Unity note

What is a Coroutine?

Unity - Manual: Coroutines

定義: A method which can suspend ( otherwise known as yield ) its execution until the yield instructions you gave it are met.
( So yield is another way of saying give back or relinquish or suspend.)

用處: A useful approach for us to allow our game to wait for something to happen or to not continue until some other conditions are met.

例如:當玩家血歸0，call KillPlayer coroutine (執行以下動作):

• Trigger the death animation

• Yield (wait) for three seconds.

• Restart the level.

如果沒有Yield 會馬上Restart the level。

 

如何使用:
1. Startcoroutine(NameofCoroutine()) : call Coroutine的方法

2.

    IEnumerator NameOfCoroutine()
    {
        //A thing to do
        yield return SomeCondition // yield return until something is met
        //B thing to do
    }

IEnumerator 像是 void、int 是一種 return type。

SomeCondition : 可以用 new WaitForSconds(3);

流程: 執行A(yield return 前的敘述) -> 等條件發生 -> 執行B(yield return 後的敘述)

停止方式:
 

Coroutine firingCoroutine;
firingCoroutine = StartCoroutine(FireContinuously());

//方法一
StopAllCoroutines();

//方法二
StopCoroutine(firingCoroutine);

 

哪時可以用?
1. 需要等一段時間後才發生的事。例如:Laser Defender 的連續發射的間隔時間。
詳細作法連結

 

 

其他補充:淺談 Unity Coroutine 的運行方式