GUI Question please help.

Hello, this is a AAA production so take that in mind first.

The HUD effect is made with a tweening operation, maybe from code.

I did it myself more humble with NGui plugin, it has a Tween Component that i applied to my HUD that i trigger on crash.

This should't be too complicated. First you need to define how you want to the HUD to move. For instance, you can say, if my player is jumping, I want the HUD to tilt slightly down while he is doing so. Now you can check your PlayerController and look at if the player is gounded or not, if it is not, you can tween the hud a few pixels down, and as soon as the player is grounded again, you can tilt it a few pixels up.

Assuming you are using a (proper) GUI framework, like NGUI, the simplest way would be to add a reference to the HUD gameobject to your PlayerController script. In the update function of your PlayerController you could do something like (the following code is untested, just wrote it here in the editor):

 public Gameobject hud;
 
 private bool hudIsShaking = false;
 private const float shakeDuration = 0.5f;
 
 void FixedUpdate(){
  /* ...
   .... */
   Vector3 direction = new Vector3(0.0f, 1.0f;, 0.0f);
   if (!grounded && !hudIsShaking){
       hudIsShaking = true;
       StartCoroutine(TweenHud(direction));
   }else if (grounded && hudIsShaking){
       hudIsShaking = false;
       StartCoroutine(TweenHud(direction * -1f));
  }
 }
 
 IEnumerator TweenHud(Vector3 direction){
   float duration = 0.0f;
   Vector3 hudInitialPosition = hud.transform.position;
   Vector3 hudTargetPosition = hudInitialPosition + direction;
   while (duration < shakeDuration){
       duration += Time.deltaTime;
       hud.transform.position = Vector3.Lerp(hudInitialPosition, hudTargetPosition, duration / shakeDuration);
       yield return null; 
   }
 }