For our regular monthly tutorial nights, we're basing our teaching on the wonderful series by AJ's Learning Lab, Godot FPS Tutorial - Learn Godot by making Wolfenstein 3D.

He has made the assets he uses freely available (please consider donating) here: https://ajslearninglab.itch.io/boganstein-3d-learn-godot-4-with-wolfenstein-3d/

All the code we use is available on AJ's Learning Lab github - https://github.com/AJsLearningLab/GodotFPS

extends CanvasLayer
 
var time_since_last_shot = 0.0
var fire_rate = 1.0
var can_shoot = true
var weapon_textures = {
	"gun": preload("res://hudgun.png"),
	"machine": preload("res://hudmachinegun.png"),
	"mini": preload("res://hudmini.png"),
	"knife": preload("res://hudknife.png")  # and so on for each weapon
}
 
func _ready():
	$AnimatedSprite2D.animation_finished.connect(_on_AnimatedSprite2D_animation_finished)
	$AnimatedSprite2D.play(Global.current_weapon + "_idle")
	$bj.play("100")  # Assuming that '100' is the animation for full health
	update_weapon_icon()
 
func _process(delta):
	time_since_last_shot += delta
	can_shoot = time_since_last_shot >= (1.0 / fire_rate)
 
	if Global.current_weapon != "knife" and Global.ammo <= 0:
		Global.current_weapon = "knife"
		$AnimatedSprite2D.play("knife_idle")
 
	if Input.is_action_pressed("ui_select") and can_shoot:
 
		if Global.current_weapon == "knife":
			$AnimatedSprite2D.play("stab")
		else:
			$AnimatedSprite2D.play(Global.current_weapon + "_shoot")
 
		time_since_last_shot = 0.0
 
		if Global.current_weapon != "knife":
			if Global.ammo > 0:
				Global.ammo -= 1
 
	match Global.current_weapon:
		"gun":
			fire_rate = 3.0
		"machine":
			fire_rate = 6.0
		"mini":
			fire_rate = 10.0
		"knife":
			fire_rate = 2.0
		_:
			fire_rate = 1.0
 
	update_weapon_icon()
	update_health_label()
	update_ammo_label()
	update_lives_label()
	update_score_label()
	update_level_label()
	update_face_animation(Global.player_health)
 
func update_weapon_icon():
	if $WEAPON.texture != weapon_textures[Global.current_weapon]:
		$WEAPON.texture = weapon_textures[Global.current_weapon]
 
func _on_AnimatedSprite2D_animation_finished():
	$AnimatedSprite2D.play(Global.current_weapon + "_idle")
 
func update_health_label():
	$HEALTH.text = str(Global.player_health)
 
func update_lives_label():
	$LIVES.text = str(Global.lives)
 
func update_score_label():
	$SCORE.text = str(Global.player_score)
 
func update_level_label():
	$LEVEL.text = str(Global.current_level)
 
func update_ammo_label():
	$AMMO.text = str(Global.ammo)
 
 
func update_face_animation(health):
	var animation_name = ""
	if health > 90:
		animation_name = "100"
	elif health > 75:
		animation_name = "90"
	elif health > 60:
		animation_name = "75"
	elif health > 45:
		animation_name = "60"
	elif health > 30:
		animation_name = "45"
	elif health > 15:
		animation_name = "30"
	else:
		animation_name = "15"
 
	$bj.play(animation_name)