DelayedAgendaItem : AgendaItem

[Previous] [Main] [Next]

A DelayedAgendaItem, as its name suggests, is an AgendaItem that becomes active at some point in the future. As with ConvAgendaItem this relies on an overridden isReady method, so that if you want to add your own isReady condition this needs to be combined with the inherited behaviour.

In addition to the properties it inherits from AgendaItem, DelayedAgendaItem has a readyTime property which is used to determine when it will become active, and a setDelay(turns) method which is used to set readyTime the desired number of turns in the future; the setDelay method returns self (for reasons that will shortly become apparent).

For example, suppose we want a pair of demons to make a threatening advance on the player character (PC) two turns after the PC arrives in their vicinity (assuming that the PC remains in their vicinity). The usefulness of the delay in this case is that the demons' sudden outburst is rather less predictable to the player if it doesn't come on the same turn that the player first encounters the demons. First we can define an appropriate DelayedAgendaItem, which should be located in the demons object:

+ demonsHissing : DelayedAgendaItem
  isReady = (inherited && getActor.canSee(gPlayerChar))
  invokeItem
  {
    "Two of the demons suddenly spring towards you, hissing wildly and
     pawing at you with their claws. <q>Despair, human, despair!</q> they
     shriek, <q>Your time is running out!</q> ";
     isDone = true;
  }
;

Next we want some means of setting this to run two turns after the PC encounters the demons. The best way to do this is probably to add demonsHissing to the demonic agenda in demonsPrancing.afterTravel:

++ demonsPrancing : ConversationReadyState
  specialDesc = "A gaggle of demons is prancing around on the rocks near the steps down
   towards the basalt plain, pretending to ignore you, but keeping a careful watch on
   you just the same. "
  stateDesc = "They're prancing around near the steps down to the plain. "
  isInitState = true
  beforeTravel(traveler, connector)
  {
    if(connector == hellPathDown)
    {
      "The demons bunch together and shriek at you, driving you back from the steps. ";
      exit;
    }
    inherited(traveler, connector); 
  }
  afterTravel(traveler, connector)
  {
    getActor.addToAgenda(demonsHissing.setDelay(2));
  }
;

Now we can see the advantage of having setDelay() return self. This allows us to do in one statement what we should otherwise have to do in two, since

getActor.addToAgenda(demonsHissing.setDelay(2));

is equivalent to

  demonsHissing.setDelay(2);
  getActor.addToAgenda(demonsHissing);