March 18, 2008

EP 8.6: Learning from Façade

by Noah Wardrip-Fruin · , 6:47 am

The surface experience produced by the Façade’s processes and data is shaped by a series of choices that have clear impacts in terms of the Eliza and Tale-Spin effects. The results are instructive.

Speaking to Façade

As with Eliza/Doctor, the freeform textual interaction of Façade invites play. Unlike Eliza/Doctor, the Façade system actually models aspects of the current context and ongoing conversation, so there’s more potential reward for this play. Façade’s audience members may interact in their own styles, whether to influence Trip and Grace, to express a particular idea of the player character’s identity, or to find the edges of the system.

The player aims of individual expression and system edge-finding, which sometimes overlap, can produce particularly memorable Façade transcripts. For example, one person posting on the Idle Thumbs forums decided to play in an unusual way: taking appropriate physical actions (sitting on the couch, answering the phone) but only saying one thing:

(GONZALO picks up the phone.)
PHONE Hello? Hello?
TRIP Gonzalo, no! Don’t do that.
GONZALO Brains!!
PHONE Who is this? Travis, is that you? This is your mother.
TRIP Uhh, that’s my mother, I can hear her loud voice.
GONZALO Brains!!!!!!
PHONE I don’t recognize your voice…
PHONE I – I think I have the wrong number… ** click **
(GONZALO puts down the phone.)
(Mailman, 2005)

As the poster concludes, “Playing as a zombie is fun.” Other players on the same forum share transcripts in which they play someone who has just been shot, an alien seeking tissue samples, Darth Vader (who screams “Noooooooooooo!” after being ejected from the apartment), and Grace’s secret lover. Of course, there are also many transcripts featuring player characters somewhat closer to Façade’s expectations, but those that push the system are particularly revealing in terms of the Eliza effect. For example, the aspect of Façade that makes the zombie transcript funny is also a clear example of how Eliza effect breakdowns reveal something of the shape of the underlying system. In this case, one sees the way Façade’s drama continues executing its beat goals, for the most part, even in the absence of intelligible player behavior.

In using a free-form natural language interface, Façade makes a certain tradeoff. Players are invited to perform more richly than in many digital fictions, which often limit interaction to the selection between a set of discrete choices (with everything else producing an error message).10 On the other hand, the actions of the Façade system actually reduce each player utterance to one of a set of discrete discourse acts — and not always successfully. This creates a serious mismatch. Personally, every time that I have played Façade in a manner I considered “according to expectations” a statement I thought of as perfectly normal produced a reaction so unexpected that I found myself thinking about the shape of the underlying system.

In fact, Façade’s authors estimate that natural language understanding failure takes place about 30% of the time. As a player, my subjective feeling is that failures are less frequent, but this is due to the clever ways that Façade deflects and recovers in many circumstances. And, as Mateas and Stern write, “This tradeoff was intentional, since we wanted to better understand the new pleasures that natural language can offer when it succeeds” (2007, 206). One can see, here, that natural-language interaction offers powerful potential to the audience — but also, by digital media authors, must be regarded as an area of active research (rather than a mature technology). It also points to other research areas, such as interfaces that might allow for players to directly express Façade’s discourse acts, removing unreliable natural language understanding from the equation.11

Hearing from Façade

Interestingly, Façade also presents a similar tradeoff in the area of the Tale-Spin effect. However, this is one in which it follows the model of many contemporary games, rather than departing from it. This is the choice to use voice acting, so that Grace and Trip’s statements are performed by playing a sequence of pre-recorded sound files to which their animations are synchronized.

Just as free-form textual input allows players to be expressive, the human expression embodied in Façade’s strong voice acting is part of what makes the experience so effective. The nuances of line performance make things by turns funnier and more uncomfortable — and, overall, more engaging. On the other hand, Façade also required significant authoring effort to appropriately funnel a vast number of possible system states into a much smaller number of possible pre-recorded utterances.

If the system had used plain text as output, many more system states could have been experienced meaningfully on the work’s surface. This would have been true for two reasons. First, the mixing of pre-written segments could have been more fine grained. Façade already sounds strange when it mixes recordings of the player character’s name into lines that were specially recorded for the purpose, and going further in this direction would have greatly reduced what the experience gains from its voice acting. Second, plain text output would have opened the door to another interesting research area: the construction of systems like the “literary augmented grammars” of Brutus. These have the potential to adjust the nuance of text, by applying hand-authored rules, depending on the current system state. However, for performance-oriented systems (such as Façade and many modern computer games) this, too, is best regarded as an area of research. Though speech generation systems are rapidly improving, for many purposes voice acting will remain the more powerful approach. However, for systems such as massively-multiplayer online games, in which most non-player character dialogue takes place through text, such research could have immediate application.

Agency in Façade

Finally, there is also an element of Façade that communicates clearly to players and, when natural language understanding succeeds, operates much as they expect. This is the combination of drama management, beat goals, joint behaviors, handlers, and mix-ins — what I have called Façade’s “script.” This combination creates a performed story that progresses in a way the audience understands, during which players can direct conversation toward a range of topics, and which can take a variety of shapes that culminate in an appropriate ending.

This experience is not that of the SimCity effect, because the nature of Façade as a system is not in the foreground. Rather, as Mateas and Stern point out, it is an example of an experience in interactive media commonly termed “agency” or “intention.” Façade’s authors point to Janet Murray’s formulation of the concept, which has been particularly influential in academic circles: “Agency is the satisfying power to take meaningful action and see the results of our decisions and choices” (1997, 126). In the field of game design the idea is often associated with Doug Church, who writes of “allowing and encouraging players to do things intentionally” — understanding the game world well enough to make and execute a plan of action, then seeing a clear reaction from the game world (1999). However, it is also worth noting that a version of this concept can be seen from the earliest full-length writing on digital fictions of which I am aware: the PhD dissertation of Mary Ann Buckles. She describes this in relation to the psychological concept of “effectance” as “the desire for competence and feeling effective in dealing with the surrounding environment” (1985, 37). She discusses how the world of the early interactive fiction game Adventure works to build this experience in its audience.

The SimCity effect is one way to build the experience of agency. Façade’s script demonstrates another. Mateas argues that, in general, “A player will experience agency when there is a balance between the material and formal constraints” (2004, 125). The formal constraints are present in the shape of the fictional world, which motivate some actions and not others. The material constraints, on the other hand, are the resources available for action. Many contemporary games, for children and adults, create a sense of agency by presenting a fictional world in which one would want to move across space (e.g., to rescue a princess, to find necessary information) and fight enemies (e.g., who are mean animals, who are zombies/aliens/robots/Nazis) and providing exactly the tools necessary (well-developed mechanics for spatial movement and combat).

Given this, achieving agency is relatively well understood for game worlds with simple fictional worlds and simple available actions, because it is easy for players to understand and act within the bounds of the system.12 The SimCity effect describes a related route to agency, for more complex systems. What Façade provides, instead — in its script — is an example of a route to agency that functions with less necessity for player understanding of the system. Rather than needing to replace the audience’s initial Eliza effect notion of drama with one closer to the model of the system, players who avoid natural language understanding errors can experience agency in Façade’s world while continuing to operate largely based on mental models drawn from theater, media, and human interaction.13 We might say that this is the true dream of interactive drama.

Unfortunately, this also means that the dream remains somewhat elusive. The Façade approach, while powerful, suffers from unavoidable errors in natural language understanding. An alternative, such as players directly expressing discourse acts (rather than typing arbitrary text) would require teaching the audience to understand the system, reintroducing the importance of the SimCity effect.

Beyond Façade

In addition to research in natural language understanding and text generation, Façade also points to further work in a number of other areas. For example, in developing the approach embodied in Façade’s script, and the large amount of material necessary to support it, Stern and Mateas also developed a set of code templates that they re-used repeatedly. As they have speculated, the design elements formalized in these templates could become the primitives in higher-level authoring languages for digital fictions, or even in graphical or AI-assisted authoring tools.

In the meantime, Façade has demonstrated the power of the ideas formulated in its script — which should, in time, find their way into other digital media projects. Further, as authors adopt the techniques pioneered by Façade, their strengths and limitations will become yet more apparent. New research will explore new possibilities. As this happens, hopefully, mainstream gaming will abandon the dialogue tree, thereby increasing the potential richness of existing genres and opening the possibilities for new ones.

Further, while these relatively well-developed techniques — the cumulative result of more than a decade of technology and design research — may be adopted by mainstream digital media, researchers are likely to turn to the next challenge. Experiences like Façade will remain limited by the sheer amount of material that must be authored. Future research is likely to consider not only how to produce a wider variety of sentences based on authored rules (as in literary augmented grammars) but also how to automatically assemble structures more akin to Façade’s JDBs, or even Façade’s larger beats, as the current situation dictates. Until this succeeds, Façade -like experiences will require large amounts of authoring for every minute of dramatic experience.

More generally, Façade provides an important example of how authors can engage the history of AI. It adopts powerful tools that grow from an AI legacy. At the same time, it disposes of limiting concepts that are the baggage of that legacy — especially the insistence on seeing characters as “autonomous agents” who sense and react to each other, rather than as coordinated performers. From this perspective, for those willing to do the conceptual work, the history of AI provides an exciting source of future directions.

Finally, Façade manages to create an emotionally engaging, if often uncomfortable, interactive experience about the relationships between people. It manages this not simply through the operations of its script and characters, but also because it is designed to capitalize on the power of fiction’s most powerful tool: language. In this it provides a stark contrast to the history from which it flows, from Tale-Spin to the Woggles. But in this way it connects to another, parallel history — considered in the next chapter.


10Many make the small selection of available actions visible on the work’s surface. However, some, like text-based interactive fictions, make the search for available actions part of the experience.

11This is something that Steven Dow and Blair MacIntyre have explored in creating the “wizard” interface for their augmented reality version of Façade.

12Though design failures happen commonly, as when actions that can be used in one context cannot be used in another, for reasons unexplained by the fictional world, reducing the player’s ability to formulate and execute intentions.

13Though playing Façade also requires some basic 3D navigation literacy.