Large-scale Shallow Water Control

Abstract

The research area of water simulation control is focused on controlling the flow of computer-generated water. Current studies in this area are heavily skewed towards off-line applications. While there are studies that achieve control in real-time, in practice this is limited to small-scale scenarios. This thesis presents a simple technique to control shallow water simulations on a large scale in real-time.

The water control technique presented by this thesis works on any type of water simulation that stores its properties in a grid-based format. The technique is based on splitting the low and high frequency components of the water state through convolution with a low-pass filter. Additionally, to maintain existing water flow details, control is applied in a weak form by linearly interpolating the current water state with a target state.

We show that the technique produces similar results to an uncontrolled water simulation that is based on the same input. Furthermore, we show that important small-scale wave details of the water simulation are maintained for an extended period of time, while large-scale interruptions are quickly dealt with. Performance of the technique relies on the size of the grid, but is real-time when running on a single CPU for a typical flooding scenario of 128 by 128 cells.