The most important component of photorealism in Computer Graphics is given by a physically correct approximation of the light transport. Besides the direct illumination from light sources, there is an indirect illumination, produced by the reflections of the light rays on other surfaces of the scene. In Computer Graphics, the process of computing the illumination of a surface by considering both the direct and the indirect illumination is widely known as global illumination. This paper describes several classes of real-time global illumination techniques used in current game engines together with our own implementations of these approaches. All implementations were made in our own framework, specially designed with a multi-pass rendering architecture that allows fast implementation of rendering techniques and the reuse of functionalities. We analyze these classes based on the following criteria: the visual results produced by the indirect diffuse lighting, the ability to produce glossy reflections, shadows, ambient occlusion, subsurface scattering, translucency and volumetric lighting as well as the ability to simulate area lights. We present the quantitative results of our implementations, obtained with the same external parameters for all techniques, thanks to the unified implementations in the same framework. An important observation is that our analysis is focused on the techniques that are based on the rasterization pipeline, thus, the comparison does not include the techniques designed entirely for the ray-tracing pipeline.

Ophiophobia is defined as a pathological state of fear and unease caused by snakes. Taking into consideration the technological advancements made in the last few years, as well as the studies that have proven the efficiency of using virtual reality exposure therapy on patients who suffer from different types of phobias, we set out to develop a 3D environment that would come to the aid of those who suffer from ophiophobia. Therefore, we have created Ophiophobia3D, a game with 2 scenarios, where the player has to collect coins while avoiding or killing snakes that crawl and try to bite. The testing phase of the game was performed with the help of 9 participants who had low and medium levels of ophiophobia. At the end of a testing experiment, we noticed a drop in the fear level of those who explored the 3D environment.

Background: Immersive virtual reality (VR) has emerged as a promising tool to enhance neuroplasticity, motivation, and engagement during post-stroke motor rehabilitation. However, evidence on its feasibility and data-driven integration into clinical practice remains limited. Objective: This pilot study aimed to evaluate the feasibility, usability, and short-term motor outcomes of an immersive VR-assisted rehabilitation program using the Travee-VR system. Methods: Fourteen adults with post-stroke upper-limb paresis completed a 10-day hybrid rehabilitation program combining conventional therapy with immersive VR sessions. Feasibility and tolerability were assessed through adherence, adverse events, the System Usability Scale (SUS), and the Simulator Sickness Questionnaire (SSQ). Motor outcomes included active and passive range of motion (AROM, PROM) and a derived GAP index (PROM–AROM). Correlations between clinical changes and in-game performance metrics were explored to identify potential digital performance metrics of recovery. Results: All participants completed the program without adverse events. Usability was rated as high (mean SUS = 79 ± 11.3), and cybersickness remained mild (SSQ < 40). Significant improvements were observed in shoulder abduction (+7.3°, p < 0.01) and elbow flexion (+5.8°, p < 0.05), with moderate-to-large effect sizes. Performance gains in the Fire and Fruits games correlated with clinical improvement in shoulder AROM (ρ = 0.45, p = 0.041). Cluster analysis identified distinct responder profiles, reflecting individual variability in neuroplastic adaptation. Conclusions: The Travee-VR system proved feasible, well tolerated, and associated with measurable short-term improvements in upper-limb function. By linking clinical outcomes with real-time kinematic data, this study supports the role of immersive, feedback-driven VR as a catalyst for data-informed neuroplastic recovery. These results lay the groundwork for adaptive, clinic-to-home rehabilitation models integrating clinical and exploratory digital performance metrics.

Background: Stroke is the third leading cause of disability. Virtual reality (VR) has shown promising results in post-stroke rehabilitation. The VR TRAVEE system was designed for the neuromotor rehabilitation of the upper limb after a stroke and offers the ability to track limb movements by providing auditory feedback and visual augmentation. The World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0), aligned with the International Classification of Functioning, Disability, and Health (ICF) principles, is a valid tool for measuring disability regardless of its cause. This study aimed to investigate the feasibility of the VR TRAVEE system in upper limb rehabilitation for stroke patients. Methods: A total of 14 stroke patients with residual hemiparesis were enrolled in the study. They underwent a 10-day program combining conventional therapy (CnvT) with VR rehabilitation. At baseline (T0), the upper limb was assessed using the Modified Ashworth Scale (MAS), active range of motion (AROM), and the Numeric Rating Scale (NRS) for pain. These assessments were repeated after the 10-day rehabilitation program (T1). Additionally, disability was measured using WHODAS 2.0 at T0 and again 30 days after completing the program. Results: Significant improvements were observed in AROM and MAS scores for the shoulder, elbow, wrist, and metacarpophalangeal joints, as well as in the reduction in shoulder pain (p ˂ 0.001). WHODAS scores decreased across all six domains, with a statistically significant improvement in the Cognition domain (p = 0.011). Conclusions: Combining CnvT with VR as a rehabilitation approach enhances motor function in the upper limb. This method has the potential to reduce disability scores and promote neuroplasticity.

Virtual reality and augmented reality technologies have experienced a significant increase in popularity due to their potential to deliver a highly immersive user experience. However, there are still substantial difficulties in creating augmented environments with different purposes that can precisely localize users. In this context, TeachAR is an augmented reality solution designed to provide students with an interactive learning experience through an augmented reality quest system. The system comprises a desktop application and a mobile application, designed for three distinct user roles: building administrators, teachers, and students. Administrators use the desktop application to upload the building’s architectural plans, create a 3D replica of it, and define a navigation graph. Then, using the mobile application, the correspondence between the real building and its replica is created. Teachers employ a simple desktop user interface to design interactive quests. Students interact with the system through the mobile application in three different use cases: free exploration of the building, guided navigation to reach a destination, and individual or collaborative quests proposed by teachers. This paper provides a brief overview of the system’s main functionalities, implementation details, and evaluation of its technical capabilities. The pilot testing is also described in this paper, revealing the potential of using the TeachAR system in schools in the educational process.

Photorealism has become a growing requirement for real-time graphics applications. Among the components needed to obtain photorealism, one of the most important is the simulation of the light transport, the result of which is called global illumination. With the growing interest in the research in this field, the need to develop a learning approach for the methods that produce real-time global illumination and a technological basis have become important topics. In this paper, we present a framework for the rapid development and testing of such methods. The framework itself does not contain their implementations, but contains a set of components that underlie them. It has been developed with a multi-pass architecture that allows the reuse of pass implementations in several technique pipelines. Moreover, this framework can be used in the process of learning real-time global illumination methods thanks to an editor with graphical user interface (GUI) that offers a rich amount of information and a set of such methods, created in the framework for demonstration purposes. We evaluated the proposed framework in two ways. First, through a comparative analysis with other frameworks, which have been created or at least can be used for educational purposes and the rapid implementation of real-time global illumination techniques. The second evaluation was made for the applicability of the framework in learning by using it as software support in the process of testing global illumination knowledge on eight participants with background in computer graphics.