Curtis Onuczko

Interactive story authoring: A viable form of creative expression for the classroom

The unprecedented growth in numbers of children playing computer games has stimulated discussion and research regarding what, if any, educational value these games have for teaching and learning. The research on this topic has primarily focused on children as players of computer games rather than builders/constructors of computer games. Recently, several game companies, such as BioWare Corp. and Bethesda Softworks, have released game story creation tools to the public, along with their games. However, a major obstacle to using these commercial tools is the level of programming experience required to create interactive game stories. In this paper, we demonstrate that a commercial game story construction tool, BioWare Corp.s Aurora Toolset, can be augmented by our new tool, ScriptEase, to enable students in two grade ten English classes to successfully construct interactive game stories. We present evidence that describes the relationship between interactive story authoring and traditional story authoring, along with a series of factors that can potentially affect success at these activities: gender, creativity, intellectual ability, previous experiences with programming, time playing computer games, and time spent online. Results indicate that students can successfully construct sophisticated interactive stories with very little training. The results also show no gender differences in the quality of these interactive stories, regardless of programming experience or the amount of time per week playing computer games or participating in general online activities, although a subset of female students did show a slightly higher level of performance on interactive story authoring. In the educational context of this study, we show that ScriptEase provides an easy-to-use tool for interactive story authoring in a constructionist learning environment.

ScriptEase: A generative/adaptive programming paradigm for game scripting

The traditional approach to implementing interactions between a player character (PC) and objects in computer games is to write scripts in a procedural scripting language. These scripts are usually so complex that they must be written by a computer programmer rather than by the author of the game story. This interruption in the game story authoring process has two distinct disadvantages: it increases the cost of game production and it introduces a disconnect between the authors intentions and the interactions produced from the programmers written scripts. We introduce a mechanism to solve these problems. We show that game authors (non-programmers) can generate the necessary scripts for implementing meaningful interactions between the PC and game objects using a three-step process. In the first step, the author uses a generative pattern (concept) to create a high-level description of a commonly occurring game scenario. In the second step, the author uses a standard set of adaptation operations to customize the high-level description to the particular circumstances of the story that is being told. In the third step, the author presses a button that automatically generates scripting code from the adapted pattern. We describe the results of three studies in which a combined total of 56 game story authors used this three-step process to construct Neverwinter Nights game stories, using a tool called ScriptEase. We believe that this generative/adaptive process is the key to future game story scripting. More generally, this article advocates the development of adaptive programming as an alternative to current constructive programming techniques, as well as the application of adaptive programming in many domains.

Evaluating pattern catalogs: the computer games experience

Patterns and pattern catalogs (pattern languages) have been proposed as a mechanism for re-use. Traditionally, patterns have been used to foster design re-use, and generative design patterns have been used to achieve both design and code re-use. In theory, a pattern catalog could be created and used to provide re-usable patterns within a project and across a group of related projects. This idea raises a natural question. How can we measure the effectiveness of a pattern catalog or compare the effectiveness of different pattern catalogs? In this paper, we define four metrics that can be used to measure the effectiveness of pattern catalogs. We illustrate these metrics by applying them to a case study that uses a pattern catalog of generative design patterns to generate scripting code for computer games. The metrics are general enough to assess any pattern catalog, independent of application domain or whether the patterns are generative or descriptive.

Lookahead in smodels compared to local consistencies in CSP

In answer set programming systems like Smodels and some SAT solvers, constraint propagation is carried out by a mechanism called lookahead. The question arises as what is the pruning power of lookahead, and how such pruning power fares in comparison with the consistency techniques in solving CSPs. In this paper, we study the pruning power of lookahead by relating it to local consistencies under two different encodings from CSPs to answer set programs. This leads to an understanding of how the search space is pruned in an answer set solver with lookahead for solving CSPs. On the other hand, lookahead as a general constraint propagation mechanism provides a uniform algorithm for enforcing a variety of local consistencies. We also study the impact on the search efficiency under these encodings.

Generating ambient behaviors in computer role-playing games

Many computer games use custom scripts to control the ambient behaviors of non-player characters (NPCs). Therefore, a story writer must write fragments of computer code for the hundreds or thousands of NPCs in the game world. The challenge is to create entertaining and non-repetitive behaviors for the NPCs without investing substantial programming effort to write custom non-trivial scripts for each NPC. Current computer games have simplistic ambient behaviors for NPCs; it is rare for NPCs to interact with each other. In this paper, we describe how generative behavior patterns can be used to quickly and reliably generate ambient behavior scripts that are believable, entertaining and non-repetitive, even for the more difficult case of interacting NPCs. We demonstrate this approach using BioWares Neverwinter Nights game.

A demonstration of the scriptease approach to ambient and perceptive NPC behaviors in computer role-playing games

Writing manual code to script the behaviors of thousands of non-player characters in a computer role-playing game adventure has a tremendous negative impact on the quality of games and their entertainment level. Many games use shared custom scripts for background characters that produce repetitive and predictable behaviors. Game designers often need help from programmers when designing a game story and this can lead to lost productivity and a distorted design vision. ScriptEase is a tool that enables game designers to use ambient and perceptive patterns to specify complex, non-repetitive entertaining behaviors for interactive characters, without writing code. This demonstration illustrates how entertaining ambient and perceptive behaviors can be easily and reliably inserted into BioWare Corp.s Neverwinter Nights game stories.