nested coroutines and WaitForEndOfFrame

Scripting
1

hi
i call coroutine B() from first coroutine A()
in B(), i test 4 concurent positions of a gameObject Obj and would like to test for each position if obj is in collision with others objects : to test this, i have some other script with OnCollisionEnter () …

as OnCollisionEnter test rune once a frame, i tried to alternate each change of position with a call to WaitForEndOfFrame but it seems it appear this function do NOT wait for the end of frame and then collision fails

2
  1. What is your question?
  2. Probably need to show some code.
3

sorry … my question is : is it normal that function WaitForEndOfFrame DOT NOT wait for end of current frame when it is called from nested coroutines ( i call coroutine B() from first coroutine A() ) ?

Code looks like :
void Update() {
StartCoroutine(“A”);
}

IEnumerator A() {
…
StartCoroutine(“B”);
…
}

IEnumerator B() {
…
yield return new WaitForEndOfFrame(); / DO NO wait for end of frame
…
}

4

I honestly don’t know as I’ve never set up a set of calls like this, but it should work to wait till the end of whatever frame B is started in. Also what scenario are you wanting to do this? Update runs every frame and so you are starting a new coroutine every frame, thus you may not even notice if it’s waiting as you’re have a copy of A and B running every frame. You may be creating a ton of unneeded calls.

I know you tried to explain something above, but I really don’t understand what you are saying. You could just start a coroutine and have it loop, doing the yield within the loop and checking whatever you need it to check.

5

WaitForEndOfFrame is fine. Trouble is OnCollisionEnter doesn’t happen at the end of a frame.

This is wrong. OnCollisionEnter happens in FixedUpdate. Which can happen once, multiple times, or not at all in a frame frame. And if it happens, it happens at the start of a frame.

So try using WaitForFixedUpdate instead.

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