To display barks, the Dialogue System uses a component that implements the PixelCrushers.DialogueSystem.IBarkUI interface, such as Unity GUI Bark UI or NGUI Bark UI Component. The component can display floating text above the NPC's head, write the text to a chat window, etc., depending on the particular implementation.
The Dialogue System comes with these bark UIs built in:
In addition, you can create your own bark UI:
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