A GPU Framework for Interactive Simulation and Rendering of Fluid Effects

swashing water, rising smoke, dancing fire, explosions or caustics. To be used in such environments, interactive simulation and
rendering techniques have to be realized on consumer class PCs.

This work aims at exploiting graphics processing units (GPUs) for this purpose. To be able to implement general techniques of
numerical computing on the GPU, a GPU abstraction for this kind of application is required. Therefore, we have developed a linear
algebra framework. This framework allows the programmer to abstract from the underlying GPU data structures and algorithms, and to
focus on the application itself rather than the GPU implementation. Based on this framework we have implemented efficient algorithms
for solving large systems of linear equations, and we have used these algorithms to solve partial differential equations such as the
wave equation or the Navier-Stokes equations on GPUs.

The proposed framework facilitates the use of numerical simulation techniques to drive real-time visual effects. By using simulation
results to advect geometric primitives on the GPU, saving displaced positions in graphics memory, and then sending these positions
through the GPU again to obtain images in the frame buffer, a variety of different effects can be generated. In combination with
particle primitives and 3D textures, for the first time ever is it now possible to simulate and render dynamic 3D effects in real
time on consumer class PCs.

In addition to physics-based simulation of fluid phenomena, new techniques to simulate optical effects caused by such phenomena will
also be presented; i.e., caustics that can appear whenever light impinges upon reflecting or transmitting material. The proposed
techniques neither require any pre-processing nor an intermediate radiance representation, and they can thus deal efficiently with
dynamic scenery and scenery that is modified, or even created on the GPU.