A concept of levels of detail for modeling Buddhist statues in 3D

According to CityGML, 3D models at different Levels of Details (LoDs) are defined to meet the geometric requirements of various applications. Following this principle, this paper introduces a concept of LoDs for the 3D modeling of Buddhist statues. The procedure consists of four steps: (1) inventory of applications, (2) analysis of geometric requirements in applications, (3) determination of the number of LoDs, and (4) design of geometric representations of each LoD. Based on 60 application scenarios, we proposed four LoDs for Buddhist statue modeling. LoD1 is defined as 2D symbols for geospatial analysis, LoD2 uses convex hull geometry for GIS applications, LoD3 is represented by coarse solid boundary representation of primary components for applications such as conservation and transportation, and LoD4 models detailed geometries for every small component to support various types of archeology calculations. The key feature of the proposed LoD concept is the integration of semantic information, which serves as fundamental data for interoperability in computer-aided applications. Based on the proposed LoD in this paper, a CityGML Application Domain Extension (ADE) can be developed for the 3D digital modeling of Buddhist statues or even figure sculptures more broadly. The procedure developed in this paper could be generally used to design LoDs for other types of features in context with their application needs. Although this study focuses on Buddhist statues, the proposed LoD framework is adaptable to other sculptural traditions that require semantic-aware modeling, thereby enabling broad applicability across different cultural heritage domains.