Lerp from old value to new value on same variable.

Questions & Answers
1

The other answers page with a similar question wasn’t answered for me as I have different (slightly) circumstances. With mine , here’s a problem.
I’m constantly updating my HEALTHUI (FillAmount) for UI with the actual health amount divided by 10.
What I would like to do is this:
HealthUI.fillAmount = Mathf.Lerp(Health/10, Health/10, Time.DeltaTime * Smooth);
For it to Lerp between old health value to new health value using the same variable?

2

How would you like an over-engineered and untested solution?

public class LerpVariable
{
    float lerpTime = 0;
    float targetValue;
    float? currentValue;

    public float Value
    {
        get
        {
            return (currentValue.HasValue)
                ? Mathf.Lerp(currentValue.Value, targetValue, lerpTime)
                : 0;
        }
    }

    public float TargetValue
    {
        get { return targetValue; }
        set
        {
            if (currentValue.HasValue == false)
            {
                currentValue = value;
            }
            else
            {
                currentValue = Value;
            }

            lerpTime = 0;
            targetValue = value;
        }
    }

    public void UpdateValue()
    {
        lerpTime = Mathf.Clamp(lerpTime + Time.deltaTime, 0, 1);
    }
}

Usage:

LerpVariable Health = new LerpVariable();

if (isHealing && Health.TargetValue < 100)
{
    Health.TargetValue = Health.TargetValue + (0.1f * Time.deltaTime);
}

if (wasShot)
{
    Health.TargetValue -= 40;
}

UpdateHealthBar(Health.Value);