The development of realistic virtual actors in many
applications, from user interface to computer entertainment,
creates expectations on the intelligence of these actors
including their ability to understand natural language. Based
on our research in that area over the past years, we highlight
specific technical aspects in the development of
language-enabled actors. The embodied nature of virtual
agents lead to specific syntactic constructs that are not unlike
sublanguages: these can be used to specify the parsing
component of a natural language interface. However, the
most specific aspects of interacting with virtual actors
consist in mapping the semantic content of users’ input to the
mechanisms that support agents’ behaviours. We suggest
that a generalisation of speech acts can provide principles for
this integration. Both aspects are illustrated by results
obtained during the development of research prototypes.
