| extends CharacterBody2D |
|
|
| const pad = 100 |
| const WIDTH = 1280 |
| const HEIGHT = 720 |
| const MAX_FRUIT = 10 |
| var _bounds := Rect2(pad, pad, WIDTH - 2 * pad, HEIGHT - 2 * pad) |
|
|
| @export var speed := 500 |
| @export var friction = 0.18 |
| var _velocity := Vector2.ZERO |
| var _action = Vector2.ZERO |
| @onready var fruit = $"../Fruit" |
| @onready var raycast_sensor = $"RaycastSensor2D" |
| @onready var walls := $"../Walls" |
| @onready var colision_shape := $"CollisionShape2D" |
| @onready var ai_controller := $AIController2D |
| var fruit_just_entered = false |
| var just_hit_wall = false |
| var best_fruit_distance = 10000.0 |
| var fruit_count = 0 |
|
|
|
|
| func _ready(): |
| ai_controller.init(self) |
| raycast_sensor.activate() |
|
|
|
|
| func _physics_process(_delta): |
| var direction = get_direction() |
| if direction.length() > 1.0: |
| direction = direction.normalized() |
| # Using the follow steering behavior. |
| var target_velocity = direction * speed |
| _velocity += (target_velocity - _velocity) * friction |
| set_velocity(_velocity) |
| move_and_slide() |
| _velocity = velocity |
|
|
| update_reward() |
|
|
| if Input.is_action_just_pressed("r_key"): |
| game_over() |
|
|
|
|
| func game_over(): |
| fruit_just_entered = false |
| just_hit_wall = false |
| fruit_count = 0 |
| _velocity = Vector2.ZERO |
| _action = Vector2.ZERO |
| position = _calculate_new_position() |
| spawn_fruit() |
| best_fruit_distance = position.distance_to(fruit.position) |
| ai_controller.reset() |
|
|
|
|
| func _calculate_new_position(current_position: Vector2 = Vector2.ZERO) -> Vector2: |
| var new_position := Vector2.ZERO |
| new_position.x = randf_range(_bounds.position.x, _bounds.end.x) |
| new_position.y = randf_range(_bounds.position.y, _bounds.end.y) |
|
|
| if (current_position - new_position).length() < 4.0 * colision_shape.shape.get_radius(): |
| return _calculate_new_position(current_position) |
|
|
| var radius = colision_shape.shape.get_radius() |
| var rect = Rect2(new_position - Vector2(radius, radius), Vector2(radius * 2, radius * 2)) |
| for wall in walls.get_children(): |
| #wall = wall as Area2D |
| var cr = wall.get_node("ColorRect") |
| var rect2 = Rect2(cr.get_position() + wall.position, cr.get_size()) |
| if rect.intersects(rect2): |
| return _calculate_new_position() |
|
|
| return new_position |
|
|
|
|
| func get_direction(): |
| if ai_controller.done: |
| _velocity = Vector2.ZERO |
| return Vector2.ZERO |
|
|
| if ai_controller.heuristic == "model": |
| return _action |
|
|
| var direction := Vector2( |
| Input.get_action_strength("move_right") - Input.get_action_strength("move_left"), |
| Input.get_action_strength("move_down") - Input.get_action_strength("move_up") |
| ) |
|
|
| return direction |
|
|
|
|
| func get_fruit_position(): |
| return $"../Fruit".global_position |
|
|
|
|
| func update_reward(): |
| ai_controller.reward -= 0.01 # step penalty |
| ai_controller.reward += shaping_reward() |
|
|
|
|
| func shaping_reward(): |
| var s_reward = 0.0 |
| var fruit_distance = position.distance_to(fruit.position) |
|
|
| if fruit_distance < best_fruit_distance: |
| s_reward += best_fruit_distance - fruit_distance |
| best_fruit_distance = fruit_distance |
|
|
| s_reward /= 100.0 |
| return s_reward |
|
|
|
|
| func spawn_fruit(): |
| fruit.position = _calculate_new_position(position) |
| best_fruit_distance = position.distance_to(fruit.position) |
|
|
|
|
| func fruit_collected(): |
| fruit_just_entered = true |
| ai_controller.reward += 10.0 |
| fruit_count += 1 |
| spawn_fruit() |
|
|
|
|
| func wall_hit(): |
| ai_controller.done = true |
| ai_controller.reward -= 10.0 |
| just_hit_wall = true |
| game_over() |
|
|
|
|
| func _on_Fruit_body_entered(_body): |
| fruit_collected() |
|
|
|
|
| func _on_LeftWall_body_entered(_body): |
| wall_hit() |
|
|
|
|
| func _on_RightWall_body_entered(_body): |
| wall_hit() |
|
|
|
|
| func _on_TopWall_body_entered(_body): |
| wall_hit() |
|
|
|
|
| func _on_BottomWall_body_entered(_body): |
| wall_hit() |
|
|
