# Trouble with local velocity

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Hello everyone,
I have the ball on my stage and it keeps going forward. There are some checkpoints and I successfully change direction at these points. The problem starts right here after the change of direction. I can’t make left and right turns from the user after a change of direction. I am confused about what change i need to make where i marked with code

``````func _physics_process(delta):
velocity= direction* delta * max_speed*10
if translation.distance_to(points[current_point].translation) < 3:
if current_point +1 == len(points):
return
else:
current_point += 1
rotate_y(-90)
camera.rotate_y(-90)
camera.offset=Vector3(-10,5,0)
direction = (points[current_point].translation - translation).normalized()
if Input.is_action_pressed("ui_left"):
velocity.x = lerp(velocity.x, -max_speed, 0.1)   ##### Here #####
if Input.is_action_pressed("ui_right"):
velocity.x = lerp(velocity.x, max_speed, 0.1)    ##### Here #####
if !is_on_floor():
velocity.y -=  max_speed/12
move_and_slide(velocity)
``````

Just an FYI, the `delta` parameter doesn’t have to be factored into the velocity when using the `move_and_slide()` function. Also, may I suggest doing the velocity calculation after adjusting the variable. For example:

``````#...
# Do all the velocity calculations above, then factor in the speed numbers below.
velocity= direction * max_speed * 10
move_and_slide(velocity)
``````

Ertain | 2022-12-04 19:05

When I don’t use delta, the ball stays still and doesn’t move at all.
I did what you said about velocity.

Game_gulf | 2022-12-04 19:42

Then I don’t know what exactly the problem is, since the engine’s documentation says that `delta` doesn’t have to be included in the velocity calculation for `move_and_slide()`. Maybe it has something to do with the use of translations?

Ertain | 2022-12-04 20:03

it should not equal x while doing the rotation.

here:

``````if Input.is_action_pressed("ui_left"):
velocity.x = lerp(velocity.x, -max_speed, 0.1)
``````

Game_gulf | 2022-12-04 21:09