Maintain tracker correction until it times out

README.md

@@ -57,7 +57,6 @@ scons platform=windows use_mingw=yes use_llvm=yes
 
 ## Roadmap
 
-- When having a short tracker interruption, maintain it in the same position until it times out to minimize the viewport jumps
 - Try to have some acceptable setup for Varjo even without the tracker
 - Rework the fly area
   - Make it bigger

project/aircraft/aircraft.gd

@@ -19,42 +19,47 @@ var _rotor_azimuth: float = 0
 @onready var xr_origin: XROrigin3D = $AttitudeRoot/PilotEyes/PilotFloor/XROrigin3D
 @onready var tracker: XRController3D = $AttitudeRoot/PilotEyes/PilotFloor/XROrigin3D/ViveTracker
 @onready var xr_camera: XRCamera3D = $AttitudeRoot/PilotEyes/PilotFloor/XROrigin3D/XRCamera3D
+@onready var recent_tracking: Timer = $AttitudeRoot/PilotEyes/PilotFloor/XROrigin3D/RecentTracking
 
 @onready var bone_cg: int = skeleton.find_bone("BodyCG")
 @onready var bone_cyclic: int = skeleton.find_bone("Cyclic")
 @onready var bone_rotor: int = skeleton.find_bone("Rotor")
 
 func _process(delta: float) -> void:
-	var target := connector.get_aircraft()
+	var target: Transform3D = connector.get_aircraft()
 	position = target.origin
 
 	# Add the rotation to the correct bone for rotation around CG
-	var rest := skeleton.get_bone_rest(bone_cg).basis.get_rotation_quaternion()
+	var rest: Quaternion = skeleton.get_bone_rest(bone_cg).basis.get_rotation_quaternion()
-	var attitude := target.basis.get_rotation_quaternion()
+	var attitude: Quaternion = target.basis.get_rotation_quaternion()
 	skeleton.set_bone_pose_rotation(bone_cg, attitude * rest)
 
 	# Rotate other children (not using BoneAttachment3D due to jitter)
 	attitude_root.rotation = target.basis.get_euler()
 
 	# Rotate the cyclic stick bone
-	var cyclic := connector.get_cyclic()
+	var cyclic: Vector2 = connector.get_cyclic()
-	var cyc_rest := skeleton.get_bone_rest(bone_cyclic).basis.get_rotation_quaternion()
+	var cyc_rest: Quaternion= skeleton.get_bone_rest(bone_cyclic).basis.get_rotation_quaternion()
-	var cyc_angles_rad := cyclic * deg_to_rad(range_cyclic)
+	var cyc_angles_rad: Vector2 = cyclic * deg_to_rad(range_cyclic)
 	var cyc_att := Quaternion.from_euler(Vector3(cyc_angles_rad.y, cyc_angles_rad.x, 0))
 	skeleton.set_bone_pose_rotation(bone_cyclic, cyc_att * cyc_rest)
 
 	# Spin the rotor only when receiving flight data
 	if connector.get_model_connected():
 		_rotor_azimuth += rotor_rpm * 2 * PI / 60 * delta
-		var rotor_rest := skeleton.get_bone_rest(bone_rotor).basis.get_rotation_quaternion()
+		var rotor_rest: Quaternion = skeleton.get_bone_rest(bone_rotor).basis.get_rotation_quaternion()
 		var rotor_att := Quaternion.from_euler(Vector3(0, _rotor_azimuth, 0))
 		# Note that this is reverse order, to rotate in local bone axes
 		skeleton.set_bone_pose_rotation(bone_rotor, rotor_rest * rotor_att)
 
+	# Move the XR origin in such way that the tracker is in reference position
 	if tracker.get_has_tracking_data():
-		var tracker_mount = tracker_mount_platform if track_platform else tracker_mount_chair
+		var tracker_mount: Node3D = tracker_mount_platform if track_platform else tracker_mount_chair
 		xr_origin.transform = tracker_mount.transform * tracker.transform.affine_inverse()
-	else:
+		recent_tracking.start()
+
+# Only reset the position when tracking is lost for some time
+func _on_recent_tracking_timeout() -> void:
 	xr_origin.transform = Transform3D.IDENTITY
 
 func _on_vr_setup_failed() -> void:

project/aircraft/aircraft.tscn

@@ -55,6 +55,11 @@ tracker = &"/user/vive_tracker_htcx/role/camera"
 transform = Transform3D(0.25, 0, 0, 0, 0.25, 0, 0, 0, 0.25, 0, 0, 0)
 visible = false
 
+[node name="RecentTracking" type="Timer" parent="AttitudeRoot/PilotEyes/PilotFloor/XROrigin3D"]
+wait_time = 5.0
+one_shot = true
+ignore_time_scale = true
+
 [node name="FallbackCamera" type="Camera3D" parent="AttitudeRoot/PilotEyes"]
 transform = Transform3D(1, 0, 0, 0, 0.980955, 0.194234, 0, -0.194234, 0.980955, 0, 0, 0)
 
@@ -65,5 +70,6 @@ transform = Transform3D(-0.5, -1.27582e-08, 7.43353e-08, 4.33325e-10, 0.4923, 0.
 hostname = "192.168.1.2"
 
 [connection signal="use_fallback" from="." to="AttitudeRoot/PilotEyes" method="_on_aircraft_use_fallback"]
+[connection signal="timeout" from="AttitudeRoot/PilotEyes/PilotFloor/XROrigin3D/RecentTracking" to="." method="_on_recent_tracking_timeout"]
 
 [editable path="Mi-2"]