WEAPON SWAYING?(Does anyone know how to use "linear_interpolation" in 3D?)

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:bust_in_silhouette: Asked By Star Frog

Does anyone know how to use “linear_interpolation” in 3D? I would make a weapon swaying, like PlanetSide2 or Battlefield. I think I had tried everything, but without some success. Here I’ve found the description of “linear_interpolate”: Interpolation — Godot Engine (3.1) documentation in English

Can somebody help me, please?

:bust_in_silhouette: Reply From: Magso

For something to sway you need to lerp using an amount that ping-pongs similar to Unity’s Mathf.PingPong.

Here’s a script that has a custom ping pong method.

export var number : float
export var pingpong_amount : float

func _process(delta):
	translation.lerp(start, end, ping_pong(number, pingpong_amount))
	number += delta

func ping_pong(number, pingpong):
	var length = 2*pingpong
	var value = number
	while value > length:
		value -= length
	if value > pingpong:
		return pingpong-(value-pingpong)
		return value