Apply vertical Force then return it to Zero on release Key

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1

Hi, im having some troubles I have a swimming style game where the player moves forward, up and down, i’m applying forces to a rigidbody in order to move the player more naturally the aceleration is working fine, the thing is when i want to move up or down the player moves but the velocity of the rigidbody remains, i mean it keeps moving vertically, but i want it to only move a little bit more when the user releases the key, not to keep moving vertically at a constant speed.

Here’s the code im applying to the movement, everything is succesfully called from FixedUpdate() and input from Update()

	void FixedUpdate ()
    {
        if (isPlayer)
        {
            if (up && !down)
                Subir();

            if (down && !up)
                Bajar();

        }
    }

 public void Subir()
    {
        rigidbody.AddForce(Vector3.up * VerticalVelocity,ForceMode.Force);
    }

    public void Bajar()
    {
        rigidbody.AddForce(Vector3.down * VerticalVelocity,ForceMode.Force);
    }

i’m changing the up and down variables from the Input on the update. i think is not necessary to show it, the problem is if there’s some way to slowly decelerate the Y velocity of the rigidboy to Zero when the user releases the key.
I’ve already tried with different ForceMode, Impulse,Acceleration,Force, etc… without any result.

3

Hi, thanks, i managed to do this in another way, without directly altering the velocity of the rigidbody, it seems more natural, here’s the code:

             if (rigidbody.velocity.y != 0)
        {
            if (!up && !down)
            {
                if (rigidbody.velocity.y > 0)
                {
                    rigidbody.AddForce(new Vector3(0, -rigidbody.velocity.y*2f, 0));
                }
                else if (rigidbody.velocity.y < 0)
                {
                    rigidbody.AddForce(new Vector3(0, rigidbody.velocity.y*-2f, 0));
                }
            }
        }

anyway thanks.

2

As robertbu said, the general idea behind his code snippet should work, however I’d add some safety checks.

if (!up && !down)
  {
    //No point in doing this if the body is already still   
    if(rigidbody.velocity != 0)
      {
        //Multiplying by 0.9 will never result in 0, the value
        //will just get smaller and smaller. So we set it to 0
        //manually when its small enough. In this case 2.
        if(rigidbody.velocity > 2)
          rigidbody.velocity *= 0.9;
        else
          rigidbody.velocity = 0;
      }
  }