Cultural Heritage Preservation Using Constructive Shape Modeling

Abstract

Issues of digital preservation of shapes and internal structures of historical cultural objects are discussed. An overview of existing approaches to digital preservation related to shape modeling is presented and corresponding problems are considered. We propose a new digital preservation paradigm based on both constructive modeling reflecting the logical structure of the objects and open standards and procedures. Constructive Solid Geometry (CSG) and Function Representation (FRep) are examined and practically applied as mathematical representationsproducing compressed yet precise data structures, thus providing inter-operability between current and future computer platforms crucial to archiving. Examples of CSG reconstruction of historical temples and FRep modeling of traditional lacquer ware are given. We examine the application of fitting of a parameterized FRep model to a cloud of data points as a step towards automation of the modeling process. Virtual venues for public access to cultural heritage objects including real time interactive simulation of cultural heritage sites over the Web are discussed and illustrated.

Digitally Interpreting Traditional Folk Crafts

“…The earlier stages of this project, namely modeling existing lacquer ware artifacts and Web presentations of the models were reported in [16,25]. In this paper we concentrate on the automation of the fabrication of traditional craft items as well as experimental modeling and manufacturing of new designs and forms.…”

“…These representations allow for creation of 3D models that are as complete as possible and represent objects' internal structures, design logic (showing how simple components are interconnected into complex structures), and history of the shape construction, as well as time-dependent aspects and other parametric dependencies. More detailed discussions of shape representations for the cultural heritage preservation can be found in the next section and in [16].…”

“…In candidate as a tool for preservation and digital fabrication of cultural heritage objects. Additional discussion on shape representations for cultural heritage preservation can be found in [16].…”

“…Different techniques of depth data generation for automatic relief carving were described in [15]: polygon-to-function conversion, pattern dependent interpolation and ray-casting 3D models; while the carving operation itself was implemented using offsetting with the offset distance modulated by the generated depth data. Another approach to the automation of the model generation is based on fitting an existing parameterized template model to a point cloud data of a scanned artifact instance [16]. This approach was extended in [17] by the automatic generation of the template construction tree using the segmented point cloud.…”

“…For certain applications a difficulty of constructive modeling is that it usually is not an automated process, taking time and requiring some skill in 3D modeling However, it can be beneficial and even critical to have a constructive model for advantages and benefits discussed earlier. Therefore, we examine in [16,17] several approaches to the modeling automation such as fitting a parameterized FRep template model to a cloud of data points, and extraction of the logical structure of the model in the form of the construction tree using genetic algorithms.…”