switch

scripts/train_movement.gd

@@ -1,21 +1,29 @@
 extends MeshInstance3D
+class_name TrainBody
 
 signal speed_changed(new_speed: float)
+signal rail_switched(old_rail: Path3D, new_rail: Path3D)
 
 @export_group("Train")
 @export var base_speed: float = 15.0
 @export var max_speed: float = 50.0
 @export var min_speed: float = 3.0
 @export var acceleration: float = 12.0
+@export var rail_a: Path3D
+@export var rail_b: Path3D
 
+var current_follower: PathFollow3D
+var current_rail: Path3D
 var current_speed: float = 15.0
 
 func _ready() -> void:
 	current_speed = base_speed
+	switch_to_rail(rail_a)
 
 
 func _process(delta: float) -> void:
 	_handle_input(delta)
+	current_follower.progress += current_speed * delta
 
 
 func _handle_input(delta: float) -> void:
@@ -29,3 +37,35 @@ func _handle_input(delta: float) -> void:
 
 func get_speed() -> float:
 	return current_speed
+
+
+func switch_to_rail(new_rail: Path3D) -> void:
+	if new_rail == current_rail:
+		return
+
+	current_rail = new_rail
+	current_follower = new_rail.get_node("TrainEngine") as PathFollow3D
+
+	var closest_offset = find_closest_point_on_path(new_rail, global_position)
+	current_follower.progress = closest_offset
+
+
+func find_closest_point_on_path(path: Path3D, point: Vector3) -> float:
+	var curve = path.curve
+	var closest_offset = 0.0
+	var min_distance = INF
+
+	var length = curve.get_baked_length()
+	var steps = 100  # Più alto = più preciso ma più lento
+
+	for i in range(steps + 1):
+		var offset = (float(i) / steps) * length
+		# Trasforma il punto locale della curva in coordinate globali
+		var path_point = path.global_transform * curve.sample_baked(offset)
+		var dist = point.distance_to(path_point)
+
+		if dist < min_distance:
+			min_distance = dist
+			closest_offset = offset
+
+	return closest_offset