Dialogue State

Whether the character is being spoken to, and whether it owes an answer. This is the lane that gives a character the one state it cannot infer from its own audio, which is Listening.

The Source

Implement IDialogueStateSource and assign it to the brain's DialogueStateSource.

Member	What it returns
bool IsListeningToSpeaker	Whether someone is currently speaking to this character
bool IsWaitingForPlayerResponse	Whether this character has finished and is waiting on the player

This is the interface a dialogue system implements once. It already knows who is talking to whom, and answering these two questions from that is usually a few lines. A shipped example, the simple dialogue state source under Examples, shows the whole of it as two switches a conversation flips.

Two Values, Each Its Own Lane

The two are overridden, released and owned separately. A cutscene can claim the listening lane without touching the waiting one, and each can be held by a different owner.

brain.SetListeningToSpeaker(this, true);
brain.SetWaitingForPlayerResponse(this, false);

Method	Does
SetListeningToSpeaker(bool)	Claims the anonymous lane
SetListeningToSpeaker(object owner, bool)	Claims it as this owner
ReleaseListeningToSpeakerOverride()	Gives back the anonymous lane
TryReleaseListeningToSpeakerOverride(object owner)	Gives it back only if this owner still holds it
ForceClearListeningToSpeakerOverride()	Takes it back regardless

WaitingForPlayerResponse has the same five, named the same way. ForceClearDialogueStateOverrides() clears both lanes at once.

Asking About It

Member	Tells you
IsListeningToSpeaker	The resolved value, override or source
IsWaitingForPlayerResponse	The resolved value, override or source
Is…OverridePresent	Whether an override is masking the source, per value
Is…OverrideOwner(object owner)	Whether this owner holds it, per value
…OverrideOwner, …OverrideOwnerKind	Who holds it and how, per value

Events

DialogueStateOverrideChanged fires when either lane's override changes, with a DialogueStateOverrideChange carrying:

Field	Holds
Member	Which value changed: ListeningToSpeaker or WaitingForPlayerResponse
Transition	Which kind of change. See Sources and Overrides
HadPreviousOverride	Whether an override was present before
PreviousValue	What it was
PreviousOwnerKind	Who held it before

One event serves both lanes, so check Member first.

Where It Reaches

Into the conversant state, which resolves to Talking, Listening or Idle and is read by the eyes and by breath. What each of those states changes is set out in Speaking and Listening.

Listening Is the Reason This Lane Exists

A character can tell it is Talking from its own audio. It cannot tell it is Listening, because nothing is playing. This lane is how it finds out, and until you wire it up a character will never resolve to Listening at all.