臺灣博碩士論文加值系統

在即時互動的三維場景中呈現陰影效果是電腦繪圖學中非常重要的一項應用, 好的即時陰影效果可以讓場景呈現更加逼真生動, 但是此技術經過二十多年的研究依然有許多值得探討的空間, 我們基於陰影邊緣圖(Shadow Silhouette Maps)的技術, 修改其核心演算法, 提出了進階陰影邊緣圖(Advanced Shadow Silhouette Maps), 使之可以儲存邊緣的屬性, 包含了邊緣線段的斜率以及邊緣的明暗面資訊等, 以及利用搜尋填色像素周圍的其他邊緣資訊來連線, 使用所得到的邊緣線段來對像素作區域上的分隔, 最後利用陰影圖(Shadow Map)及區域屬性來判斷陰影的數值, 來達到利用最少的空間, 而取得最多的資訊. 我們所提出的方法可以有效提昇陰影邊緣區域的品質來讓畫面更生動逼真.

Chapter 1 Introduction 1
Chapter 2 Related Work 3
Chapter 3 Shadow Silhouette Map 9
3.1 Build Edge Buffer 9
3.2 Render Classic Shadow Map 10
3.3 Render Silhouette Map 11
3.4 Render Scene 12
Chapter 4 Approach of Advanced Shadow Silhouette Maps 15
4.1 Render Advanced Silhouette Map 16
4.2 Connect Edges 16
4.3 Test Shadow Value 23
Chapter 5 Results and Discussion 27
Chapter 6 Conclusions and Future Work 37
Bibliography 39
Appendix 43

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