## 2 Three-Dimensional Information Technologies in Cultural Heritage  
In connection with the above, this Special Issue presents the results of research that applies the latest 3D information technologies to examine broadly understood cultural heritage. Eleven scientific articles have been published after a thorough and competent peer-review process. The widest group of articles [2; 3; 4; 5; 6; 7] are concerned with the 3D information technology techniques and methods that are used to protect and popularize the cultural heritage. Another group of papers [8; 9; 10; 11] examine the practical aspects of using information technology to popularize cultural heritage and detect vandalism in the form of graffiti. Article [11], on the other hand, presents the methods used to select 3D scanners. [PERSON] et al. [2] present the results of the digital restoration and documentation of the Imperial Gates from the Wooden Church of Voivodeni in Salaj County, Romania. The results of research on wooden churches from Transylvania in Romania, which are a unique and representative resource of rural cultural heritage in this region, are presented. Wooden churches are subject to natural degradation, especially as they are abandoned by their owners in favor of modern buildings. The research presented in this article combines XRF (X-ray fluorescence) and FTIR (Fourier transform infrared) spectroscopy, as well as augmented (AR) and virtual reality (VR) technologies. [PERSON] et al. compare two techniques of data acquisition and constructing 3D cultural heritage models [3]. They compare two object-scanning techniques: Structure-from-Motion (SfM) and Structured-light 3D Scanning (SLS). Their research consisted of photographing, using SfM, and scanning, using a special SLS device, the same historic object in the Afrasiyab museum in Samarkand, Uzbekistan. They describe data processing flows for both methods, and conclude that the cheaper and more widely available SfM method allows the construction of 3D models of objects of a sufficient quality to present and disseminate in media. The article by [PERSON] et al. [4] presents their research on a crested helmet from Tomb 1036 from the Casale del Fosso necropolis, Veii, Italy. In the research, the photogrammetry method was used to build a 3D mesh model of the object, as well as the X-ray fluorescence (XRF) method to analyze the helmet material's chemical composition. They visualize multiple XRF analysis results by constructing a 3D model of the helmet, which allows for a more intelligible presentation of data and helps in their interpretation. The work by [PERSON] et al. [5] is a systematic review of 3D scanning techniques for historical costumes based on articles from eight databases, covering 2879 studies. The PRISMA protocol was adopted as the methodological basis for their literature research. Their basic conclusions indicate that a very small number of articles are related to the 3D scanning of historical costumes, the most commonly used techniques are photogrammetry and laser scanning, and the basic goals of most projects are to disseminate information about historical costumes. [PERSON] et al. present an innovative method of digitally capturing of folk dances [6]. They use a motion-capture technique and installation, as well as a developed wire model of the human hand, which complements the whole-body model. The above technique captures the movement of a dancer performing the Lazgi dance, which originates from the Khorezm region in Uzbekistan. Their research is one of only a few examples of digitizing intangible cultural heritage, such as dance or folk customs. [PERSON] et al. use 3D scanning and an algorithm to highlight petroglyph patterns [7]. Their developed software analyzes 3D scans of petroglyphs in Hodjikent, Uzbekistan. They use the Structured-light 3D Scanning (SLS) method to acquire petroglyph data, and after appropriate post-processing, analyze the 3D model using an algorithm and a program developed by the authors.