## 4 Results
### Performance Analysis: Resolution vs. Frame Rate
#### 4.1.4 Summary and Discussion  
The performance and functional evaluation revealed several key findings that provide important insights into the comparative strengths of both cloth simulation systems. The Unity Cloth system demonstrated consistent performance across all resolution ranges, maintaining a stable 72 FPS throughout all tested configurations. This remarkable performance consistency can be attributed to Unity's highly optimized internal algorithms and extensive performance tuning developed over many years. The ability to maintain performance without degradation even at high resolutions (128 \(\times\) 128) represents Unity Cloth's most significant advantage. Additionally, the system offers excellent development convenience through Unity Editor's intuitive GUI, enabling developers to implement cloth simulation without complex programming requirements. The relatively low GPU memory usage also contributes to efficient resource management, making it particularly suitable for resource-constrained environments. In contrast, the proposed GPU-PBD system showed equivalent performance to Unity Cloth up to 32 \(\times\) 32 resolution, but experienced performance degradation at higher resolutions. However, the true value of the GPU-PBD system lies in its functional capabilities. Advanced features specifically designed for XR environments--including double-sided cloth simulation, real-time hand mesh collision handling, and interaction with real-world environments through RoomMesh--represent unique characteristics not supported by Unity Cloth. Particularly noteworthy is the system's ability to generate more realistic and rich cloth folding and deformation at higher resolutions, demonstrating superior visual quality. From a practical perspective in Meta Quest 3 environments, the 32 \(\times\) 32 resolution provides an optimal balance between visual realism and real-time performance for both systems. The experimental resolution was limited to 128 \(\times\) 128 because this represents a practical upper bound for real-time cloth simulation in standalone XR devices such as Meta Quest 3. At this resolution, the vertex count reaches 16,384, and the computational load--including constraint projection and collision handling--significantly increases. Beyond this threshold, frame rates drop below acceptable levels for real-time interaction (15 FPS), compromising the XR experience. Therefore, 128 \(\times\) 128 was selected as the maximum resolution to balance visual realism, computational stability, and real-time responsiveness. For projects requiring basic cloth simulation where high performance and development efficiency are prioritized, Unity Cloth represents the more suitable choice. Conversely, when natural interaction between users' hands and real environments in Mixed Reality \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Feature** & **Unity Cloth** & \
\begin{tabular}{c} **GPU-PBD** \\ **(Single-Sided)** \\ \end{tabular} &
\begin{tabular}{c} **GPU-PBD** \\ **(Double-Sided)** \\ \end{tabular} \\ \hline Double-Sided Cloth Support & X & X & O \\ Hand Mesh Collision Handling & X & X & O \\ RoomMesh (Reality Mesh) Collision Handling & X & X & O \\ Fine-Grained Constraint Adjustment & Limited & O & O \\ Compute Shader Extensibility & X & O & O \\ Real-Time Performance (Up to 32 \(\times\) 32) & O (72 FPS) & O (72 FPS) & O (72 FPS) \\ Real-Time Performance (64 \(\times\) 64 and above) & O (72 FPS) & (65 FPS at 64 \(\times\) 64) & (40 FPS at 64 \(\times\) 64) \\ \hline \hline \end{tabular}  
* **Note:** O = supported, X = not supported.  
\end{table} 
Table 4: Feature comparison between unity cloth and GPU-PBD cloth (single-sided vs. double-sided). settings is crucial, and when visual quality and functional extensibility are prioritized, the GPU-PBD system demonstrates clear superiority. The Compute Shader-based architecture of GPU-PBD particularly facilitates future additions of custom physics laws or constraint conditions, making it more suitable for research and advanced development purposes.