IEnumerator GenerateTrashDebris(int level)
{
List <Debris> trash = new List <Debris>();
if (trash.Count > 0)
{
throw new UnityException("Trash was not empty");
}
Debris.trash = new List <Debris>();
for (int i = 0; i < trash_debris_num[level]; i++)
{
Debris d = Instantiate(debris_prefab);
d.persistent = false;
trash.Add(d);
}
Debris.trash.AddRange(trash);
foreach (Debris d in trash)
{
d.Initialize();
yield return(new WaitForSeconds(generate_delay[level] / 2f));;
d.Fly();
}
trash_routine = null;
}