From 7842e15c6c5ceefb10c004937064b6917a8db598 Mon Sep 17 00:00:00 2001
From: Felipe M <me@fmartingr.com>
Date: Sat, 30 Jan 2021 22:58:28 +0100
Subject: [PATCH] Lessons: Player health, damage, stats, resources

---
 metroidvania/ResourceLoader.gd                |  4 ++
 metroidvania/Scenes/Enemies/Enemy.gd          |  6 +-
 metroidvania/Scenes/Enemies/Enemy.tscn        | 10 +++-
 metroidvania/Scenes/Enemies/EnemyStats.gd     | 13 ++++
 metroidvania/Scenes/Enemies/EnemyStats.tscn   |  6 ++
 metroidvania/Scenes/Enemies/WalkingEnemy.tscn | 15 ++++-
 metroidvania/Scenes/Player/Player.gd          | 18 ++++++
 metroidvania/Scenes/Player/Player.tscn        | 59 ++++++++++++++++---
 .../Scenes/Player/PlayerCollider.tres         |  4 ++
 metroidvania/Scenes/Player/PlayerStats.gd     | 13 ++++
 metroidvania/Scenes/Player/PlayetStats.tres   |  6 ++
 metroidvania/Scenes/World/World.tscn          |  7 +--
 metroidvania/project.godot                    | 10 +++-
 13 files changed, 153 insertions(+), 18 deletions(-)
 create mode 100644 metroidvania/ResourceLoader.gd
 create mode 100644 metroidvania/Scenes/Enemies/EnemyStats.gd
 create mode 100644 metroidvania/Scenes/Enemies/EnemyStats.tscn
 create mode 100644 metroidvania/Scenes/Player/PlayerCollider.tres
 create mode 100644 metroidvania/Scenes/Player/PlayerStats.gd
 create mode 100644 metroidvania/Scenes/Player/PlayetStats.tres

diff --git a/metroidvania/ResourceLoader.gd b/metroidvania/ResourceLoader.gd
new file mode 100644
index 0000000..fa14999
--- /dev/null
+++ b/metroidvania/ResourceLoader.gd
@@ -0,0 +1,4 @@
+extends Node
+
+# warning-ignore-all:unused_class_variables
+var PlayerStats = preload("res://Scenes/Player/PlayetStats.tres")
diff --git a/metroidvania/Scenes/Enemies/Enemy.gd b/metroidvania/Scenes/Enemies/Enemy.gd
index 17218aa..5866d03 100644
--- a/metroidvania/Scenes/Enemies/Enemy.gd
+++ b/metroidvania/Scenes/Enemies/Enemy.gd
@@ -2,8 +2,12 @@ extends KinematicBody2D
 
 export (int) var MAX_SPEED = 15
 
+onready var stats = $EnemyStats
+
 var motion = Vector2.ZERO
 
+func _on_Hurtbox_hit(damage):
+	stats.health -= damage
 
-func _on_Hurtbox_hit(_damage):
+func _on_EnemyStats_enemy_died():
 	queue_free()
diff --git a/metroidvania/Scenes/Enemies/Enemy.tscn b/metroidvania/Scenes/Enemies/Enemy.tscn
index 1a2d466..7b7219a 100644
--- a/metroidvania/Scenes/Enemies/Enemy.tscn
+++ b/metroidvania/Scenes/Enemies/Enemy.tscn
@@ -1,7 +1,9 @@
-[gd_scene load_steps=3 format=2]
+[gd_scene load_steps=5 format=2]
 
 [ext_resource path="res://Scenes/Enemies/Enemy.gd" type="Script" id=1]
 [ext_resource path="res://Scenes/Objects/Hurtbox.tscn" type="PackedScene" id=2]
+[ext_resource path="res://Scenes/Enemies/EnemyStats.tscn" type="PackedScene" id=3]
+[ext_resource path="res://Scenes/Objects/Hitbox.tscn" type="PackedScene" id=4]
 
 [node name="Enemy" type="KinematicBody2D"]
 collision_layer = 0
@@ -16,4 +18,10 @@ script = ExtResource( 1 )
 
 [node name="Hurtbox" parent="." instance=ExtResource( 2 )]
 collision_mask = 8
+
+[node name="Hitbox" parent="." instance=ExtResource( 4 )]
+collision_mask = 4
+
+[node name="EnemyStats" parent="." instance=ExtResource( 3 )]
 [connection signal="hit" from="Hurtbox" to="." method="_on_Hurtbox_hit"]
+[connection signal="enemy_died" from="EnemyStats" to="." method="_on_EnemyStats_enemy_died"]
diff --git a/metroidvania/Scenes/Enemies/EnemyStats.gd b/metroidvania/Scenes/Enemies/EnemyStats.gd
new file mode 100644
index 0000000..2ff19f3
--- /dev/null
+++ b/metroidvania/Scenes/Enemies/EnemyStats.gd
@@ -0,0 +1,13 @@
+extends Node
+
+signal enemy_died
+
+export (int) var max_health = 1
+
+# Needs to be onready to use the max_health variable
+onready var health = max_health setget set_health
+
+func set_health(value):
+	health = clamp(value, 0, max_health)
+	if health == 0:
+		emit_signal("enemy_died")
diff --git a/metroidvania/Scenes/Enemies/EnemyStats.tscn b/metroidvania/Scenes/Enemies/EnemyStats.tscn
new file mode 100644
index 0000000..c60f0e6
--- /dev/null
+++ b/metroidvania/Scenes/Enemies/EnemyStats.tscn
@@ -0,0 +1,6 @@
+[gd_scene load_steps=2 format=2]
+
+[ext_resource path="res://Scenes/Enemies/EnemyStats.gd" type="Script" id=1]
+
+[node name="EnemyStats" type="Node"]
+script = ExtResource( 1 )
diff --git a/metroidvania/Scenes/Enemies/WalkingEnemy.tscn b/metroidvania/Scenes/Enemies/WalkingEnemy.tscn
index 4bde810..baf52b3 100644
--- a/metroidvania/Scenes/Enemies/WalkingEnemy.tscn
+++ b/metroidvania/Scenes/Enemies/WalkingEnemy.tscn
@@ -1,4 +1,4 @@
-[gd_scene load_steps=7 format=2]
+[gd_scene load_steps=8 format=2]
 
 [ext_resource path="res://Scenes/Enemies/WalkingEnemy.gd" type="Script" id=1]
 [ext_resource path="res://Assets/Enemies/WalkingEnemy.png" type="Texture" id=2]
@@ -26,9 +26,11 @@ tracks/0/keys = {
 [sub_resource type="RectangleShape2D" id=3]
 extents = Vector2( 7, 6 )
 
+[sub_resource type="RectangleShape2D" id=4]
+extents = Vector2( 8, 6 )
+
 [node name="WalkingEnemy" instance=ExtResource( 3 )]
 script = ExtResource( 1 )
-MAX_SPEED = 15
 
 [node name="Sprite" parent="." index="0"]
 position = Vector2( 0, -9 )
@@ -76,4 +78,13 @@ collision_mask = 0
 position = Vector2( 0, -7 )
 shape = SubResource( 3 )
 
+[node name="Collider" parent="Hitbox" index="0"]
+position = Vector2( 0, -8 )
+shape = SubResource( 4 )
+
+[node name="EnemyStats" parent="." index="9"]
+max_health = 3
+
 [editable path="Hurtbox"]
+
+[editable path="Hitbox"]
diff --git a/metroidvania/Scenes/Player/Player.gd b/metroidvania/Scenes/Player/Player.gd
index 0c19342..56dbdb6 100644
--- a/metroidvania/Scenes/Player/Player.gd
+++ b/metroidvania/Scenes/Player/Player.gd
@@ -4,6 +4,8 @@ const DustEffect = preload("res://Scenes/Effects/DustEffect.tscn")
 const PlayerBullet = preload("res://Scenes/Player/PlayerBullet.tscn")
 const JumpEffect = preload("res://Scenes/Effects/JumpEffect.tscn")
 
+var PlayerStats = ResourceLoader.PlayerStats
+
 export (int) var acceleration = 512
 export (int) var max_speed = 64
 export (float) var friction = 0.25
@@ -12,6 +14,7 @@ export (int) var jump_force = 128
 export (int) var max_slope = 46
 export (int) var bullet_speed = 250
 
+var invincible = false setget set_invincible
 var motion = Vector2.ZERO
 var snap_vector = Vector2.ZERO
 var just_jumped= false
@@ -22,8 +25,15 @@ onready var coyoteJumpTimer = $CoyoteJumpTimer
 onready var playerGun = $Sprite/PlayerGun
 onready var muzzle = $Sprite/PlayerGun/Sprite/Muzzle
 onready var fireBulletTimer = $FireBulletTimer
+onready var blinkAnimator = $BlinkAnimator
 
 
+func set_invincible(value):
+	invincible = value
+
+func _ready():
+	PlayerStats.connect("player_died", self, "_on_died")
+
 func _physics_process(delta):
 	just_jumped = false
 	var input_vector = get_input_vector()
@@ -125,3 +135,11 @@ func move():
 	if is_on_floor() and get_floor_velocity().length() == 0 and abs(motion.x) < 1:
 		position.x = last_position.x
 
+func _on_Hurtbox_hit(damage):
+	if not invincible:
+		PlayerStats.health -= damage
+		blinkAnimator.play("Blink")
+
+
+func _on_died():
+	queue_free()
diff --git a/metroidvania/Scenes/Player/Player.tscn b/metroidvania/Scenes/Player/Player.tscn
index 2ffd76d..9cfacd8 100644
--- a/metroidvania/Scenes/Player/Player.tscn
+++ b/metroidvania/Scenes/Player/Player.tscn
@@ -1,14 +1,11 @@
-[gd_scene load_steps=9 format=2]
+[gd_scene load_steps=11 format=2]
 
 [ext_resource path="res://Assets/Player/Player.png" type="Texture" id=1]
 [ext_resource path="res://Scenes/Player/Player.gd" type="Script" id=2]
 [ext_resource path="res://DebugKinematicBody2D.tscn" type="PackedScene" id=3]
 [ext_resource path="res://Scenes/Player/PlayerGun.tscn" type="PackedScene" id=4]
-
-
-
-[sub_resource type="RectangleShape2D" id=1]
-extents = Vector2( 4, 7 )
+[ext_resource path="res://Scenes/Objects/Hurtbox.tscn" type="PackedScene" id=5]
+[ext_resource path="res://Scenes/Player/PlayerCollider.tres" type="Shape2D" id=6]
 
 [sub_resource type="Animation" id=2]
 resource_name = "Idle"
@@ -77,6 +74,39 @@ tracks/1/keys = {
 } ]
 }
 
+[sub_resource type="Animation" id=5]
+resource_name = "Blink"
+length = 0.9
+tracks/0/type = "value"
+tracks/0/path = NodePath("Sprite:visible")
+tracks/0/interp = 1
+tracks/0/loop_wrap = true
+tracks/0/imported = false
+tracks/0/enabled = true
+tracks/0/keys = {
+"times": PoolRealArray( 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9 ),
+"transitions": PoolRealArray( 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 ),
+"update": 1,
+"values": [ false, true, false, true, false, true, false, true, false, true ]
+}
+tracks/1/type = "method"
+tracks/1/path = NodePath(".")
+tracks/1/interp = 1
+tracks/1/loop_wrap = true
+tracks/1/imported = false
+tracks/1/enabled = true
+tracks/1/keys = {
+"times": PoolRealArray( 0, 0.9 ),
+"transitions": PoolRealArray( 1, 1 ),
+"values": [ {
+"args": [ true ],
+"method": "set_invincible"
+}, {
+"args": [ false ],
+"method": "set_invincible"
+} ]
+}
+
 [node name="Player" type="KinematicBody2D"]
 collision_mask = 2
 script = ExtResource( 2 )
@@ -93,13 +123,16 @@ position = Vector2( 1, 3 )
 
 [node name="Collision" type="CollisionShape2D" parent="."]
 position = Vector2( 0, -7 )
-shape = SubResource( 1 )
+shape = ExtResource( 6 )
 
 [node name="Animation" type="AnimationPlayer" parent="."]
 anims/Idle = SubResource( 2 )
 anims/Jump = SubResource( 3 )
 anims/Run = SubResource( 4 )
 
+[node name="BlinkAnimator" type="AnimationPlayer" parent="."]
+anims/Blink = SubResource( 5 )
+
 [node name="Debug" parent="." instance=ExtResource( 3 )]
 visible = false
 
@@ -115,3 +148,15 @@ one_shot = true
 [node name="FireBulletTimer" type="Timer" parent="."]
 wait_time = 0.3
 one_shot = true
+
+[node name="Hurtbox" parent="." instance=ExtResource( 5 )]
+collision_layer = 4
+
+[node name="Collider" parent="Hurtbox" index="0"]
+position = Vector2( 0, -7 )
+shape = ExtResource( 6 )
+
+[node name="InvincibleTimer" type="Timer" parent="."]
+[connection signal="hit" from="Hurtbox" to="." method="_on_Hurtbox_hit"]
+
+[editable path="Hurtbox"]
diff --git a/metroidvania/Scenes/Player/PlayerCollider.tres b/metroidvania/Scenes/Player/PlayerCollider.tres
new file mode 100644
index 0000000..d7e085a
--- /dev/null
+++ b/metroidvania/Scenes/Player/PlayerCollider.tres
@@ -0,0 +1,4 @@
+[gd_resource type="RectangleShape2D" format=2]
+
+[resource]
+extents = Vector2( 4, 7 )
diff --git a/metroidvania/Scenes/Player/PlayerStats.gd b/metroidvania/Scenes/Player/PlayerStats.gd
new file mode 100644
index 0000000..abd6917
--- /dev/null
+++ b/metroidvania/Scenes/Player/PlayerStats.gd
@@ -0,0 +1,13 @@
+extends Resource
+class_name PlayerStats
+
+var max_health = 4
+var health = max_health setget set_health
+
+signal player_died
+
+func set_health(value):
+	health = clamp(value, 0, max_health)
+	
+	if health == 0:
+		emit_signal("player_died")
diff --git a/metroidvania/Scenes/Player/PlayetStats.tres b/metroidvania/Scenes/Player/PlayetStats.tres
new file mode 100644
index 0000000..88e1f78
--- /dev/null
+++ b/metroidvania/Scenes/Player/PlayetStats.tres
@@ -0,0 +1,6 @@
+[gd_resource type="Resource" load_steps=2 format=2]
+
+[ext_resource path="res://Scenes/Player/PlayerStats.gd" type="Script" id=1]
+
+[resource]
+script = ExtResource( 1 )
diff --git a/metroidvania/Scenes/World/World.tscn b/metroidvania/Scenes/World/World.tscn
index d3db9c4..14a01ac 100644
--- a/metroidvania/Scenes/World/World.tscn
+++ b/metroidvania/Scenes/World/World.tscn
@@ -30,12 +30,9 @@ position = Vector2( 64, 128 )
 position = Vector2( 32, 160 )
 
 [node name="WalkingEnemy2" parent="." instance=ExtResource( 5 )]
-position = Vector2( 144, 208 )
+position = Vector2( 160, 208 )
 
 [node name="WalkingEnemy3" parent="." instance=ExtResource( 5 )]
-position = Vector2( 208, 96 )
-
-[node name="WalkingEnemy4" parent="." instance=ExtResource( 5 )]
-position = Vector2( 320, 128 )
+position = Vector2( 448, 80 )
 
 [editable path="Player"]
diff --git a/metroidvania/project.godot b/metroidvania/project.godot
index 42d369b..dc7374e 100644
--- a/metroidvania/project.godot
+++ b/metroidvania/project.godot
@@ -8,9 +8,14 @@
 
 config_version=4
 
-_global_script_classes=[  ]
+_global_script_classes=[ {
+"base": "Resource",
+"class": "PlayerStats",
+"language": "GDScript",
+"path": "res://Scenes/Player/PlayerStats.gd"
+} ]
 _global_script_class_icons={
-
+"PlayerStats": ""
 }
 
 [application]
@@ -22,6 +27,7 @@ config/icon="res://icon.png"
 [autoload]
 
 Utils="*res://Utils.gd"
+ResourceLoader="*res://ResourceLoader.gd"
 
 [display]