打破第四道牆： 以敘事理論為基礎之個人化3D互動敘事創作系統

Abstract

互動敘事為敘事創作開啟了許多新的可能性，不論是在各種多媒體敘事創作平台上或是提供更擬真、更深刻的說故事體驗，是傳統敘事所無法提供的。透過日新月異的傳播工具，要在各種平台上創作出這類多媒體互動敘事，對於各種敘事創作者來說是一項相當大的挑戰，也引發了許多相關議題的探討：要如何開發出好用的創作工具，不但是可以降低創作技術門檻，同時也提升創造力。如何設計出一個創作模型是能夠讓故事建構者（包含原創作者、中介創作者、體驗者等本系統目標使用者）對於故事內容、結構以及像長度、複雜度、主軸、文類等故事特性有更多的控制權。\n 為了探討這議題，本研究提出一個多媒體敘事創作以及互動敘事腳本產生的框架，結合 3D 戲劇平台建立一個具有創作環境，以故事建構者設定的條件與敘事理論為基礎的故事篩選與腳本產生機制，及3D虛擬模擬環境的互動敘事系統。在創作與故事產生方面，故事建構者可以針對各種條件的篩選（像是故事主軸、長度、敘事架構、時間順序等等）由同一組故事片段產生各種敘事上的可能性。本研究設計一個演算法，有效重組既有的故事片段以產生符合作者所有條件設定的互動敘事腳本。\n 這種機制的另一個特色就是所產生的互動敘事腳本與敘事平台是獨立的，不受到特定平台的技術門檻、創作格式所侷限。為展現此腳本產生系統在各種敘事表現形式上的彈性，在本研究的系統實作中，可以同時產生故事的文字形式並在3D敘事系統 The Theater 上以即時的動畫、攝影機規劃與簡易互動呈現結果。最後，此研究設計一個質化前導實驗，以了解使用者面對具互動、動畫與個人化的敘事內容時，會有甚麼看法與反應。\n 此次研究的貢獻為設計一個建構在3D虛擬環境上的互動敘事創作的架構，並提供適當的故事腳本產生機制，讓創作者的故事片段擁有重複利用價值。此外，透過故事內容的篩選過程，我們能提供故事建構者在故事結構與內容上有高度的控制，讓產生出來的敘事腳本符合故事建構者所設定的條件、具有良好的敘事理論基礎，並即時在3D虛擬環境中以角色動畫演出。以這次建立互動敘事平台的經驗以及於使用者測試中所得到的回饋，本研究也對於敘事創作介面與輔助工具提供一些設計原則，並提出一些互動敘事系統未來可再延展的議題。

Interactive storytelling opens a world of possibilities for narrative creation on multimedia platforms, allowing a more compelling and immersive experience compared to traditional narratives. With the emergence of new storytelling technologies, the authoring of such narratives in complex virtual environments becomes an issue critical in the domain of multimedia storytelling platforms: How can we reduce the authoring effort as well as enhance creativity for interactive narratives? How can we design a flexible framework to allow creators of the story (including authors and experiencers at various stages of the interactive story) to have control over the story content and structure based on characteristics such as length, complexity, plot line, and genre?\n In order to address these issues, we propose the design of an interactive storytelling platform with models for authoring, story generating based on narrative theory and constraints set by story creators, and simulation in virtual environments. In the platform the creators of the story can specify characteristics (such as plot, length, narrative structure, time sequence, and etc.) on story fragments in order to generate variations of interactive stories. An algorithm we devise will filter and recombine story fragments from these characteristics, generating a high-level interactive script that satisfies all authorial and structural constraints.\n This mechanism provides sufficient abstraction from the technical implementation in that it is platform independent, and can be highly expressive in various forms of discourse. To implement the results of the story generation and demonstrate the abstraction from the virtual environment, we simulate the generated interactive narrative both in text form and in the 3D animation environment of The Theater. The Theater platform is complete with autonomous character animation, simple interaction methods, and automatic camera planning. Finally, we carry out a qualitative pilot study to understand how users would perceive and react to the animated, interactive, and personalized narrative content.\n Through this implementation, our contributions are to design a flexible framework for authoring interactive narratives for 3D environments, and also provide story generating tools that allow easy reuse and recombining of existing story fragments. Moreover, the filtering and selection process provides high-level control over the story content and structure, thus enforcing the authorial control as well as ensuring the generated stories have a basis in narrative theory. From the experience of implementing this platform and feedback obtained from the user experiment, we hope to suggest design principles for authoring tools and interfaces of interactive narratives.