AppleHillsProduction/Assets/Scripts/DamianExperiments/DivingForPicturesMinigame/FlashBehaviour.cs

using UnityEngine;
using System.Collections;

public class FlashBehaviour : MonoBehaviour
{
    public GameObject square; // Assign in inspector or find in Start
    public float flashInDuration = 0.05f;
    public float flashOutDuration = 0.2f;

    private Color squareColor;
    private Coroutine flashCoroutine;
    private SpriteRenderer spriteRenderer;

    void Start()
    {
       
        if (square == null)
            square = transform.Find("Square")?.gameObject;

        if (square != null)
            spriteRenderer = square.GetComponent<SpriteRenderer>();

        if (spriteRenderer != null)
        {
            squareColor = spriteRenderer.color;
            squareColor.a = 0;
        }
        
    }

    public void TriggerFlash()
    {
        if (flashCoroutine != null)
            StopCoroutine(flashCoroutine);
        flashCoroutine = StartCoroutine(FlashRoutine());
    }

    private IEnumerator FlashRoutine()
    {
        // Fade in
        float t = 0;
        while (t < flashInDuration)
        {
            t += Time.deltaTime;
            SetAlpha(Mathf.Lerp(0, 1, t / flashInDuration));
            yield return null;
        }
        SetAlpha(1);

        // Fade out
        t = 0;
        while (t < flashOutDuration)
        {
            t += Time.deltaTime;
            SetAlpha(Mathf.Lerp(1, 0, t / flashOutDuration));
            yield return null;
        }
        SetAlpha(0);
    }

    private void SetAlpha(float alpha)
    {
        if (spriteRenderer != null)
        {
            squareColor.a = alpha;
            spriteRenderer.color = squareColor;
        }
    }
}