RT Racing: Perception-Oriented Hybrid Reflection Switching for a Real-Time Racing Game

• Izequiel P. de Norões UNIFOR
• Emanuele V. Linhares UNIFOR
• Maria Andréia F. Rodrigues UNIFOR

DOI: https://doi.org/10.5753/sbgames.2026.25497

Resumo

Introduction: Real-time Ray Tracing (RT) improves reflection fidelity in digital games, but its computational cost remains challenging for interactive applications. In fast-paced racing games, motion, camera displacement, and player focus may reduce the perceptual relevance of high-precision reflections in peripheral or transient regions. Objective: This paper presents RT Racing, an Unreal Engine 5 prototype for investigating perception-oriented hybrid reflection switching in a real-time racing game. Methodology: The prototype supports four configurations: full Ray Tracing, Screen Space Reflections (SSR), a hybrid reflection mode, and a low-quality baseline. We combine spatial analysis of rendering complexity using Unreal Engine diagnostic view modes with a user evaluation involving 15 participants, who assessed visual fidelity, reflections, lighting, perceived stability, and gameplay-related aspects. Results: The hybrid mode achieved perceptual scores close to RT Full and SSR, while the low-quality baseline received consistently lower evaluations. Observations suggest that dynamic lighting, reflective surfaces, environmental diversity, and performance feedback supported engagement, whereas interface legibility, lap feedback, vehicle physics, and NPC recovery remained limitations. The results provide preliminary evidence that perception-oriented hybrid reflection strategies can help balance visual quality and rendering cost in racing games.

Palavras-chave: Ray Tracing, Screen Space Reflections, Hybrid Reflection Switching, User Perception, Perceived Performance, Real-Time Rendering, Racing Game

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