照明設計在遊戲、動畫以及室內設計等領域都扮演著重要的角色，但目前的照明設計系統僅能透過反覆調整每一盞光的各項參數以獲得理想的照明效果，這種流程即使是有經驗的設計師也可能覺得耗費時間且不夠直覺。

在這篇論文中，我們開發一個結合虛擬實境的照明設計系統，其中我們設計三種照明設計介面：直接、間接與逆向介面，我們也提出一個以疊代法計算逆向照明問題 (inverse lighting problem) 的方法。我們的照明設計系統可以讓使用者以更具沉浸感、直覺且有效率的方式進行照明設計。

Lighting design is a crucial process in video games, animation, interior design, and some other fields. Current lighting design systems support only direct lighting paradigm which requires fine-tuning each light's parameters to achieve a global lighting effect.

In this study, we developed an integrated lighting design system which comprises direct, indirect, and inverse paradigms in VR environment. We also propose an iterative method to solve inverse lighting problem in a low time cost. The system provides designers with an immersive, intuitive, and effective way of lighting design.

Contents
摘要 i
Abstract ii
Acknowledgements iii
Contents iv
ListofFigures vi
ListofTables viii
Chapter 1 Introduction 1
Chapter 2 RelatedWorks 3
2.1 IndirectLightingDesignParadigm 3
2.2 InverseLightingDesignParadigm 4
Chapter 3 ProposedMethod 6
3.1 CommonInterface 6
3.2 DirectParadigm 7
3.3 IndirectParadigm 9
3.4 InverseParadigm 12
3.4.1 PaintingSystem 12
3.4.2 InverseLightingProblem 14
3.4.3 IterativeLeastSquaresApproximation(ILSA) 14
3.4.4 SolveExistingLights 16
3.4.5 AddNewLights 17
3.4.6 Summary 20
Chapter 4 ResultsandDiscussions 21
4.1 InverseParadigmEvaluationwithGroundTruth 22
4.2 InverseParadigmEvaluationwithPaintedLightingGoals 24
4.3 UserStudy 26
4.3.1 Participants 27
4.3.2 ResultsofQuestionnaire 27
4.4 Limitations 29
Chapter 5 Conclusion 30
Reference 31

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