Enemy.gd

1	extends KinematicBody2D
2	class_name Enemy
3
4	onready var damage_points = $DamagePoints
5	onready var navigation_agent: NavigationAgent2D = $NavigationAgent2D
6	onready var viewcone_polygon2d: Polygon2D = $ViewconePolygon2D
7	const Utils = preload("res://utils/Utils.gd")
8	const Explosion = preload("res://effects/Explosion.tscn")
9	const Smoke = preload("res://effects/Smoke.tscn")
10	const Damage = preload("res://effects/Damage.tscn")
11	const Constants = preload("res://utils/Constants.gd")
12	const Weapons = preload("res://weapons/Weapons.gd")
13
14	export var is_invincible = false
15	export var move_speed = Constants.SPEED * 1.05
16	export var turn_rate = 0.03
17	export var health = -1
18	export var max_health = 100
19	export var is_targeted = false
20	export var target: Vector2
21	export var follow_target = false
22	signal enemy_killed(position)
23
24	var player: Node2D
25	var weapon: Weapon
26	var velocity = Vector2.ZERO
27	var dead = false
28	var health_ratio
29	var health_percentage
30	var sees_player: bool
31
32	func _ready() -> void:
33	weapon = Weapons.create_basic_enemy_gun()
34	navigation_agent.max_speed = move_speed
35	var _err = navigation_agent.connect("path_changed", self, "path_changed")
36	_err = navigation_agent.connect("velocity_computed", self, "velocity_computed")
37	_err = navigation_agent.connect("target_reached", self, "target_reached")
38	var players = get_tree().get_nodes_in_group("player")
39	self.player = players[0]
40
41	$AnimationPlayer.play("fade_in")
42	if health < 0 or health > max_health:
43	health = max_health
44	else:
45	var hurt_points = max_health - health
46	health = max_health
47	for i in hurt_points:
48	hurt()
49
50	func path_changed() -> void:
51	pass
52
53	func velocity_computed(new_vel: Vector2) -> void:
54	velocity = move_and_slide(new_vel)
55	global_rotation = velocity.angle() + PI/2.0
56	pass
57
58	func target_reached() -> void:
59	Utils.log("enemy", self, "reached player", player, "at", self.position)
60	player.hurt(25)
61	var explosion = Explosion.instance()
62	explosion.transform = transform
63	get_parent().add_child(explosion)
64	kill()
65	pass
66
67	func _process(_delta: float) -> void:
68	var is_player_in_visibility_cone = Geometry.is_point_in_polygon(player.global_position, viewcone_polygon2d.polygon)
69	if is_player_in_visibility_cone:
70	var space_state = get_world_2d().direct_space_state
71	var intersections = space_state.intersect_ray(global_position, player.global_position, [self])
72	if intersections.size() == 1:
73	var collider = intersections[0]['collider']
74	sees_player = collider == player
75
76	if sees_player:
77	set_target(player.global_position)
78
79	var pb: ProgressBar = $Graphics/Alive/Container/ProgressBar
80	health_ratio = float(health) / float(max_health)
81	health_percentage = health_ratio * 100
82	pb.value = health_percentage
83	if health_percentage < 20:
84	pb.modulate = Color.red
85	elif health_percentage < 60:
86	pb.modulate = Color.yellow
87	else:
88	pb.modulate = Color.blue
89	$Graphics/Alive/Container.global_rotation = 0
90	$Graphics/Alive/Sprite/Target.visible = is_targeted
91	$Graphics/Alive/Sprite/Target.global_rotation = 0
92	$Graphics/Alive/Sprite/Trails.add_position(global_position)
93
94	var dist_to_player = global_position.distance_to(player.global_position)
95	# Utils.log("dist to player", dist_to_player)
96	if dist_to_player < 25:
97	target_reached()
98
99	var should_shoot = dist_to_player < weapon.shooting_range
100	if should_shoot:
101	var space_state = get_world_2d().direct_space_state
102	var intersections = space_state.intersect_ray(global_position, player.global_position, [self])
103	var hits_player = intersections and intersections.collider == player
104	if hits_player:
105	weapon.try_shoot(self, player.global_position)
106
107	func _physics_process(delta: float) -> void:
108	if dead:
109	return
110
111	# navigate to the next position
112	var current_pos = global_position
113	var next_pos = navigation_agent.get_next_location()
114	var diff: Vector2 = next_pos - current_pos
115	var dir = diff.normalized()
116	var desired_vel = dir * navigation_agent.max_speed
117	var steering = (desired_vel - velocity) * delta * 4
118	var new_vel = velocity + steering
119	velocity = new_vel
120
121	if navigation_agent.avoidance_enabled:
122	navigation_agent.set_velocity(velocity)
123	else:
124	velocity_computed(velocity)
125
126	func set_target(pos: Vector2):
127	# var to_dir = (pos - global_position).normalized()
128	# var curr_dir = velocity.normalized()
129	# var dir_diff = to_dir - curr_dir
130	# var change = dir_diff * turn_rate * move_speed
131	# velocity = (velocity + change).normalized() * move_speed
132	# var nav_map = navigation_agent.get_navigation_map()
133	# Utils.log("setting target location", pos, "map", nav_map)
134	navigation_agent.set_target_location(pos)
135
136	func _ensure_smoke_exists() -> void:
137	var max_smoke_count = $DamagePoints.get_child_count()
138	var existing_smoke_count = $DamageObjects.get_child_count()
139	var expected_smoke_count = ceil(health_ratio * max_smoke_count)
140	var smoke_to_add_count = expected_smoke_count - existing_smoke_count
141	for i in smoke_to_add_count:
142	var smoke = Smoke.instance()
143	var smoke_pos = get_damage_point_on_body()
144	smoke.position = smoke_pos
145	$DamageObjects.add_child(smoke)
146
147	func hurt(damage: int = 1):
148	if dead \|\| is_invincible:
149	return
150	health -= damage
151	add_damage_label(damage)
152	# add_child(smoke)
153	_ensure_smoke_exists()
154	if health <= 0:
155	kill()
156
157	func kill():
158	if dead \|\| is_invincible:
159	return
160	dead = true
161	$Graphics/Alive.hide()
162	$CollisionPolygon2D.set_deferred("disabled", true)
163	var explosion = Explosion.instance()
164	explosion.connect("explosion_done", self, "_on_death_explosion_finished")
165	$Graphics.add_child(explosion)
166	z_index = -1
167	emit_signal("enemy_killed", global_position)
168
169	func add_damage_label(damage_amount: int = 5) -> void:
170	var damage_label: Damage = Damage.instance()
171	damage_label.value = -damage_amount
172	damage_label.position = self.position
173	get_tree().root.add_child(damage_label)
174
175	func teleport(dest: Vector2) -> void:
176	$Graphics/Alive/Sprite/Trails.clear()
177	position = dest
178
179	func _on_death_explosion_finished():
180	$AnimationPlayer.play("fade_out")
181
182	func get_damage_point_on_body() -> Vector2:
183	var child_count = damage_points.get_child_count()
184	var random_index = randi() % child_count
185	var random_child: Position2D = damage_points.get_child(random_index)
186	return random_child.position
187
188	func remove_thyself():
189	queue_free()
190
191	func _on_Area2D_body_entered(body: Node) -> void:
192	var is_player = body == player
193	if is_player:
194	player.hurt(2)
195	var explosion = Explosion.instance()
196	explosion.transform = transform
197	get_parent().add_child(explosion)
198	kill()