臺灣博碩士論文加值系統

群體運動在3D電腦動畫中是一門重要的技術，且廣泛的應用在現今的商業電影，因為群體動畫要處理大量的動作資料，如果使用動畫師手動來調整每一位個體的keyframe則是耗時費力的方法，而且還必須能夠控制整個群體的行動。本文的研究將重點集中於群體的動作控制，利用動力學來模擬可變換領導者來帶領群體的移動，並且利用MEL來架構出一個群體系統，提供圖形化介面讓動畫師使用。

該群體系統主要運作架構於以下幾點：一、利用分子系統來模擬Reynolds所提出的群體運動法則；二、利用動力學來模擬領導者與可變換領導者；三、利用分子系統及expression來模擬群體運動的小組分離。

本論文並且利用此系統實際作出3D電腦群體動畫來做驗證，並且更將其與流體結合，以用來模擬火焰、煙霧等特效的製作。

Crowd simulation is an important technique in 3D computer animation and has been applied popularly to today’s commercial films. For crowd scene, without crowd simulation solution to process the great amount of motion data, the animators would have to spend much time and effort in modifying the keyframes of each character and keeping the motion of all of the individuals as a whole. This thesis focuses on the motion control of the crowd using dynamics to simulate changeable leaders to pilot the move of the crowd. A crowd system using MEL is builded to provide the animators a GUI for crowd simulation.

This crowd system is based on: 1. using particle system to simulate Reynold’s rules of crowd simulation. 2. using dynamics to simulate leaders and changeable leaders. 3. using particle system and expressions to simulate the separation of the crowd.

This thesis also provides a verification by using the crowd system to produce some 3D crowd scenes. Furthermore, it combines the crowd system with fluid shader to simulate fire and smoke.

Keywords: Crowd Simulation, 3D Computer Animation, Crowd Leader, Motion Control.

摘 要..................................I
Abstract.................................IV
目 錄..................................VI
圖 目 錄..................................VII
表 目 錄..................................IX
第壹章 緒論...............................1
第一節 研究動機...........................1
第二節 研究目的...........................5
第貳章 文獻探討...........................6
第一節 群體動畫概述........................6
第二節 群體動畫行為法......................8
第三節 動力學製作法........................12
第四節 程序性製作法........................14
第五節 影像合成法..........................15
第六節 路徑搜索與跟隨領導者.................17
第七節 分子動畫與人工生命...................18
第八節 小結...............................20
第叁章 研究方法與架構.....................21
第一節 研究方法...........................21
第二節 研究架構與流程......................22
第三節 系統流程與架構......................23
第四節 研究範圍與限制......................24
第肆章 可變換領導者應用於群體的方法探討與實現.25
第一節 群體行為的準則與模擬.................25
第二節 可變換領導者........................30
第三節 小組分散設置........................36
第四節 群體系統介面的建立...................40
第五節 實作動畫驗證........................47
第六節 群體系統在火、煙、爆破的特效應用.......55
第伍章 結論及未來研究方向...................57
第一節 結論...............................57
第二節 未來研究方向........................59
參考文獻...................................60

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