Vector2.Lerp sizes instantly

Unity Engine
1

Hello, I’m trying to make an exp bar scale smoothly using lerp. When the player gains exp though the bar scales instantly even though I’m using lerp.

Here is a gif of the bar and the script
https://gyazo.com/13f94f3642f736cfe2908462b1f0b17d

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class Exp : MonoBehaviour
{
    //Stats
    public float minExp;
    public float maxExp;
    public float exp;
    private float minWidth = 250;
    private float maxWidth = 1509;
    private float width;
    [SerializeField]
    private float lerpSpeed;
    //Components
    public RectTransform bar;

    void Start()
    {
        UpdateBar();
    }
    public void UpdateBar()
    {
        exp = Mathf.Clamp(exp, minExp, maxExp);
        width = (exp / maxExp) * (maxWidth - minWidth) + minWidth;
        bar.sizeDelta = Vector2.Lerp(bar.sizeDelta, new Vector2(width, bar.sizeDelta.y), lerpSpeed);
    }
}
2

Lerp will do whatever you tell it to do.

If you pass a value >= 1 in the third parameter, it will return the second parameter you give it immediately.

If you give it .5 it will give you a value midway between the first and second parameters in a single frame.

Read this and make sure you understand what the Lerp function actually does Unity - Scripting API: Vector2.Lerp

Basically you’re using Lerp in a bit of a funky and framerate dependent way.

1 Like
3

to run it from Start, could use coroutine
http://answers.unity.com/answers/1502200/view.html

1 Like
4

Thank you for your replies, the problem is solved!
https://gyazo.com/647567f42d3ad697d9cecff205435ff4