ChocoDriver/godot/component/entity/vehicles/biplan/biplan.gd

class_name Biplan
extends SeatedVehicle

const PLANE_FORWARD := Vector3.BACK # z increases when moving forward

@export var thrust_power: float = 10000.0
@export var turn_to_torque: float = 2000.0
@export var move_to_pitch: float = 4000.0
@export var wing_resistance: float = 5000.0
@export var lift: float = 100.0

var target_torque: float = 0.0
var target_pitch: float = 0.0
var target_rotation := Vector3.ZERO
var target_thrust := Vector3.ZERO


func trigger_thrust(activate: bool) -> void:
	if activate:
		target_thrust = PLANE_FORWARD * thrust_power
	else:
		target_thrust = Vector3.ZERO


func trigger_direction(dir: Vector2) -> void:
	target_torque = dir.x * turn_to_torque
	target_pitch = dir.y * move_to_pitch


func get_free_seat() -> Node3D:
	return $DrivingSeat


func _physics_process(_delta) -> void:
	# Command part
	_apply_plane_rotation()
	_apply_plane_thrust()

	# Air simulation part
	if is_sleeping():
		return

	_apply_wing_resistance()
	_apply_lift()


func _apply_plane_rotation() -> void:
	var torque: Vector3 = transform.basis * Vector3(target_pitch, 0.0, target_torque)
	apply_torque(torque)


func _apply_plane_thrust() -> void:
	var force: Vector3 = transform.basis * target_thrust
	apply_central_force(force)


func _apply_wing_resistance() -> void:
	var vertical_speed = linear_velocity.dot(transform.basis * Vector3.UP)
	var local_wing_force = Vector3.UP * -wing_resistance * vertical_speed
	var wing_force = transform.basis * local_wing_force
	print("= = =")
	print("Vertical speed : ", vertical_speed)
	print("Wing force local :", local_wing_force)
	print("Wing force : ", wing_force)
	apply_central_force(wing_force)


func _apply_lift() -> void:
	var forward_speed = linear_velocity.dot(transform.basis * PLANE_FORWARD)
	if forward_speed < 0.0 :
		forward_speed = 0.0
	var local_lift_force = Vector3.UP * lift * forward_speed
	var lift_force = transform.basis * local_lift_force
	print("- - -")
	print("Forward speed : ", forward_speed)
	print("Lift force local :", local_lift_force)
	print("Lift force : ", lift_force)
	apply_central_force(lift_force)


func _on_dir_changed(dir: Vector2) -> void:
	trigger_direction(dir)


func _on_main_action(pressed: bool) -> void:
	trigger_thrust(pressed)