Move an enemy up and down from point a to point b repeatedly

AtlasBarked

Hey everyone. I'm very new to game dev and coding in general. I just followed a tutorial on making a Platformer and have one enemy type. I want to create another flying type that moves up and down between two defined points. Does anyone know the best way to do this? Thanks! For my first enemy type I have it move left and right using an if-then function and is_on_wall.

const FLOOR_NORMAL: = Vector2.UP
export var speed: = Vector2(30.0,100.0)
export var gravity: = 40.0
var velocity = Vector2.ZERO

func _ready():
set\_physics\_process(false)

velocity.x = -speed.x

func _physics_process(delta):
velocity.y += gravity \* delta

if is\_on\_wall():

	 velocity.x \*= -1.0

velocity.y = move\_and\_slide(velocity, FLOOR\_NORMAL).y

fire7side

Your y is your up and down. You can find the top y and the bottom y by getting the position in the editor and change speed to - when it reaches each one. You don't need gravity so that makes it easier. It's a good programming challenge. You'll be manipulating velocity.y instead of velocity.x.

AtlasBarked

Thanks for the help! I'll keep messing with it with your comment in mind. I keep getting a scenario where either my enemy doesn't appear when I run my level, the enemy goes up once and then gets stuck on the ground, or it doesn't move at all lol.

AtlasBarked

@fire7side said: Your y is your up and down. You can find the top y and the bottom y by getting the position in the editor and change speed to - when it reaches each one. You don't need gravity so that makes it easier. It's a good programming challenge. You'll be manipulating velocity.y instead of velocity.x.

Got it to work! Well, I kept gravity so it is more of a jumping than a flying one but it's gravity is pretty moon-like so for all intents and purposes it is flying.

I really just changed .x to .y in a couple spots and changed is_on_wall to is_on_floor.

Thanks again :)

extends KinematicBody2D


const FLOOR_NORMAL: = Vector2.UP

export var speed: = Vector2(30.0, 100.0)
export var gravity: = 40.0

export var points: = 5

var velocity = Vector2.ZERO

func _ready():
	set_physics_process(false)
	velocity.y = -speed.y
	
func _on_StompDetector_body_entered(body):
	if body.global_position.y > $StompDetector.global_position.y:
		return
	else:
		$CollisionShape2D.disabled = true
		die()

func _physics_process(delta):
	velocity.y += gravity * delta
	if is_on_floor():
		 velocity.y *= -speed.y
	velocity.y = move_and_slide(velocity, FLOOR_NORMAL).y

fire7side

Well, you got it. There are all kinds of ways to do it. Some people use a timer to decide when it should change motion. Every time you do something like that you learn a little more.