Computer-based Visualization of Architectural Cultural Heritage

Background European Architectural Cultural Heritage is immense, yet part of it remains invisible: churches, synagogues, and mosques that were destroyed or never built. The digital revolution now enables their revival through 3D reconstruction, an increasingly important tool in academia and digital entertainment. These “virtual 3D reconstructions” rely on figurative and textual sources to recreate lost or unbuilt artefacts. Scholars use them to study and represent the past, sparking debate on their scientific reliability. Guidelines like the London Charter and Seville Principles define standards for Computer-based Visualisation of Architectural Cultural Heritage (CVCH), but shared methods are lacking. While EU projects like Horizon 2020 address digital CH studies, none focus on vanished or unbuilt heritage. A key issue is distinguishing scientifically valid reconstructions from amateur models. This project, involving universities and private partners, aims to define guidelines for CVCH creation, documentation, and evaluation, promoting transparency and shared standards. Public awareness is crucial, as movies and games shape collective imagination. Objectives We aim to enhance digital capabilities in higher education and promote innovative learning in CH. Our goals include defining standards and a shared glossary for 3D CVCH models, creating a repository for these models, and disseminating CoVHer ideas in academia and the public. The project focuses on developing practical guidelines for studying, implementing, visualizing, and evaluating 3D models of lost or unbuilt artefacts, aligning with UNESCO’s Charter on Digital Heritage. The methodology emphasizes constructive accuracy, traceability of sources, accessibility, interoperability, and effective visualization. A key innovation is a dedicated digital repository for vanished or unbuilt heritage, distinct from existing platforms by ensuring Open Access and scientific transparency. The repository will serve scholars for research and validation, while also being accessible to the public, fostering cultural appreciation. Finally, we aim to disseminate virtual CH reconstructions standards into university curricula and the public (an important tool in this sense is the MOOC accessible to all), promoting awareness and strengthening European cultural identity. Implementation Three Learning, Teaching, and Training Activities were designed and carried out through three distinct workshops. Additionally, several educational modules on hypothetical virtual reconstructions were integrated into university courses by the main partner institutions. Five separate Multiplier Events were also organized to disseminate CoVHer’s ideas and gather feedback from the scientific community and the public. The first workshop (A1) took place in Barcelona at UAB from September 6-11, 2022, under the title: Workshop in Barcelona DIGITAL 3D HERITAGE. Exploring 3D- Modelling in Education, Documentation, and Dissemination. It involved 12 professors and professionals from the main partner institutions. Three days of joint staff training focused on using the CoVHer website and preparing Project Results 04 for the MOOC. The training was tailored to CoVHer project participants, including architects, engineers, art historians, archaeologists, restorers, and computer scientists. The second workshop (A2) was held in Mainz at Hochschule Mainz University of Applied Sciences (Germany) from September 6-13, 2023, Workshop Mainz DIGITAL 3D HERITAGE. Exploring 3D- Modelling in Education, Documentation and Dissemination. It involved 33 students and professors and focused on applying the theories and practices developed in the first three Project Results: studying standards, creating 3D models, and ensuring interoperability through the Repository platform. The third workshop (A3) took place in Porto at the Faculdade de Arquitectura Universidade do Porto (Portugal) from September 4-11, 2024, involving 44 students, professors, researchers, and professionals. Titled International Workshop on DIGITAL 3D HERITAGE. Exploring 3D- Modelling in Education, Documentation, and Dissemination, it built on the content of the first workshop but implemented a blended approach. Participants were required to complete and pass the MOOC in the month prior to the course, allowing for testing and feedback on its first draft. To disseminate findings and receive feedback from the scientific community and associated partners, five different Multiplier Events were organized throughout the project. The first Multiplier Event, the Kickoff CoVHer Event, was held in Warsaw, Poland, at Politechnika Warszawska on April 22, 2022. All main partners attended, along with international experts in virtual reconstructions, including Sander Münster (Friedrich-Schiller-Universität Jena, Germany) and Wladek Fuchs (University of Detroit Mercy, USA). The event introduced the CoVHer project to the Polish and international scientific communities and the public. The second Multiplier Event, CoVHer 2nd Event in Mainz, took place at the Institute of Architecture at Mainz University of Applied Sciences on March 3, 2023. Again, all main partners attended, along with invited international experts such as Susanne Weissman (President of Mainz University of Applied Sciences), Lisa Snyder (University of Los Angeles, UCLA), Sander Münster, and Wladek Fuchs. The event served to present the CoVHer project to the German and international scientific communities and the public. The third Multiplier Event, CoVHer 3rd Event in Mainz, took place at the Institute of Architecture at Mainz University of Applied Sciences on September 9, 2023. Again, all main partners attended, along with invited international experts such as Susanne Weissman (President of Mainz University of Applied Sciences), Keynotes by Piotr Greiner, Pictureworks Studio, Jonas Rothe, TimeRide, Marc Hernández Güell, La Tempesta. The event served to present the CoVHer project to the German and international scientific communities and the public. The fourth Multiplier Event, CoVHer 4th Event in Mainz, took place at the Faculdade de Arquitectura da Universidade do Porto (FAUP) on September 9, 2024. Again, all main partners attended, along with invited international experts such as Krzysztof Kkoszewski (Politechnika Warszawska), Eduardo Neves, Hugo Pires (FAUP), Louis Vandenabeele (VUB Architectural Engineering, Brussels, Belgium), Carlos Rebelo (University of Coimbra). The event served to present the CoVHer project to the Portuguese public and international scientific communities and the public. The fifth Multiplier Event, CoVHer 5th Event in Mainz, in Limassol – Cyprus, Hosted by EuroMed 2024 – 10th International Conference on Digital Heritage. December 4, 2024. Again, all main partners attended, along with invited international experts such as Sander Münster (Friedrich-Schiller-Universität Jena, Germany), Fabrizio Nevola and Luca Brunke from the University of Exeter, and Marinos Ioannides the director of UNESCO Chair on Digital Cultural Heritage at the Cyprus University of Technology. The event served to present the CoVHer project to the international scientific communities and the public. At each principal partner university, educational modules related to the CoVHer project were developed and implemented over the three years of the project. For example, the University of Bologna integrated didactic modules on hypothetical virtual reconstructions into the Basic Principles of Graphic Design course (4 ECTS), as part of the Lab-based Course on Architectural Drawing within the five-year single-cycle degree program in Architecture. The Bologna course engaged 100 students per academic year, totalling 300 students involved solely from the University of Bologna. Results The concrete results of the CoVHer project for Project Result 01 consist of two outputs: • A PDF book titled “Methodologies/guidelines-Cooperation processes and methodologies to outline operating standards for Generating Computer-based Visualization of Cultural Heritage (CVCH)”, which compiles the theory and practice developed during the project. • A Glossary published both as a downloadable PDF (available as a complete book) and as an interactive version on the CoVHer website under “Project Results / PR01 Methodology and Guidelines / Glossary”: https://covher.eu/. For Project Result 02, several 3D models of past architectural structures—either lost or no longer existing—were created. These 3D models were developed during the project by both researchers/professionals in the field and students involved in the initiative. Currently, the CoVHer 3D Repository contains 126 3D models entries that can be viewed and downloaded. Project Result 03 led to the creation of the first dedicated 3D repository platform entirely focused on digital hypothetical reconstructions: https://repository.covher.eu/. From this platform, as mentioned above, users can view or download the 3D models produced within the CoVHer project. For Project Result 04, specific modules related to the CoVHer project themes were introduced within university courses (during the academic years 2022/23, 2023/24, and 2024/25). Additionally, the first MOOC (Massive Open Online Course) titled “CoVHer: Computer-based Visualization of Architectural Cultural Heritage” was created, focusing on digital hypothetical reconstructions of the past. The course can be accessed at the following web page: https://book.unibo.it/. Furthermore, several academic papers have been published throughout the project, illustrating research findings and results. These can be accessed and downloaded from the official CoVHer website under the “Resources” section: https://covher.eu/. For instance, multiple articles have been published in the journal Virtual Archaeology Review, available online at: https://polipapers.upv.es/index.php/var/issue/view/1341. One such article, titled “Reconstruction of S. Margherita Project of 1685 as designed by Agostino Barelli”, presents a case study developed for Project Result 02: https://polipapers.upv.es/index.php/var/article/view/22554. The book, like the MOOC course, is organized into four sections: 1. "Get to Know Hypothetical Reconstructions" – This section covers key concepts such as “Introduction to the Idea of Computer-Assisted Reconstruction of Architectural Heritage”, “The Concept of Model”, and “Workflows, Methods, and Formats: Introduction to the Scientific Reference Model”, among others. 2. "From Broken Fragments to Reconstructed Buildings" – Primarily focused on archaeology-related concepts, including “Anastylosis”, “Geometric Completion”, and “Analogy and Template Matching”. 3. "Best Practices for 3D Modeling and Visualization" – This section explores theoretical issues and their practical applications, featuring chapters like “Best Practices for Constructing 3D Models”, “Scale, Proportions, Measures, Level of Detail”, “Semantic Segmentation and Semantic Enrichment”, and “Communicating Uncertainty”. 4. "Documenting, Sharing, and Reusing the 3D Model" – Fully dedicated to the practical aspects of using and sharing 3D models for scientific or other purposes. Chapters include “Introduction to Sharing 3D Models”, “Digital 3D Model Documentation”, and “Publication Process and Requirements for Web-Based Repositories”. Moreover, five Multiplier Events and three Workshops were organised during the project. These initiatives significantly contributed to the project's development in various ways and can be considered tangible project outcomes. First and foremost, they played a crucial role in dissemination and communication. These events facilitated the widespread promotion of the CoVHer project’s ideas within the academic community and among professionals and enthusiasts. Additionally, they provided an opportunity to gather valuable feedback from participants, which proved highly beneficial throughout the project's development. Another key outcome of the project is the creation of the official CoVHer website, which serves as a platform to collect and present some of the project's results in an interactive format. For instance, users can access the Glossary online, featuring a dedicated search engine for ease of consultation.