如何为我在统一 2d 中的跳跃设置冷却时间？ [找到答案]

Question

I'm making a 2D platformer game. Everything is working out well except for the jump. The character jumps normally but the problem is there is no cooldown and I can basically jump infinitely. Can someone please tell me how I can make a cooldown? Thanks. (I'm new to C# and Unity)

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

public class MovingWithJump : MonoBehaviour
{

    public float speed;
    public float jump;
    public float cooldownTime;
    private float nextFireTime;
    private float move;
    private Rigidbody2D rb;
    private float jump_start_time = 0f;
    private float elapsed_jump_time = 0f;
    // Start is called before the first frame update
    void Start()
    {
       rb = GetComponent<Rigidbody2D>(); 
    }

    // Update is called once per frame
    void Update()
        
    {
        if(Input.GetButtonDown("Jump") && elapsed_jump_time > 1f) {
            rb.AddForce(new Vector2(rb.velocity.x, jump));
            jump_start_time = Time.time;
        }
        elapsed_jump_time = Time.time - jump_start_time;
       move = Input.GetAxis("Horizontal");

       rb.velocity = new Vector2(move * speed, rb.velocity.y);
       if(Input.GetButtonDown("Jump")) {
           rb.AddForce(new Vector2(rb.velocity.x, jump));
           
       }
    }
}

Answer 1

You can check the elapsed time since the jump to jump or not. Find the example for 2 seconds cooldown. I did not debug that, but you can get the idea.

private float jump_start_time = 0f;
private float elapsed_jump_time = 0f;

if(Input.GetButtonDown("Jump") && elapsed_jump_time > 2f) {
    rb.AddForce(new Vector2(rb.velocity.x, jump));
    jump_start_time = Time.time;         
}
elapsed_jump_time = Time.time - jump_start_time;

Answer 2

The easy way would be to include a boolean variable (true/false) and do a check to see i the boolean is true or not.

For that to work though, you'll need to connect to the colliders in Unity.

So -

private bool isJumping;
public float speed;
public float jump;
public float cooldownTime;
private float nextFireTime;
private float move;
private Rigidbody2D rb;
// Start is called before the first frame update
void Start()
{
   rb = GetComponent<Rigidbody2D>(); 
}

// Update is called once per frame
void Update()
    
{
    
   move = Input.GetAxis("Horizontal");

   rb.velocity = new Vector2(move * speed, rb.velocity.y);
   if((Input.GetButtonDown("Jump")) && !isJumping) {
       rb.AddForce(new Vector2(rb.velocity.x, jump));
       isJumping = true;
   }
   
}

After that though, you need a way to turn the boolean false. Because otherwise, you'll jump once, and never jump again. So you need to grab the collider for the ground (or other similar object, preferably all on one layer) and when the onCollision triggers you can set the isJumping boolean to false.

Answer 3

Add cooldown

    public KeyCode JUMP_KEY;
    public const float COOLDOWN_TIME = 2.0f; 
    private float _cooldown;


    void Update(){
        _cooldown-= Time.deltaTime;
        if(Input.GetKey(JUMP_KEY) && Cooldown <= 0) {
            //TODO : JUMP which you want
            //Reset cooldown time
            _cooldown = COOLDOWN_TIME;
        }
    }

Detect Platform Collider

by adding a small trigger area under the character to detect it on ground or not. I prefer to create a new component like this

public class PlatformCollider : MonoBehaviour {
    public bool OnGround {get; private set;}

    private void OnTriggerEnter2D(Collider2D collision) {
        if(collision.tag == "ground") {
            OnGround = true;
        }
    }

    private void OnTriggerExit2D(Collider2D collision) {
        if(collision.tag == "ground") {
            OnGround = false;
        }
    }

}

When implement with 2 way above You will get JumpController class like this

public class JumpController : MonoBehaviour
{
    public PlatformCollider GroundTrigger;
    
    public KeyCode JUMP_KEY;
    public const float COOLDOWN_TIME = 2.0f;
    private float _cooldown;
    
    void Update(){
        _cooldown -= Time.deltaTime;
        if(Input.GetKey(JUMP_KEY) && GroundTrigger.OnGround && _cooldown <= 0) {
            //TODO : JUMP which you want
            //Reset cooldown time
            _cooldown = COOLDOWN_TIME;
        }
    }
    
}