koobas.hobune.stream
How to avoid Synchronous Script Behaviour
Hey guys,
I am having problem in building a clone for Space Invaders 1978. My game has 11 columns with 5 rows of aliens. The column has a script that checks for the 1st alien in the row and allows it to fire. The problem is that each column is behaving synchronously with other column scripts Example: if column1 fires a bullet, Column2-11 can't fire until Column1's bullet is finished, I want a asynchronous behave such that no columns are dependent on one another.
The ColumnScript is as:
public float min = 0;
public float max = 10;
void Start () {
float rand = Random.Range (min, max);
Invoke ("SelectForFire", rand);
}
void SelectForFire () {
if (transform.childCount > 0) {
transform.GetChild (0).gameObject.GetComponent<EnemyScript> ().Invoke ("Fire", 0f);
float rand = Random.Range (min, max/2);
Invoke ("Start", rand);
}
}
and the EnemyScript as:
public Rigidbody2D bullet;
void Fire () {
float x = transform.position.x;
float y = transform.position.y - 0.4f;
Instantiate (bullet, new Vector2 (x, y), Quaternion.identity);
}
How can I fix this?
Just to be clear here about the object tree you have here (because I have a suspicion, but we have to confirm it) what you have in your scene is something like:
Column A
Alien 1
Alien 2
Alien 3
Alien 4
Alien 5
Column B
Alien 1
Alien 2
Alien 3
Alien 4
Alien 5
Column C
Alien 1
Alien 2
...
Column D ...
Where each Column is a transform with the first code assigned as a behavior, correct?
@brazmogu It means that void OnBecameInvisible is called when the bullet leaves the camera and destroys it via Destroy(gameObject)
I don't see the dependency you're talking about. when every column has it's ColumnScript, how should they be able to prevent one another to do something? I can't see that happening
So, assuming everything else is in order, the only thing I'm not very familiar with here is the use of Invoke. The docs state it's as simple as a delayed "SendMessage", but the impression I'm getting is that it's less asynchronous that it seems.
Point in case, you could do this with co-routines instead. So the code for your ColumnScript becomes
public float min = 0;
public float max = 10;
void Start () {
float rand = Random.Range (min, max);
StartCoroutine (SelectForFire (rand) );
}
IEnumerator SelectForFire (float delay) {
yield return new WaitForSeconds(delay);
if (transform.childCount > 0) {
transform.GetChild (0).gameObject.GetComponent<EnemyScript> ().SendMessage ("Fire");
float rand = Random.Range (min, max/2);
yield return SelectForFire (rand);
}
}
and EnemyScript would be like:
public Rigidbody2D bullet;
void Fire () {
float x = transform.position.x;
float y = transform.position.y - 0.4f;
Instantiate (bullet, new Vector2 (x, y), Quaternion.identity);
}
