標題: | 用於區塊繪圖之階層式儲存方式設計 A Hierarchical Primitive List for Tile-based Rendering |
作者: | 蕭之傑 Hsiao, Chih-Chieh 鍾崇斌 Chung, Chung-Ping 資訊科學與工程研究所 |
關鍵字: | 繪圖處理器;區塊繪圖;階層式三角形列表;區塊;三角形列表;Graphics Processing Unit;Tile-based Rendering;Hierarchical Primitive List;Tile;Primitive list |
公開日期: | 2008 |
摘要: | 在現今嵌入式系統中(如:手機、個人導航裝置等)往往資源相當受
限。而具備分區塊式繪圖 (tile-based rendering)特性的繪圖處理器,在
此類應用中相當常見,其一次只處理畫面上的一個區塊,而非整個畫
面,故其處理一個區塊所需的區塊深度緩衝器(Tile Z-buffer)及區塊畫
面緩衝器(Tile frame buffer)只需與區塊大小相同即可,而非整個畫
面。故傳統繪圖處理器中時常被重覆存取之深度緩衝器及畫面緩衝
器,即可很容易的被整合至晶片中來有效降低對外部記憶體之存取。
然而傳統的非階層式三角形名單之分區塊式繪圖處理器設計中,會在
場景複雜度增高時,增大對儲存三角形列表之記憶體空間需求。在本
論文中,將修改分區塊式繪圖處理器中記錄區塊中所屬三角形的動作
(tile binning),使其能依據三角形不同邊界方框之大小、形狀及位置
決定存放在何種階層的三角形列表中,能使用較少之三角形名單來記
錄。並提出一個整合式的判斷方法,同時可以整合多種不同階層,且
不論畫面中有何種三角形之邊界方框,都能以固定的判斷次數來選定
三角形該被放在哪一個階層中。而此判斷方法也能很輕易以簡單的硬體來實現,進而減少其判斷所需的時間。透過這些修改,讓此種繪圖
處理器能在畫面複雜度不斷增高時,也能針對不同具有不同大小、形
狀及位置的三角形之邊界方框做最有效的判斷,進而減少整體儲存三
角形名單所需之空間。 Tile-based rendering has been widely used in resource-limited graphic processing environments, e.g., for hand-held devices. Since large primitives may cover a significant number of tiles, they need to be recorded in the primitive lists of all related tiles. We propose a hierarchical primitive lists structure, which also copes with misaligned and non-square primitive problems, to minimize the primitive recording. Intended advantages include: reduced storage pressure, list building time, primitive retrieval counts for subsequent rendering, and primitive data accesses from external memory during rendering, and possibly enhanced data locality/resource utilization if layer-based rendering is exploited. Based on this structure, we propose a primitive-hierarchy fitting (hardware) algorithm which, for a given primitive of any size and shape, determines a best way of storing it in the structure. Experimental results on Doom3 and Quake4 show a 73% storage reduction using only square hierarchies or 78% with our full capability, compared with flat tile-based lists. |
URI: | http://140.113.39.130/cdrfb3/record/nctu/#GT079655607 http://hdl.handle.net/11536/43413 |
顯示於類別: | 畢業論文 |