implemented hookes law with the suspension

wheel.gd

@@ -0,0 +1,32 @@
+class_name Wheel
+extends RayCast3D
+
+@export var wheel_radius: float = 0.316
+@export var suspension_rest_length: float = 0.1
+@export var suspension_stiffness: float = 250_000
+
+func _ready() -> void:
+	target_position *= suspension_rest_length + wheel_radius
+
+func apply_forces(car: Car) -> void:
+	force_raycast_update()
+	
+	var force: Vector3 = get_suspension_force()
+	car.apply_force(force, car.to_local(get_collision_point()))
+
+func get_suspension_force() -> Vector3:
+	var up: Vector3 = global_basis.y
+	if not is_colliding():
+		$"RX-Wheel".position = -up * suspension_rest_length
+		return Vector3.ZERO
+	
+	var collision_point: Vector3 = to_local(get_collision_point())
+	var wheel_center: Vector3 = collision_point + (up * wheel_radius)
+	$"RX-Wheel".position = wheel_center
+	var suspension_length: float = -up.dot(wheel_center)
+	var suspension_displacement: float = suspension_rest_length - suspension_length
+	#https://en.wikipedia.org/wiki/Hookes_law
+	var y_force_scalar: float = suspension_stiffness * suspension_displacement
+	var force: Vector3 = Vector3.UP * y_force_scalar
+	
+	return force