遮擋問題是體積資料中可能存在無法被發現的重要隱藏特徵。這是將體積渲染
到2D 屏幕時會遇到的主要問題。過去已經提出了許多技術，例如調整傳遞函數、等值面提取等，以解決遮擋問題並幫助專家探索體積資料。然而，對於沒有多少先驗知識的非專家用戶來說，很難花數小時學習相關信息，例如如何調整傳遞函數或不透明度與體積數據之間的關係。目前給非專家用戶的現有系統仍然需要用戶理解不透明度函數。因此，我們提出了一種漸進式的挖掘交互以允許非專家用戶探索的方法，這些方法更直觀，更接近日常生活行為。我們還提供材質結構的導覽視圖，使非專家用戶能夠以最少的先驗知識開始使用體積探索系統。此外，我們通過案例研究收集多個領域的用戶反饋，以說明我們系統的可用性、實用性和適用性。

The occlusion problem is possible that there are potentially critical hidden features in the volumetric data that cannot be discovered. This is the primary problem when rendering volumes to 2D screens. Numerous techniques, such as tuning the transfer function (TF), isosurface extraction, etc., have been proposed in the past to address the occlusion problem and assist experts in exploring volumetric data. However, it is difficult for non-expert users with little prior knowledge to spend hours learning related information, such as how to tune the TF or the relation between opacity and volumetric data. Existing systems for non-expert users still need users to comprehend the opacity function. Therefore, we propose a progressive digging interaction to allow non-expert users’ exploration approach, which is intuitive and closer to daily life behavior. We also provide a navigation view of the feature structure and enable non-expert users to begin using the volume exploration system with minimum prior knowledge. In addition, we collect user feedback in several fields through case studies to illustrate our system’s usability, practicality, and applicability.

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