif	// NATIVE_SDL_GYRO
 				}
 				else
 				{
 					gyro_yaw = gyro_pitch = 0;
 				}
 				break;
-#endif	// SDL_VERSION_ATLEAST(2, 0, 16)
 
 			case SDL_CONTROLLERDEVICEREMOVED:
 				if (!controller)
@@ -889,10 +950,23 @@ IN_Update(void)
 
 				case REASON_GYROCALIBRATION:	// finish and save calibration
 					{
+#ifdef NATIVE_SDL_GYRO
 						const float inverseSamples = 1.f / num_samples;
 						Cvar_SetValue("gyro_calibration_x", gyro_accum[0] * inverseSamples);
 						Cvar_SetValue("gyro_calibration_y", gyro_accum[1] * inverseSamples);
 						Cvar_SetValue("gyro_calibration_z", gyro_accum[2] * inverseSamples);
+#else
+						if (!num_samples[0] || !num_samples[1] || !num_samples[2])
+						{
+							Com_Printf("Calibration failed, please retry inside a level after having moved your controller a little.\n");
+						}
+						else
+						{
+							Cvar_SetValue("gyro_calibration_x", gyro_accum[0] / num_samples[0]);
+							Cvar_SetValue("gyro_calibration_y", gyro_accum[1] / num_samples[1]);
+							Cvar_SetValue("gyro_calibration_z", gyro_accum[2] / num_samples[2]);
+						}
+#endif
 						Com_Printf("Calibration results:\n X=%f Y=%f Z=%f\n",
 							gyro_calibration_x->value, gyro_calibration_y->value, gyro_calibration_z->value);
 						CalibrationFinishedCallback();
@@ -1269,7 +1343,11 @@ IN_Move(usercmd_t *cmd)
 	//
 	// For movement this is not needed, as those are absolute values independent of framerate
 	float joyViewFactor = cls.rframetime/0.01666f;
+#ifdef NATIVE_SDL_GYRO
 	float gyroViewFactor = (1.0f / M_PI) * joyViewFactor;
+#else
+	float gyroViewFactor = (1.0f / 2560.0f) * joyViewFactor;	// normalized for Switch gyro
+#endif
 
 	if (joystick_yaw)
 	{
@@ -1915,10 +1993,14 @@ Controller_Rumble(const char *name, vec3_t source, qboolean from_player,
 void
 StartCalibration(void)
 {
+#ifdef NATIVE_SDL_GYRO
+	num_samples = 0;
+#else
+	num_samples[0] = num_samples[1] = num_samples[2] = 0;
+#endif
 	gyro_accum[0] = 0.0;
 	gyro_accum[1] = 0.0;
 	gyro_accum[2] = 0.0;
-	num_samples = 0;
 	updates_countdown = 300;
 	countdown_reason = REASON_GYROCALIBRATION;
 }
@@ -2033,9 +2115,26 @@ IN_Controller_Init(qboolean notify_user)
 		// Ugly hack to detect IMU-only devices - works for Switch controllers at least
 		if (name_len > 4 && !strncmp(joystick_name + name_len - 4, " IMU", 4))
 		{
-			Com_Printf ("Skipping IMU device.\n");
 			SDL_JoystickClose(joystick);
 			joystick = NULL;
+#ifdef NATIVE_SDL_GYRO
+			Com_Printf ("Skipping IMU device.\n");
+#else	// if it's not a Left JoyCon, use it as Gyro
+			Com_Printf ("IMU device found.\n");
+			if ( !imu_joystick && name_len > 16 && strncmp(joystick_name + name_len - 16, "Left Joy-Con IMU", 16) != 0 )
+			{
+				imu_joystick = SDL_JoystickOpen(i);
+				if (imu_joystick)
+				{
+					show_gyro = true;
+					Com_Printf ("Using this device as Gyro sensor.\n");
+				}
+				else
+				{
+					Com_Printf ("Couldn't open IMU: %s.\n", SDL_GetError());
+				}
+			}
+#endif
 			continue;
 		}
 
@@ -2059,7 +2158,7 @@ IN_Controller_Init(qboolean notify_user)
 		SDL_JoystickClose(joystick);
 		joystick = NULL;
 
-		if (is_controller)
+		if (is_controller && !controller)
 		{
 			controller = SDL_GameControllerOpen(i);
 			if (!controller)
@@ -2071,7 +2170,7 @@ IN_Controller_Init(qboolean notify_user)
 			show_gamepad = true;
 			Com_Printf("Enabled as Game Controller, settings:\n%s\n", SDL_GameControllerMapping(controller));
 
-#if SDL_VERSION_ATLEAST(2, 0, 16)	// support for controller sensors
+#ifdef NATIVE_SDL_GYRO
 
 			if ( SDL_GameControllerHasSensor(controller, SDL_SENSOR_GYRO)
 				&& !SDL_GameControllerSetSensorEnabled(controller, SDL_SENSOR_GYRO, SDL_TRUE) )
@@ -2090,7 +2189,7 @@ IN_Controller_Init(qboolean notify_user)
 				SDL_GameControllerSetLED(controller, 0, 80, 0);	// green light
 			}
 
-#endif	// SDL_VERSION_ATLEAST(2, 0, 16)
+#endif	// NATIVE_SDL_GYRO
 
 			joystick_haptic = SDL_HapticOpenFromJoystick(SDL_GameControllerGetJoystick(controller));
 
@@ -2124,7 +2223,9 @@ IN_Controller_Init(qboolean notify_user)
 				Com_Printf("Controller doesn't support rumble.\n");
 			}
 
+#ifdef NATIVE_SDL_GYRO	// "native" exits when finding a single working controller
 			break;
+#endif
 		}
 	}
 }
@@ -2236,6 +2337,14 @@ IN_Controller_Shutdown(qboolean notify_user)
 	show_gamepad = show_gyro = show_haptic = false;
 	joystick_left_x = joystick_left_y = joystick_right_x = joystick_right_y = 0;
 	gyro_yaw = gyro_pitch = 0;
+
+#ifndef NATIVE_SDL_GYRO
+	if (imu_joystick)
+	{
+		SDL_JoystickClose(imu_joystick);
+		imu_joystick = NULL;
+	}
+#endif
 }
 
 /*