A unified smoke control method based on signed distance field

摘要

Smoke control involves shape and path. A unified framework able to deal with both of them will enable animators to manipulate the shape and path of smoke animation more effectively. In this paper, we develop such a unified framework. With our approach, path control, shape control, and mixed control of both can be handled satisfactorily in the same framework. In order to develop this framework, we use a signed distance field to provide three control forces: path control force, boundary control force, and shape control force based on medial axis point clouds. The path control force makes the smoke move along the appointed route, the boundary control force keeps the smoke moving through specified regions only, and the shape control force enables the smoke to form various given shapes. The boundary control force and the shape control force are two novel control forces developed in this paper. To make the smoke form the target shape more accurately, we develop an adaptive strategy to adjust the divergence field. We also employ a new hybrid vortex particle scheme to enhance the turbulence flow details. The examples given in this paper indicate that our proposed framework is advantageous over the existing shape control approaches and path control algorithms, and a naive combination of the two.