Real-Time Animation of Water

Overview

Real-time rendering of realistic motion of fluids is one of the methods which immerse a player into an interactive application such as computer games. Interaction of fluids with rigid bodies is important because fluids and rigid bodies move influencing each other. Fluid simulation based on Computational Fluid Dynamics (CFD) is useful for rendering plausible behaviour of fluids. However, due to the high computational cost of CFD real-time rendering of fluids needs fast simulation. This paper shows the particle-based fluid simulation based on Smoothed Particle Hydrodynamics including interaction between fluids and rigid bodies, its fast implementation and how to render realistic water surface with optical phenomena such as reflection, refraction and Fresnel effect. The proposed method enables real-time animation of water with rigid body interaction.

The demo binary shows it can handle 2000 particles at about 30 fps on Pentium 4 2.8GHz. And you can interact with the fluids by dragging.

Key Features

Physically Based Animation

Generates visually plausible animation of fluids by physically based animation.

Particle-Based Fluid Simulation & Fast Implementation

Fast simulation enables real-time simulation. The proposed method uses particle-based simulation based on Smoothed Particle Hydorodynamics. This realize fast simulation.

Simulate Rigid Body as a Set of Particles

The rigid body is simulated as a set of particles. The rigidity constraint enforce particles of rigid body behaves as a rigid body. This can easily simulate interaction of fluids with rigid bodies.

Shading by programmable graphics processor

GPU enables the optical phenomena such as reflection and refraction on the water surface.

Screenshots

Interaction with wood

Interaction with stone

System Requirements

• Microsoft Windows 2000 or later
• Intel x86 Compatible Processor
• OpenGL ARB Fragment Program and Vertex Program Currently water is not shaded properly on some ATI RADEON series

Download

• Binary version 0.4 rtfluid04.zip (1.1 MB)

  Known Issues
  - Crashes when many particles concentrate
  - Poor interface :(
  

• Captured movies: In glass (7.4 MB), Interacting with wood (2.2 MB), Interacting with stone (2.1 MB)
• Master thesis(in Japanese): mthesis.pdf (12.8 MB)

Acknowledgement

The cubemap texture included in the demo is credited to Peter Murphy. Thank you, Paul Bourke!