Color.Lerp not changing?

Questions & Answers
1

My gun uses an overheating system rather than ammo. To relay this to the player, I have a red light and a green light on the gun. I’m trying to change the opacity of the lights based on the heat level. So far, I have the red color changing perfectly in the script, it just doesn’t change the actual material in-game. I’ve tried everything I can thing of and searched Ask Unity for ages but haven’t found a solution. Here’s the code:

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

public class SimpleShoot : MonoBehaviour
{

    public GameObject bulletPrefab;
    public GameObject casingPrefab;
    public GameObject muzzleFlashPrefab;

    public Transform barrelLocation;
    public Transform casingExitLocation;

    private bool Cooldown;
    private bool NeedsToCharge;
    public bool Fire;

    public float Delay;
    public float RechargeTime;
    public float Heat;
    public float HeatToIncrease;
    public float speed;
    public float shotPower = 100f;

    private Material Green;
    private Material Red;

    public GameObject GreenMesh;
    public GameObject RedMesh;

    public Color GreenColor;
    public Color RedColor;

    void Start()
    {
        Cooldown = true;

        Green = GreenMesh.GetComponent<SkinnedMeshRenderer>().material;
        Red = RedMesh.GetComponent<SkinnedMeshRenderer>().material;

        if (barrelLocation == null)
            barrelLocation = transform;
    }

    void Update ()
    {
        if (Fire == true)
        {
            Shoot();
        }

        if (Heat > 1)
        {
            StartCoroutine(Recharge());
        }

        RedColor.a = Heat;

        if (Red.color != RedColor)
        {
            Red.color = Color.Lerp(Red.color, RedColor, Time.deltaTime * speed);
        }

    }

    public void StartShoot ()
    {
        GetComponent<Animator>().SetBool("Fire", Fire);
    }

    void Shoot()
    {
        if (Cooldown == true && NeedsToCharge == false)
        {
            StartCoroutine(ShootDelay());
        }
    }

    void CasingRelease()
    {
         GameObject casing;
        casing = Instantiate(casingPrefab, casingExitLocation.position, casingExitLocation.rotation) as GameObject;
        casing.GetComponent<Rigidbody>().AddExplosionForce(550f, (casingExitLocation.position - casingExitLocation.right * 0.3f - casingExitLocation.up * 0.6f), 1f);
        casing.GetComponent<Rigidbody>().AddTorque(new Vector3(0, Random.Range(100f, 500f), Random.Range(10f, 1000f)), ForceMode.Impulse);
    }

    public IEnumerator ShootDelay ()
    {
        Cooldown = false;
        yield return new WaitForSeconds(Delay);
        GameObject tempFlash;
        Instantiate(bulletPrefab, barrelLocation.position, barrelLocation.rotation).GetComponent<Rigidbody>().AddForce(barrelLocation.forward * shotPower);
        tempFlash = Instantiate(muzzleFlashPrefab, barrelLocation.position, barrelLocation.rotation);
        Heat = Heat + HeatToIncrease;
        Cooldown = true;
    }

    public IEnumerator Recharge()
    {
        NeedsToCharge = true;
        yield return new WaitForSeconds(RechargeTime);
        Heat = 0;
        NeedsToCharge = false;
    }


}

Extra info: I’m using Nokobot’s modern handgun asset from the Asset Store. It’s a VR game so displaying the heat meter via UI is off the table.

3

Update! It turns out, the issue was because I was using Lightweight Render Pipeline and materials are handled differently. I found a tutorial on how to Lerp Lightweight materials and got everything working now!

2

Your problem is with how you’re using Lerp.

Red.color = Color.Lerp(Red.color, RedColor, Time.deltaTime * speed);

Lerp sets the value between the two colours based on the third value, with 0 being fully the first colour, and 1 being the second. Time.deltaTime doesn’t really change between frames in most cases, so you’re always setting this Lerp to the same value every frame.

You want to add Time.deltaTime to a variable every frame, and use that variable in your Lerp.