ActorStateclass
An ActorState represents the current state of an Actor.
The main thing that makes actors special is that they’re supposed to be living, breathing people or creatures. That substantially complicates the programming of one of these objects, because in order to create the appearance of animation, many things about an actor have to change over time.
The ActorState is designed to make it easier to program this variability that’s needed to make an actor seem life-like. The idea is to separate the parts of an actor that tend to change according to what the actor is doing, moving all of those out of the Actor object and into an ActorState object instead. Each ActorState object represents one state of an actor (i.e., one thing the actor can be doing). The Actor object becomes easier to program, because we’ve reduced the Actor object to the character’s constant, unchanging features. The stateful part is also easier to program, because we don’t have to make it conditional on anything; we simply define all of the stateful parts in an ActorState, and we define separate ActorState objects for the different states.
For example, suppose we want a shopkeeper actor, whose activities include waiting behind the counter, sweeping the floor, and stacking cans. We’d define one ActorState object for each of these activities. When the shopkeeper switches from standing behind the counter to sweeping, for example, we simply set the “curState” property in the shopkeeper object so that it points to the “sweeping” state object. When it’s time to stack cans, we change “curState” to it points to the “stacking cans” state object.
class ActorState : TravelMessageHandler ActorTopicDatabase
Superclass Tree (in declaration order)
ActorState
TravelMessageHandler
` object
[ActorTopicDatabase](../object/ActorTopicDatabase.html)
[TopicDatabase](../object/TopicDatabase.html)
object`
Subclass Tree
ActorState
AccompanyingInTravelState
GuidedInTravelState
AccompanyingState
GuidedTourState
ConversationReadyState
HermitActorState
InConversationState
Global Objects
(none)
Summary of Properties
autoSuggest getImpliedConvState isInitState location stateDesc stateSuggestedTopics
Inherited from ActorTopicDatabase :
askForTopics askTopics commandTopics giveTopics initiateTopics miscTopics showTopics specialTopics tellTopics
Inherited from TopicDatabase :
limitSuggestions suggestedTopics topicGroupActive topicGroupScoreAdjustment
Summary of Methods
activateState afterAction afterTravel arrivingTurn arrivingWithDesc beforeAction beforeTravel construct deactivateState distantSpecialDesc endConversation getActor getNominalTraveler getSuggestedTopicList getTopicOwner handleConversation initializeActorState justFollowed notifyTopicResponse obeyCommand remoteSpecialDesc showSpecialDescInContents specialDesc specialDescListWith suggestTopicsFor takeTurn
Inherited from TravelMessageHandler :
sayArriving sayArrivingDir sayArrivingDownStairs sayArrivingLocally sayArrivingThroughPassage sayArrivingUpStairs sayArrivingViaPath sayDeparting sayDepartingDir sayDepartingDownStairs sayDepartingLocally sayDepartingThroughPassage sayDepartingUpStairs sayDepartingViaPath sayTravelingRemotely
Inherited from ActorTopicDatabase :
initiateTopic showTopicResponse
Inherited from TopicDatabase :
addSuggestedTopic addTopic addTopicToList compareVocabMatch findTopicResponse handleTopic removeSuggestedTopic removeTopic removeTopicFromList showSuggestedTopicList
Properties
autoSuggest
Should we automatically suggest topics when the player greets our actor? By default, we show our “topic inventory” (the list of currently active topics marked as “suggested”). This can be set to nil to suppress this automatic suggestion list.
Some authors might not like the idea of automatically suggesting topics every time we greet a character, but nonetheless wish to keep the TOPICS command as a sort of hint mechanism. This flag can be used for this purpose. Authors who don’t like suggested topics at all can simply skip defining any SuggestedTopic entries, in which case there will never be anything to suggest, rendering this flag moot.
getImpliedConvState
Get my implied in-conversation state. This is used when our actor initiates a conversation without specifying a particular conversation state to enter (i.e., actor.initiateConversation() is called with ‘state’ set to nil). By default, we don’t have an implied conversation state, so we just return ‘self’ to indicate that we want to stay in the current state. States that are coupled with separate in-conversation states, such as ConversationReadyState, should return their associated conversation states here.
isInitState
Is this the actor’s initial state? If so, we’ll automatically set the actor’s curState to point to ‘self’ during pre-initialization. For obvious reasons, this should be set to true for only one state for each actor; if multiple states are all flagged as initial for the same actor, we’ll pick on arbitrarily as the actual initial state.
location
The ‘location’ is the actor that we’re associated with.
ActorState objects aren’t actual simulation objects, so the ‘location’ property isn’t used for containment. For convenience, though, use it to indicate which actor we’re associated with; this lets us use the ‘+’ notation to define the state objects associated with an actor.
stateDesc
Our “state” description. This shows information on what the actor is *currently* doing; we display this after the static part of the actor’s description on EXAMINE <ACTOR>. By default, we add nothing here, but state objects that represent scripted activies should override this to describe their scripted activities.
stateSuggestedTopics
get the topic suggestions for this state - by default, we just return our own suggestedTopics list
Methods
activateState (actor, oldState)
Activate the state - this is called when we’re about to become the active state for an actor. We do nothing by default.
afterAction ( )
handle an after-action notification for our actor
afterTravel (traveler, connector)
handle an after-travel notification
arrivingTurn ( )
Perform any special action on a group-travel arrival. When group travel is performed using the AccompanyingInTravelState class, this is essentially called in lieu of the regular takeTurn() method on the state that is coming into effect after the group travel. (Not really, but effectively: the accompanying travel state will still be in effect, so its takeTurn() method is what’s really called, but that method will call this method explicitly.) By default, we do nothing. Since this runs on our turn, it’s a good place to put any scripted behavior we perform on arriving at our new destination after the group travel.
arrivingWithDesc ( )
Our group-travel arrival description. By default, when we perform an accompanying travel with another actor as the lead actor, the accompanying travel state will display this message instead of our specialDesc when the lead actor first arrives in the new location. We’ll just display our own specialDesc by default, but this should usually be overridden to say something specific to the group travel arrival. The actual message is entirely dependent on the nature of the group travel, which is why we don’t provide a special message by default.
For scripted behavior, it’s sometimes better to use arrivingTurn() rather than this method to describe the behavior. arrivingWithDesc() is called as part of the room description, so it’s best for any message shown here to fit well into the usual room description format. For more complex transitions into the new room state, arrivingTurn() is sometimes more appropriate, since it runs like a daemon, after the arrival (and thus the new room description) is completed.
beforeAction ( )
Handle a before-action notification for our actor. By default, we do nothing.
beforeTravel (traveler, connector)
handle a before-travel notification
construct (actor)
no description available
deactivateState (actor, newState)
Deactivate the state - this is called when we’re the active state for an actor, and the actor is about to switch to a new state. We do nothing by default.
distantSpecialDesc ( )
show the special description for the actor at a distance
endConversation (actor, reason)
End the current conversation. ‘reason’ indicates why we’re leaving the conversation - this is one of the endConvXxx enums defined in adv3.h. beforeTravel() calls this automatically when the other party is trying to depart, and they’re talking to us.
This returns true if we wish to allow the conversation to end, nil if not.
getActor ( )
Get the actor associated with the state - this is simply the ‘location’ property. If we’re nested inside another ActorState, then our actor is our enclosing ActorState’s actor.
getNominalTraveler ( )OVERRIDDEN
For our TravelMessageHandler implementation, the nominal traveler is our actor. Note that this is all we need to implement for travel message handling, since we simply inherit the default handling for all of the arrival/departure messages.
getSuggestedTopicList ( )
Get our suggested topic list. The suggested topic list consists of the union of the current ConvNode’s suggestion list, the ActorState list, and the Actor’s suggestion list. In each case, the suggestion list is the list of all SuggestedTopic objects at each database level.
The suggestions are arranged in a hierarchy, and each hierarchy level can prevent suggestions from a lower level from being included. The top level of the hierarchy is the ConvNode; the next level is the ActorState; and the last level is the Actor. Suggestions are limited at each level with the ‘limitSuggestions’ property: if true, suggestions from lower levels are not included.
getTopicOwner ( )OVERRIDDEN
the owner of any topic entries within the state is just my actor
handleConversation (otherActor, topic, convType)
General conversation handler. This can be used to process most conversational commands - ASK, TELL, GIVE, SHOW, etc. The standard sequence of processing is as follows:
- If our actor has a non-nil current conversation node (ConvNode) object, and the ConvNode wants to handle the event, let the ConvNode handle it.
- Otherwise, check our own topic database to see if we can find a TopicEntry that matches the topic; if we can find one, let the TopicEntry handle it.
- Otherwise, let the actor handle it.
‘otherActor’ is the actor who originated the conversation command (usually the player character). ‘topic’ is the subject being discussed (the indirect object of ASK ABOUT, for example). convType’ is a ConvType describing the type of conversational action we’re performing.
initializeActorState ( )
initialize the actor state
justFollowed (success)
Receive notification that we just followed another actor as part of our programmed following behavior (in other words, due to our ‘followingActor’ property, not due to an explicit FOLLOW command directed to us). ‘success’ is true if we ended up in the actor’s location, nil if not.
This can be used to update the actor’s state after a ‘follow’ operation occurs; for example, if the actor’s state depends on the actor’s location, this can update the state accordingly. We don’t do anything by default.
notifyTopicResponse (fromActor, entry)
Receive notification that a TopicEntry is being used (via its handleTopic method) to respond to a command. The TopicEntry will call this before it shows its message or takes any other action. By default, we do nothing.
obeyCommand (issuingActor, action)
Should we obey an action? If so, returns true; if not, displays an appropriate response and returns nil. This will only be called when the issuing actor is different from our actor, since a command to oneself is implicitly always obeyed.
remoteSpecialDesc (actor)
show the special description for the actor in a remote location
showSpecialDescInContents (actor, cont)
show the special description when we appear in a contents listing
specialDesc ( )
Show the special description for the actor when the actor is associated with this state. By default, we use the actor’s actorHereDesc message, which usually shows a generic message (something like “Bob is here” or “Bob is sitting on the chair”) to indicate that the actor is present.
States representing scripted activities should override these to indicate what the actor is doing: “Bob is sweeping the floor,” for example.
specialDescListWith ( )
The list group(s) for the special description. By default, if our specialDesc isn’t overridden, we’ll keep this in sync with the specialDesc by returning our actor’s actorListWith. And if specialDesc *is* overridden, we’ll just return an empty list to indicate that we’re not part of any list group. If you want to provide your own listing group special to the state, simply override this and speicfy the custom list group.
suggestTopicsFor (actor, explicit)
Suggest topics for the given actor to talk to us about. This is called when the given actor enters a TOPICS command (in which case ‘explicit’ will be true) or enters a conversation with us via TALK TO or the like (in which case ‘explicit’ will be nil).
takeTurn ( )
Take a turn. This is called when it’s the actor’s turn and there’s not something else the actor needs to be doing (such as following another actor, or carrying out a command in the actor’s pending command queue).
By default, we perform several steps automatically.
First, we check to see if the actor is in a ConvNode. If so, the ConvNode takes precedence. If we haven’t been addressed already in conversation on this turn, we’ll let the ConvNode perform its “continuation,” which lets the NPC advance the conversation of its own volition. In any case, if we have a current ConvNode, we’re done with the turn, since we assume the actor will want to proceed with the conversation before pursuing its agenda or performing a background action.
Second, assuming there’s no active ConvNode, we check for an “agenda” item that’s ready to execute. If we find one, we execute it, and we’re done. The agenda item takes precedence over any other scripting we might have.
Finally, if we also inherit from Script, and we didn’t find an active ConvNode or an agenda item that was ready to execute, we invoke our doScript() method. This makes it especially easy to define random background messages for the actor - just add an EventList class (ShuffledEventList is usually the right one) to the state’s superclass list, and define a list of background message strings.
TADS 3 Library Manual
Generated on 5/16/2013 from TADS version 3.1.3