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

public class Ball : MonoBehaviour
{
    public float moveSpeed;
    private Rigidbody rb;
    public AudioClip coinGet;
    public float jumpSpeed;
    private bool isJumping = false;
    public int coinCount = 0;

    // ★追加
    public GameObject moveFloor;

    void Start()
    {
        rb = GetComponent<Rigidbody>();   
    }
    
    void Update()
    {
        float moveH = Input.GetAxis("Horizontal");
        float moveV = Input.GetAxis("Vertical");
        Vector3 movement = new Vector3(moveH, 0, moveV);
        rb.AddForce(movement * moveSpeed);

        if (Input.GetButtonDown("Jump") && isJumping == false)
        {
            rb.velocity = Vector3.up * jumpSpeed;
            isJumping = true;
        }
    }

    private void OnTriggerEnter(Collider other)
    {
        if (other.CompareTag("Coin"))
        {
            Destroy(other.gameObject);
            AudioSource.PlayClipAtPoint(coinGet, transform.position);

            coinCount += 1;

            // ★追加
            if (coinCount == 2)
            {
                // （ポイント）
                // SetActive()メソッドはオブジェクトをアクティブ／非アクティブ状態にすることができる。
                moveFloor.SetActive(true);
            }

            if (coinCount == 3)
            {
                SceneManager.LoadScene("GameClear");
            }
        }
    }
    
    private void OnCollisionEnter(Collision collision)
    {
        if(collision.gameObject.CompareTag("Floor"))
        {
            isJumping = false;
        }
    }
}
C#