Interactive Simulation Of Large-scale Liquid-photorealistic Rendering Research And Implementation

Along with the constant development of computer graphic, people are able to realize"photorealistic"virtual environment with computer. In order to further enhance the immersion, the interactivity becomes current focus of study. Physical simulation had fundamentally changed the interactivity of environment, but the huge computation of physical simulation and the real-time requirement become contradictory, and the large scale scenes have intensified it. The contradictory is very significant in fluid simulating. This paper focuses on simulating large scale liquid, like lake, ocean, and seeking the equilibrium point of reality and efficiency.Large scale liquid simulation is a very important study field of modern graphics. This paper demonstrates several kinds of major model, including geometric model, physical model, spectrum analyze and Perlin noise. Wave simulation, large scale achieve, two ways coupled liquid solid interaction and rendering.This paper is mainly about the following three aspects of the study:Free wave simulation on the liquid surface. Perlin noise is used to control every height field point's position. The continuous variation of Perlin noise is able to create smooth waves. Experience results that the computation of this method is low enough to meet the real-time requirement, and waves are really like ocean waves without strong wind.Infinite scale and liquid solid interaction. Using the spirit of projection, the rectangle area of waves is extended to cover the observer's field of vision. This will create an illusion of infinite scale. The collision reflection of liquid is simulated by solving two-dimension wave equation, and overlaid with free wave surface slidably. The computation of rigid body's buoyancy is based on discrete volume. Experience results that, separating volume of any shaped rigid body to its bounding box's vertexes is able to simplify computation and ensure the reality.Rendering. Realize reflection of surface with GPU. Reflection can be divided into environmental reflection and light source reflection. Cube mapping can be used to simulate reflection of sky, and Phong model is able display sparkling surface. The movement and liquid solid interaction is computed by CPU in order to meet different requirement of various kinds of software and hardware environment. All the render works are computed by GPU. The experience results reality scene and low CPU cost.Finally, this paper analysis problems and deficiencies, and advance the direction of improvement.