Enemy not rebounding off of walls multiple times.

Muhammad Aregbesola

My problem is pretty simple. When I start the game, the enemy starts moving left, facing left like it's supposed to. It hits the wall and then turned around, facing right and moving right. It hits the wall, and then it stops. Here is my code:

extends KinematicBody2D


export (int) var run_speed = 50
export (int) var jump_speed = -400
export (int) var gravity = 1200

var velocity = Vector2()
var jumping = false
var direction = 0


func get_input():
	if direction == 1:
		$Sprite.flip_h = 1
		velocity.x += run_speed
	if direction == -1:
		$Sprite.flip_h = 0
		velocity.x -= run_speed
	if is_on_wall() and direction == 1:
		velocity.x = 0
		direction = -1
		velocity.x -= run_speed
	if is_on_wall() and direction == -1:
		velocity.x = 0
		direction = 1
		velocity.x += run_speed
	
	

func _physics_process(delta):
	get_input()
	velocity = move_and_slide(velocity, Vector2(0, -1))

Please help me I have tried for two hours and don't know what to do

altria

What happen if you do it like this

extends KinematicBody2D

export (int) var run_speed = 50
export (int) var jump_speed = -400
export (int) var gravity = 1200

var velocity = Vector2()
var jumping = false
var direction = 0

func get_input():
	if direction == 1:
		$Sprite.flip_h = 1
		velocity.x += run_speed
		return
	if direction == -1:
		$Sprite.flip_h = 0
		velocity.x -= run_speed
		return

func _physics_process(delta):
	if is_on_wall():
		direction *= -1
	get_input()
	velocity = move_and_slide(velocity, Vector2(0, -1))

altria

Not on my pc right now but I'm suspicious about these lines:

  if is_on_wall() and direction == 1:
      velocity.x = 0
      direction = -1 # <- This
      velocity.x -= run_speed
  if is_on_wall() and direction == -1:  # <- And this
      velocity.x = 0
      direction = 1  
      velocity.x += run_speed

Assume it is now direction == 1, and is on wall is true. It will go to the first IF, the direction is now == -1, and then goes to the second IF, within same frame?

Try to continuously check for wall collisions on every physics step and reverse the direction whenever a collision is detected.

  func _physics_process(delta):
      get_input()

      if is_on_wall():
          direction *= -1  

      velocity = move_and_slide(velocity, Vector2(0, -1))

Muhammad Aregbesola

This is my code now:

extends KinematicBody2D


# Declare member variables here. Examples:
# var a = 2
# var b = "text"


# Called when the node enters the scene tree for the first time.
func _ready():
	pass # Replace with function body.


# Called every frame. 'delta' is the elapsed time since the previous frame.
#func _process(delta):
#	pass

export (int) var run_speed = 50
export (int) var jump_speed = -400
export (int) var gravity = 1200

var velocity = Vector2()
var jumping = false
var direction = -1


func get_input():
	if direction == 1:
		$Sprite.flip_h = 1
		velocity.x += run_speed
	if direction == -1:
		$Sprite.flip_h = 0
		velocity.x -= run_speed
	
	

func _physics_process(delta):
	  get_input()

	  if is_on_wall():
		  direction *= -1  

	  velocity = move_and_slide(velocity, Vector2(0, -1))

And it keeps turning around but doesn't go anywhere

altria

What happen if you do it like this

extends KinematicBody2D

export (int) var run_speed = 50
export (int) var jump_speed = -400
export (int) var gravity = 1200

var velocity = Vector2()
var jumping = false
var direction = 0

func get_input():
	if direction == 1:
		$Sprite.flip_h = 1
		velocity.x += run_speed
		return
	if direction == -1:
		$Sprite.flip_h = 0
		velocity.x -= run_speed
		return

func _physics_process(delta):
	if is_on_wall():
		direction *= -1
	get_input()
	velocity = move_and_slide(velocity, Vector2(0, -1))

Salodo

I think the problem might be because of the += and -= lets say the velocity is run speed then when it hits a wall you -= run speed meaning the velocity becomes zero and the enemy stands still, try just setting it directly using

velocity.x = run_speed
velocity.x = -run speed

Muhammad Aregbesola

It worked, thank you Altria!

altria

@Muhammad-Aregbesola Glad it help

Godot Community

Enemy not rebounding off of walls multiple times.