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Custom Playback Types

Create a custom character playback in C++ or in Blueprint by creating a class of type InworldCharacterPlayback.

C++ and Blueprint playbacks share the same events to handle inworld messages.

Events​

BeginPlay​

void BeginPlay()

Used for initialization.

EndPlay​

void EndPlay()

Used for deinitialization.

Tick​

void Tick(float DeltaTime)

Called every frame.

OnCharacterInteractionState​

void OnCharacterInteractionState(bool bInteracting)

Called when the owning InworldCharacterComponent has begun interacting with an InworldPlayerComponent.

OnCharacterPlayerTalk​

void OnCharacterPlayerTalk(const FCharacterMessagePlayerTalk& Message)

Called when the owning InworldCharacterComponent has been talked to by an InworldPlayerComponent.

OnCharacterEmotion​

void OnCharacterEmotion(EInworldCharacterEmotionalBehavior Emotion, EInworldCharacterEmotionStrength Strength)

Called when the owning InworldCharacterComponent has changed emotion states.

OnCharacterUtterance​

void OnCharacterUtterance(const FCharacterMessageUtterance& Message)

Called when the owning InworldCharacterComponent has uttered.

OnCharacterUtteranceInterrupt​

void OnCharacterUtteranceInterrupt(const FCharacterMessageUtterance& Message)

Called when the owning InworldCharacterComponent has been interrupted during an utterance.

OnCharacterSilence​

void OnCharacterSilence(const FCharacterMessageSilence& Message)

Called when the owning InworldCharacterComponent has been silenced.

OnCharacterSilenceInterrupt​

void OnCharacterSilenceInterrupt(const FCharacterMessageSilence& Message)

Called when the owning InworldCharacterComponent has been interrupted during a silence.

OnCharacterTrigger​

void OnCharacterTrigger(const FCharacterMessageTrigger& Message)

Called when the owning InworldCharacterComponent has custom trigger invoked.

OnCharacterInteractionEnd​

void OnCharacterInteractionEnd(const FCharacterMessageInteractionEnd& Message)

Called when the owning InworldCharacterComponent has completed their current interaction.

Message Queue Control​

For some playbacks, it may be desired to pause the InworldCharacter's message queue, and resume the queue once the playback has finished processing the message.

Multiple playbacks may lock the message queue at the same time. The InworldCharacter will resume message processing once all playbacks have released their lock.

void LockMessageQueue()
void UnlockMessageQueue()

Sample Custom Playback - TTS​

A common request is for characters to use a custom TTS instead of the voice audio provided by Inworld. The following shows a Blueprint example of a custom playback to replace the provided InworldCharacterPlaybackAudio using Unreal Engine's TTS.

⚠️ To follow this example, the 'TextToSpeech' plugin by Epic must be enabled for the project under Edit > Plugins.

TTS Plugin

Initialization​

To use the Unreal TTS, there is some required initialization. On Begin Play, add a default channel to the Text to Speech Engine Subsystem.

TTS On Begin Play

⚠️ If used for multiple characters, this Channel Id should be unique. 'TTS' is hard-coded here for brevity.

Playing voice​

When the owning InworldCharacterComponent has an utterance, it is desired to play audio. On Character Utterance, activate the 'TTS' channel and speak on it. To prevent the InworldCharacter's message queue from continuing until the speech is finished, use 'Lock Message Queue'.

TTS On Character Utterance

Handling Intterupts​

When the owning InworldCharacterComponent is interrupted while uttering, it is desired to stop the audio immediately. On Character utterance Interrupted, simply deactivate the 'TTS' channel.

TTS On Character Utterance Interrupt

Continuing the Queue​

Since we put a hold on the processing of the InworldCharacter's message queue in OnCharacterUtterance, it is necessary to allow it to continue once the speech is over. On Tick, try to use 'Unlock Message Queue' if the 'TTS' channel isn't being spoken on.

TTS Tick

⚠️ It's not recommended to utilize Tick. Prefer using callbacks for event completion. In this case, the Text to Speech Engine Subsystem doesn't have an event to bind to, so checking on Tick will be used for the example.