The concept of multimodal imaging, or multimodality imaging, is not new. In medicine it has been used for decades in relation with the integration of two or more distinct imaging methods to capture different types of information for the same subject. Today, multimodal imaging is pivotal in all areas of research like neuroscience, environment or military and security applications. In heritage science, in conservation and restoration projects a complete characterization of a cultural heritage asset is necessary to understand the current state of conservation and to be able to propose a correct conservation policy. This involves a multidisciplinary and multi-temporal approach ranging from material characterization to structural analysis.
3D digitization
A 3D model is a term used for a digital format that embodies multiple elements that can be interpreted and rendered in a 3D virtual environment. It is often confused with a 3D mesh model. A 3D model can contain multiple meshes, lights, materials and even animation data. A 3D mesh model refers to the geometric structure of a specific object and is composed of vertices (points in 3D space), edges (segments that connects the vertices) and polygons (or faces, formed by the edges). A 3D model can also be reduced to a single 3D mesh but can also represent an entire scene with multiple objects. The file formats for this 3D data are the same in either case. The proposed concept is based on this aspect, as the digitized buildings are going to be split in multiple sub-objects but stored on disk as a singular 3D model.
A 3D model is a term used for a digital format that embodies multiple elements that can be interpreted and rendered in a 3D virtual environment. It is often confused with a 3D mesh model. A 3D model can contain multiple meshes, lights, materials and even animation data. A 3D mesh model refers to the geometric structure of a specific object and is composed of vertices (points in 3D space), edges (segments that connects the vertices) and polygons (or faces, formed by the edges). A 3D model can also be reduced to a single 3D mesh but can also represent an entire scene with multiple objects. The file formats for this 3D data are the same in either case. The proposed concept is based on this aspect, as the digitized buildings are going to be split in multiple sub-objects but stored on disk as a singular 3D model.
Online repository
The database structure was created using migrations and seeds from CodeIgniter4 MVC framework, so that it can be re-built and replicated for any other DBMS. The chosen database system for this project was MySQL, a popular DBMS for web applica-tions due to its ease of use, scalability, and reliability. The MVC framework, however, makes this web application versatile in regards with the database system used due to its Query Builder class. The main feature of this class is that the query syntax is generated by each database adapter allowing safer queries (data retrieval, insert and update) with minimal scripting. Data input, display and update actions, all benefit from the MVC architecture. In this pattern, the Model represents the data and database interactions. The Model can represent a database table or a query for data input or update. The Controller receives feedback from the user with new data to be inserted or what to be displayed. In the first case the data sent by the user is sent to the Model to be insert in the database. In the second case the data requested by the user is retrieved from the Model and sent to the View to be displayed.
Custom 3D viewer
The main feature of this web application is the 3D custom viewer, which provides an immersive and interactive experience for users. This viewer is a defined area within the user interface where all 3D and imaging information is displayed. Users can engage with the 3D scene through a range of intuitive controls, enabling actions such as rota-tion, panning, and zooming to examine the 3D model from different angles. Addition-ally, users can select which imaging data is displayed on specific parts of the 3D model. This interactive and dynamic environment is achieved with the Three.js library, which is compatible with both WebGL 1.0 and WebGL 2.0.One of the key advantages of this 3D viewer is its cross-platform compatibility. It seamlessly runs on a variety of devices, including PCs, Macs, iOS, and Android devices, and it is fully accessible through mainstream web browsers. This versatility ensures that users can access and interact with 3D models and imaging data from virtually any-where.The 3D environment created with Three.js is based on the principles of the PBR (Physically Based Rendering) workflow. This means that materials and lighting in the scene are designed to mimic real-world physical properties, resulting in a high level of visual realism and accuracy. This not only enhances the visual quality of the 3D models but also provides a more lifelike representation of the imaging data.