基於雙向路徑導引之強韌光傳輸模擬

Bidirectional Path Guiding for Robust Light Transport Simulation

周家宇(Chia-Yu Chou)

指導教授 ： 歐陽明

國立臺灣大學/電機資訊學院/資訊網路與多媒體研究所/碩士(2020年)

https://doi.org/10.6342/NTU202001074

摘要

本篇論文提出了一個基於實際路徑導引的雙向路徑導引演算法。實際路徑導引使用空間方向樹來儲存入射輻射並且透過疊代的方式進行訓練。我們藉由使用兩個空間方向樹分別儲存輻射以及重要性將實際路徑導引延伸到雙向路徑導引。除了前項延伸以外，我們也提出了一套稱為雙向數據紀錄的方法，用於僅在單一子路徑中記錄不同數據（輻射及重要性）。我們也將透過含有複雜光路徑的場景與其他無偏差方法進行比較。

關鍵字

光照傳輸 ； 全局光照 ； 路徑導引 ； 渲染 ； 光線追蹤

並列摘要

This thesis presents a bidirectional path guiding algorithm based on the practical path guiding (PPG) method. PPG uses a spatial-directional tree (SD-tree) to store incident radiance and trains it iteratively. We extend PPG to bidirectional path guiding by using two SD-trees that store radiance and importance respectively. Apart from the above extension, we also introduce a method called bidirectional data recording (BDR) for recording different data (radiance and importance) only in a single subpath. We also compare our results to other unbiased methods with scenes containing difficult light paths.

並列關鍵字

light transport ； global illumination ； path guiding ； rendering ； ray tracing

參考文獻

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