在本篇論文中,我們以物理學上的靜力學和動力學改進了布料動態模擬中的傳統彈力模型,並提出一套模擬程序使得模擬的過程中更有效率,使其能更有效率的達到平衡狀態且合乎物理定律.此外,對於風力及地心引力等外力的影響效果也能很真實的表現出來.
我們利用模擬過程中能依序移動點的特性,在處理碰撞的偵測和回應方面發展出一套能快速偵測布的碰撞現象並且有效的回應的系統,並且利用了階層式結構(hierarchical structure)和箱型限制區(bounding box)的特性有效的加速碰撞的偵測.於幾種碰撞偵測的模組中,我們採用了有效的加速系統.不過對於自身碰撞的偵測及變形在本篇論文中並無處理.實驗的結果顯示我們的方法的確能快速有效的產生布的動態效果.

In this thesis, we improve the traditional spring-mass model of cloth animation by dynamics and kinematics. A simulation process is proposed to make cloth animation more efficiently. Furthermore, natural phenomenon caused by external forces such as wind and gravity can be incorporated into the model to enhance the realism.
In order to handle collision detection and response, a collision process is proposed to make collision detection faster and response more efficiently by the property that is to move vertices of our model one by one. The hierarchical structure and bounding box technique in addition to ordinary pre-checking for collision detection are proposed. Three efficient speed-up methods are adopted by three collision detection stages. But we didn’t deal with self-collision detection and bending in this thesis. The experimental results show that the proposed method can create realistic cloth behavior.

Abstract ( in Chinese )
Abstract ( in English )
Table of Contents
List of Figures
Chap 1 Introduction
1.1 Overview
1.2 Introduction
Chap 2 Previous Works
2.1 Cloth Model
2.1.1 Continuous Systems
2.1.2 Finite Elements Systems
2.1.3 Particle Systems
2.2 Collision Detection
Chap 3 An Elastic Model for Efficient Elastic Cloth Animation
3.1 The Elastic Model
3.1.1 The Input Data and Data Structure
3.1.2 Applied Forces
3.2 Implementation of A Cloth Model
3.3 Static Force Distribution Within One Time Step
3.4 Dynamic Force between Successive Animation Steps
3.5 Results of The Proposed Cloth Animation System
Chap 4 Efficient Collision Avoidance Method for Cloth Animation
4.1 Simulation Process
4.2 Space Subdivision and Bounding Box
4.3 Collision Detection
4.3.1 Iterative Collision Detection
4.3.2 First Stage : Point to Triangle Collision
4.3.3 Second Stage : Edge to Triangle Collision
4.3.4 Third Stage : Triangle to Triangle Collision
4.4 Three Efficient Methods for Collision Detection
4.4.1 Projected Area Method
4.4.2 Surface Normal Difference Method
4.4.3 Surface Normal Difference at The Edge Method
4.5 Results of The Clothe Animation System
Chap 5 Experimental Results
Chap 6 Conclusions and Future Works
References

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