Efficient Rain Simulation based on Constrained View Frustum

Realistic real-time rain streaks rendering has been treated as a very difficult problem because of various natural phenomena. Also, for creating and managing many particles in a rain streak, many resources had to be used. This paper propose am efficient real-time rain streaks simulation algorithm by generating view-dependent rain particles, which can express a large amount of rain streaks even with a small number of particles. By creating a ‘constrained view frustum’ depending on the camera moving in real time, particles are rendered only in that space. Accordingly, particles rendered well even if the camera keep moving or rotating rapidly. And a small number of particles are used, since the simulation is performed in a user-viewed limited space, an effect of simulation many particles can be obtained. This enables very efficient real-time simulation of rain streaks.