Visually Realistic Rain Modeling Optimization for VR Application

Simulation purposes are to create an event in the world as real as possible, and by using Virtual Reality Technologies, it can achieve a higher level of realism and immersion. By using particle Systems from Unity can be used to producing a phenomenon that involving a small moving object on a big scale such as smoke, fire, or rain. However, when trying to use the particle system, sometimes the performance got reduced because there are too many particles working at the same time and result in a frame rate drop that causing discomfort to the player. For this reason, it's essential to optimize the performance by limiting objects that are needed to draw to lighten up the GPU process. In this paper, we discussed how to produces rain using the particle system in unity and find the best way to simulating rain with the best frame rate. We will show how the lifetime of the particle affecting the cycle of the particle system and the impact on the particle emission. We concluded that it's essential for developers to focus on the balance for creating realistic and detailed simulation and the stability of the simulation performance so the player can be more comfortable and immersive.