manual_control_setpoint: change stick axes naming

In review it was requested to have a different name for
manual_control_setpoint.z because of the adjusted range.

I started to investigate what naming is most intuitive and found
that most people recognize the stick axes as roll, pitch, yaw, throttle.
It comes at no surprise because other autopilots
and APIs seem to share this convention.

While changing the code I realized that even within the code base
the axes are usually assigned to a variable with that name or
have comments next to the assignment clarifying the axes
using these names.

src/modules/manual_control/ManualControl.cpp

@@ -162,10 +162,10 @@ void ManualControl::Run()
 		const float dt_s = (now - _last_time) / 1e6f;
 		const float minimum_stick_change = 0.01f * _param_com_rc_stick_ov.get();
 
-		_selector.setpoint().sticks_moving = (fabsf(_x_diff.update(_selector.setpoint().x, dt_s)) > minimum_stick_change)
-						     || (fabsf(_y_diff.update(_selector.setpoint().y, dt_s)) > minimum_stick_change)
-						     || (fabsf(_z_diff.update(_selector.setpoint().z, dt_s)) > minimum_stick_change)
-						     || (fabsf(_r_diff.update(_selector.setpoint().r, dt_s)) > minimum_stick_change);
+		_selector.setpoint().sticks_moving = (fabsf(_roll_diff.update(_selector.setpoint().roll, dt_s)) > minimum_stick_change)
+						     || (fabsf(_pitch_diff.update(_selector.setpoint().pitch, dt_s)) > minimum_stick_change)
+						     || (fabsf(_yaw_diff.update(_selector.setpoint().yaw, dt_s)) > minimum_stick_change)
+						     || (fabsf(_throttle_diff.update(_selector.setpoint().throttle, dt_s)) > minimum_stick_change);
 
 		if (switches_updated) {
 			// Only use switches if current source is RC as well.
@@ -310,10 +310,10 @@ void ManualControl::Run()
 			_manual_control_setpoint_pub.publish(_selector.setpoint());
 		}
 
-		_x_diff.reset();
-		_y_diff.reset();
-		_z_diff.reset();
-		_r_diff.reset();
+		_roll_diff.reset();
+		_pitch_diff.reset();
+		_yaw_diff.reset();
+		_throttle_diff.reset();
 		_stick_arm_hysteresis.set_state_and_update(false, now);
 		_stick_disarm_hysteresis.set_state_and_update(false, now);
 		_button_hysteresis.set_state_and_update(false, now);
@@ -330,8 +330,8 @@ void ManualControl::Run()
 void ManualControl::processStickArming(const manual_control_setpoint_s &input)
 {
 	// Arm gesture
-	const bool right_stick_centered = (fabsf(input.x) < 0.1f) && (fabsf(input.y) < 0.1f);
-	const bool left_stick_lower_right = (input.z < -0.8f) && (input.r > 0.9f);
+	const bool right_stick_centered = (fabsf(input.pitch) < 0.1f) && (fabsf(input.roll) < 0.1f);
+	const bool left_stick_lower_right = (input.throttle < -0.8f) && (input.yaw > 0.9f);
 
 	const bool previous_stick_arm_hysteresis = _stick_arm_hysteresis.get_state();
 	_stick_arm_hysteresis.set_state_and_update(left_stick_lower_right && right_stick_centered, input.timestamp);
@@ -341,7 +341,7 @@ void ManualControl::processStickArming(const manual_control_setpoint_s &input)
 	}
 
 	// Disarm gesture
-	const bool left_stick_lower_left = (input.z < -0.8f) && (input.r < -0.9f);
+	const bool left_stick_lower_left = (input.throttle < -0.8f) && (input.yaw < -0.9f);
 
 	const bool previous_stick_disarm_hysteresis = _stick_disarm_hysteresis.get_state();
 	_stick_disarm_hysteresis.set_state_and_update(left_stick_lower_left && right_stick_centered, input.timestamp);

src/modules/manual_control/ManualControl.hpp

@@ -117,10 +117,10 @@ private:
 	ManualControlSelector _selector;
 	bool _published_invalid_once{false};
 
-	MovingDiff _x_diff{};
-	MovingDiff _y_diff{};
-	MovingDiff _z_diff{};
-	MovingDiff _r_diff{};
+	MovingDiff _roll_diff{};
+	MovingDiff _pitch_diff{};
+	MovingDiff _yaw_diff{};
+	MovingDiff _throttle_diff{};
 
 	manual_control_switches_s _previous_switches{};
 	bool _previous_switches_initialized{false};