持续的敌人对玩家的伤害 - Unity 2019.1 Beta

Question

Basically I have an enemy and a player. When the enemy or player bump into one one-another, the damage occurs and the player is injured resulting in a loss of HP. However, once contact is made, it only damages one time. How to I go about insuring that damage is being dealt to the player non-stop over the duration of the entire length of the collision?

I am setting up a bool variable isTouching and setting it to true on contact. then set a while loop up that will constantly decrement the player's HP. Then use OnCollisionExit to set the isTouching to false.

private bool isTouching; // determines if the player is 
touching
private void OnCollisionEnter2D(Collision2D collision)
{
    isTouching = true;


        if (collision.gameObject.tag == "Enemy01")
        {
        while (isTouching == true)
        {
            GetComponent<AudioSource>().Play();
            HPBAR.PlayHP -= Random.Range(5, 30);
            if (HPBAR.PlayHP < 0)// Insures player HP bar doesn't read less 
            than zero in GUI TXT
            {
                HPBAR.PlayHP = 0;

            }
            // Debug.Log("Ouch! " + HPBAR.PlayHP + " Left");
            if (HPBAR.PlayHP <= 0 && HPBAR.lives > 0)
            {

                HPBAR.lives--;
                HPBAR.LPfloat--;
                p5.transform.position = spawner.transform.position;
                HPBAR.PlayHP = Random.Range(100, 150);
                // Debug.Log("You're Dead!!! Lives left: " + (HPBAR.lives + 1));

            }
            else if (HPBAR.PlayHP <= 0 && HPBAR.lives <= 0)
            {

                SceneManager.LoadScene("DeathScene");

            }
        }//end of while


        } // of player tag check

}// end of collision enter

private void OnCollisionExit2D(Collision2D collision)
{
    isTouching = false;
}

The while loop freezes my computer so I Don't recommend you running it with the while loop on there. Anyway, what I need to know is how to achieve what I'm trying to do. How can I make the enemy constantly damage the player? For example, if I jump on top of the enemy, it'll damage one time then I can ride him around. Which I want damage non-stop to force the player to move off or die eventually.

Answer 1

OnCollisionEnter2D is meant to trigger only the first frame the same collision occurs.

You want to use OnCollisionStay2D() , which triggers on every frame with a collision.

Also, get rid of the while loop. The game can't update (including calling OnCollisionExit2D ) until the method terminates.

private void OnCollisionStay2D(Collision2D collision)
{
    if (collision.gameObject.tag == "Enemy01")
    {
        GetComponent<AudioSource>().Play();

        // To take 5 - 30 damage per second:
        HPBAR.PlayHP -= Random.Range(5f,30f) * Time.deltaTime;

        if (HPBAR.PlayHP < 0)// Insures player HP bar doesn't read less than zero in GUI TXT
        {
            HPBAR.PlayHP = 0;

        }
        // Debug.Log("Ouch! " + HPBAR.PlayHP + " Left");
        if (HPBAR.PlayHP <= 0 && HPBAR.lives > 0)
        {
            HPBAR.lives--;
            HPBAR.LPfloat--;
            p5.transform.position = spawner.transform.position;
            HPBAR.PlayHP = Random.Range(100, 150);
            // Debug.Log("You're Dead!!! Lives left: " + (HPBAR.lives + 1));

        }
        else if (HPBAR.PlayHP <= 0 && HPBAR.lives <= 0)
        {
            SceneManager.LoadScene("DeathScene");
        }

    } // of player tag check

}// end of collision stay

private void OnCollisionExit2D(Collision2D collision)
{
    if (collision.gameObject.tag == "Enemy01")
    {
        // put "i quit touching the hurty thing" stuff here.
    }
}