When the Storyteller is a Computer

Transcription

1 When the Storyteller is a Computer Mariët Theune University of Twente DECC workshop, 10 April 2006

2 A traditional storyteller Oral tradition, telling stories by the campfire Nowadays more media are available to tell stories This includes digital media 10 April 2006 DECC workshop Leiden 2

3 Digital Storytelling Not just using digital media to create stories but storytelling by the computer, either on its own or with varying degrees of human involvement Computer as author Human as author 10 April 2006 DECC workshop Leiden 3

4 Storytelling Computer This is just one form of digital storytelling Different forms of interactive storytelling are also possible 10 April 2006 DECC workshop Leiden 4

5 Forms of Interaction User roles: Audience (feedback, requests) Director / controller (third person) Character / player (first person) Author 10 April 2006 DECC workshop Leiden 5

6 Applications Entertainment Education Cultural heritage Group building Simulation and training Decision making 10 April 2006 DECC workshop Leiden 6

7 Papous (INESC, Portugal) Users as audience can indicate preference for functions (Propp), moods, characters, and scenes (Picture from Silva et al., AISB 04) 10 April 2006 DECC workshop Leiden 7

8 FearNot! (VICTEC EU project) Anti-bullying education Users are invisible friends giving advice 10 April 2006 DECC workshop Leiden 8

9 TEATRIX (INESC, Portugal) Children create stories by controlling the characters in a virtual environment Director agent offers guidance and makes children reflect 10 April 2006 DECC workshop Leiden 9

10 Façade (Mateas & Stern, 2005) User as player in Interactive Drama The user visits two old friends and gets caught up in their marriage crisis downloadable at 10 April 2006 DECC workshop Leiden 10

11 GEIST (ZGDV Darmstadt) Augmented reality tour of historic Heidelberg Virtual characters tell stories about the locations Adapted to available time and route taken by the user (Picture from Braun, WSCG 03) 10 April 2006 DECC workshop Leiden 11

12 MRE (USC California) Mission Rehearsal Exercise User as player (protagonist) / decision maker 10 April 2006 DECC workshop Leiden 12

13 Scenejo (Spierling et al., Germany) Story authoring tool Stories are conversations between agents 10 April 2006 DECC workshop Leiden 13

14 Intermezzo: Story vs Game Game: user always active Story: user may be more or less passive stories games Game: skills, competition Story: content / message, experience 10 April 2006 DECC workshop Leiden 14

15 Story structure More than a chronological sequence of events Sense of completeness Climax Complication, rising action Unravelling, falling action Beginning Resolution 10 April 2006 DECC workshop Leiden 15

16 Story requirements Story must be engaging Recognition and identification Conflict, tension, suspense, unexpectedness, surprise,... Good stories make the user feel ( Did it make you cry? Murray 2005) and reflect Of course, what makes a story good depends on the application. 10 April 2006 DECC workshop Leiden 16

17 The Virtual Storyteller Multi-agent system, currently still non-interactive Fabula / plot creation Levels: Fabula / plot creation Presentation - language + speech - visualisation Presentation 10 April 2006 DECC workshop Leiden 17

18 Fabula structure From: Swartjes April 2006 DECC workshop Leiden 18

19 Example fabula 10 April 2006 DECC workshop Leiden 19

20 Example output From: Slabbers 2005 Er was eens een kabouter, die Plop heette. Hij had honger en dacht dat er een appel in een huis lag. Daarom wilde hij de appel eten. Nadat kabouter Plop de appel op had gepakt, at hij hem. 10 April 2006 DECC workshop Leiden 20

21 Challenges Plot versus character Flexibility / creativity Interactivity Believable characters Authoring tools 10 April 2006 DECC workshop Leiden 21

22 Plot versus Character Character-driven stories emerge from autonomous characters actions BUT this does not necessarily lead to a wellstructured or interesting story A scripted plot provides strong structure but no character autonomy Common solution: drama manager 10 April 2006 DECC workshop Leiden 22

23 Managing the drama Balancing character autonomy / plot requirements Dealing with unexpected situations Virtual Storyteller: case-based reasoning using a story database Choosing between different options: User annotation / feedback Reinforcement learning (Mateas & Stern 2006) 10 April 2006 DECC workshop Leiden 23

24 Detailed architecture 10 April 2006 DECC workshop Leiden 24

25 Interactivity How to guide the user without breaking immersion? Virtual Storyteller: Changing the story world / influencing perceptions User interface and presentation Intuitive interfaces How to present (limited) options? How to report on user actions? 10 April 2006 DECC workshop Leiden 25

26 Believable characters Believability is not about looks but about behaviour Increased awareness of the importance of communication Both verbal and nonverbal communication (and what about user input?!) Expressing personality and emotion are important, but not the whole story 10 April 2006 DECC workshop Leiden 26

27 Storytelling prosody General speaking style: Er was eens een man die geweldig rijk was Sudden climax: Hij wilde zich omkeren en toen klonk er plotseling een harde knal Increasing climax: Stap voor stap kwam hij dichterbij. Toen hij haar dicht genoeg genaderd was, greep hij haar bij haar keel en toen bleek ze plotseling verdwenen 10 April 2006 DECC workshop Leiden 27

28 Authoring tools Authoring stories can be entertaining Easy authoring is important to create new applications However Most storytelling systems can be used only by the developer, not by naïve users 10 April 2006 DECC workshop Leiden 28

29 Conclusions Storytelling is a growing, multidisciplinary field Increasing interest in storytelling for various applications Large overlap with gaming Not so easy to achieve storiness, especially in combination with interaction Keep trying! 10 April 2006 DECC workshop Leiden 29

30 More information about the Virtual Storyteller: 10 April 2006 DECC workshop Leiden 30