Are we telling the same story? Balancing real and ... - ResearchGate

Figure 8 - Princess RelationDirectorAs said before, the emergence of a story with severalautonomous entities, our cast and our users should result ifthe process of acting and reacting is collaborative inessence. For example, an agent waits for another agent toperform its actions before it says its own line. This isguaranteed by the agent’s minds. However, there are otherelements in this collaborative process that are beyond theautonomous behaviours of the actors: for example, when acharacter from the cast is brought into scene. To controlsuch type of emergence we have developed a “directoragent” that controls the whole interactive process to keepthe tension values proposed previously. Although it is stillbeing implemented, this component is responsible forcollecting all the affective information produced by thecharacters, specially focusing on the emotions of the heroand the victim. Based on this information and on itsknowledge about the characters’ relations, it choosesbetween: sending a message to a character in the casttelling it to enter; sending a message to a character on thescene to leave; or not performing any action for themoment. The entrance and exit of characters will have anemotional impact on the characters’ relations, thusinfluencing the drama development. With studiesperformed with children collaborating in this storyconstruction, this type of action (managing the appearanceand disappearance of the characters) was very regularlyused. In the future we expect to augment the repertoire ofnarrative actions done by the Director.Preliminary ResultsSo far, we have shown how we approached theconstruction of a narrative drama application, where storiesemerge as a collaboration process between the users andthe agents. To achieve that, we gave the agents a rich set ofbehaviours supported by an agent architecture that allowsfor affective and social behaviour.The authoring process of I-Shadows combined elements ofacting and fairy tales (by creating heroes, victims, orvillains) and of acting itself. As the system was designed asa close collaboration between children and teachers, somegood results in terms of expression detection and emotionexpression were achieved.The following example illustrates some elements of thisprocess, with an interaction between a Princess and a Hero.Consider that the Princess loves the Hero with an intensitycorresponding to the initial value shown above. When shesees the Hero, a Show Love intention is activated by theShow Love meta goal (built into its mind).According to her emotional state, the Princess decides thatthe way of Showing Love for the hero is to offer him aCandy. This action generates a Joy emotion in the Herothat triggers a Smile.Figure 10 – Princess feels Hope of Showing LoveThe Hero’s smile is appraised by the Princess as a positiveaction. This appraisal has a positive impact on the relationwith the Hero. As a consequence, the next time theprincess intends to show love she will consider a moreintense relation with the Hero that will activate a kissintention.Figure 9- The director influencing the cast

Figure 11 – Change in the Princess’s relationConclusionsThis paper argues that, to achieve interactivity ininteractive narrative systems, we can regard the storyconstruction as a collaborative process between users andcharacters. However, for that to be possible, the charactersneed to have a role and be autonomous enough to decidewhat to do at a certain instant. In the paper, we havedescribed the construction of such type of autonomousagents using an emotional architecture based on FATiMa.This development was done in the context of the I-Shadows system, an interactive drama where the user isfree to act in the physical world by manipulating shadowpuppets.The stories created are a result of the actions of the userand the actions of autonomous characters. Furthermore,supported by theoretical groundings in interactive dramaand the role that the proposed emotional model has inachieving interactivity, we have built a Director agent thatsomehow coordinates parts of this process (based on thatemotional model).Authoring characters using FATiMa is not easy due to thelack of a real methodical authoring approach for buildingagents for interactive narrative. A character-centredapproach needs to be followed, and that is often difficult todo. Characters are acting according to their roles and havedynamic relations, and it is these roles and relations thatneed to be captured in the agents’ minds. Although theresults are so far positive, we believe however that, toreally obtain a good play, the characters need to be furtherimproved. Moreover, we expect to start evaluating thesystem with children very soon and evaluate the degree ofcollaboration achieved between the children and thesystem.Figure 12 – Hero’s emotional stateFigure 12 shows the actual hero’s emotional state afterfailing to defend a Victim. The hero was in a very positivemood because of the joy he felt when the victim expressedher love for him. Suddenly the villain hits the victim. Thehero appraised this event as a very negative action, and feltdisappointed, this appraisal generated resentment andreproach towards the action and towards his subject(Villain). As a consequence of these events, his “Like”relation will decrease towards the villain and will increasetowards the victim. And because of this he will try toprotect the victim the next time. Figure 12 shows thehero’s emotional state after defending the victim. This timethe hero succeeded in defending the victim and had apositive feeling of satisfaction.AcknowledgementsThis work is supported by the HUMAINE (Contract no.507422) project carried out with the provision of theEuropean Community in the Framework VI Programme.The authors are solely responsible for the content of thispublication. It does not represent the opinion of theEuropean Community and it is not responsible for any usethat might be made of data appearing thereinReferences[1] Riedl M., Saretto C.J,, Michael Young R. Managinginteraction between users and agents in a multi-agentstorytelling environment in Proceedings of the secondinternational joint conference on Autonomous agents andmultiagent systems, AAMAS, 2003. Pp.: 741 – 748, 2003[2] Mateas M. and Stern A.: Towards integrating plot andcharacter for interactive drama. In Socially IntelligentAgents: The Human in the Loop, AAAI symposium, 2000.

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