Rafael Padilla

Rafael Padilla, Kyle Webster, Austin Kim

Over the last decade, advances in GPU hardware have been driven in large part by the demands of real-time graphics, culminating in dedicated hardware ray tracing cores (RT cores). These units accelerate ray scene intersection queries directly in hardware, making physically based ray tracing algorithms increasingly practical for interactive applications. This paper compares and analyzes the performance of two ray-based rendering algorithms: forward path tracing (PT) and wavefront path tracing (WPT). GPU-based PT computes the color of each pixel by having each thread trace a single path to completion, naturally leading to a megakernel approach - while WPT maintains state buffers between specialized kernel invocations to trace path stages simultaneously. We find that WPT affords a ~16% speedup over PT in our implementation. By analyzing traces from NVIDIA Nsight Graphics, we attributed this speedup to WPT's improved cache locality compared to PT. We also find that our implementation does not achieve maximum GPU throughput across any of its units, suggesting that communication and memory latency, as well as synchronization, are the limiting factors. Finally, we address potential algorithmic improvements and future work for real-time path tracing implementation for practical applications.

Rafael Padilla, Özgür Keleş

Recent advancements in virtual reality (VR) technology have enabled the creation of immersive learning environments that provide engineering students with hands-on, interactive experiences. This paper presents a novel framework for virtual laboratory environments (VLEs) focused on embodied learning, specifically designed to teach concepts related to mechanical and materials engineering. Utilizing the principles of embodiment and congruency, these VR modules offer students the opportunity to engage physically with virtual specimens and machinery, thereby enhancing their understanding of complex topics through sensory immersion and kinesthetic interaction. Our framework employs an event-driven, directed-graph-based architecture developed with Unity 3D and C#, ensuring modularity and scalability. Students interact with the VR environment by performing tasks such as selecting and testing materials, which trigger various visual and haptic events to simulate real-world laboratory conditions. A pre-/post-test evaluation method was used to assess the educational effectiveness of these VR modules. Results demonstrated significant improvements in student comprehension and retention, with notable increases in test scores compared to traditional non-embodied VR methods. The implementation of these VLEs in a university setting highlighted their potential to democratize access to high-cost laboratory experiences, making engineering education more accessible and effective. By fostering a deeper connection between cognitive processes and physical actions, our VR framework not only enhances learning outcomes but also provides a template for future developments in VR-based education. Our study suggests that immersive VR environments can significantly improve the learning experience for engineering students.