## 3 Results and Discussions
### Immersive Visualization Systems  
The presence of rainfall (Figure 5) and snowfall (Figure 6) particle systems is not crucial to the display of hydrological data, but it is important for the creation and maintenance of user immersion. The presence of these systems gives the digital environment a sense of realism and dynamism, which allows users to become more immersed in the simulated world than they could with the absence of dynamic weather [32]. User immersion is a key consideration in this model, as it has been found to increase cognitive performance and reduce the adverse effects of simulation use [31] ([PERSON] et al., 2023). The visualization of precipitation in this project is currently a static, visual phenomenon and does not have complex interactions with the terrain or with other data visualization and simulation systems. Future work on this system will prioritize implementing default visualizations that correspond to real-world weather data, thus allowing users to see local weather conditions in real time and then configure these visualizations if they choose to do so. Additionally, future work will aim to connect the weather visualizations to the fluid simulation system, allowing for a more seamless and holistic simulation of complex hydrological interactions. The precipitation configuration script (Figure 7) allows users to control aspects of the particle system that are relevant to the graphical attributes of the precipitation. By implementing this script, other factors of the particle system that are not relevant can be stripped, reducing the likelihood of users becoming confused when trying to adjust the precipitation attributes. Allowing users to control these graphical attributes should allow for visualization to be catered to the needs of the user and their specific scenario. Additionally, this script acts as the foundation for implementing control of these graphical systems during runtime. Future work on this project will make these attributes accessible to users within the game world through a control panel user interface. This would allow these attributes to be configurable on the fly, without needing to be initialized before runtime or modified in the Unity editor. The configuration script is easily modifiable and can be changed to accommodate other visualizations that use Unity's particle system. Figure 5: Rainfall particle system at: (**a**) low; and (**b**) high intensity configurations. Figure 6: Snowfall particle system at: (**a**) low; and (**b**) high intensity configurations. The Zibra Liquids plugin provided effective real-time fluid simulation. The fluid is simple enough to configure and can be controlled well via scripting. The major issue with using this plugin was the inability to add collisions to the simulation at runtime. This limitation, although partially resolved, has been quite a setback to the progress of this application due to the terrain provided by the Maps SDK being entirely dynamically generated. Additionally, because terrain tiles can display a wide variety of topographic features, often the prebuilt collision boxes provided were not enough to create entirely emergent visualizations of hydrological processes. The 'Neural Colliders' offered by the plugin allow for the generation of more complex collision meshes, but this is more suited towards facilitating collisions between key set-piece assets. Because the process of creating these neural colliders must be done through the Zibra AI servers, it is not practical to generate these collision meshes for each terrain tile at runtime. Another concern for fluid simulation was considerations of scale. The Zibra Liquids plugin simulates fluids using a large number of particles. Increasing the volume of fluid to be simulated increases the particle count, thereby increasing the need for computer processing power.