Target Shape Controlled Cloud Animation

This paper proposes a geometry-based technique to control the target shape and the motion of clouds in computer animation so that the synthetic appearance of the clouds resembles a specified three-dimensional shape. The technology for automatically generating this special effect has been desired by the movie industry for many years. Our method is based on ellipsoid decomposition. Firstly, ellipsoids are employed to approximate a given mesh model which indicates the target shape of cloud animation. After that, the target object is represented in a blobby implicit surface using ellipsoidal blobs. Finally, two geometry-based schemes are introduced to generate the cloud animations with target shape controlled in two different ways: aggregated from several pieces of clouds or diffused from one piece of cloud.

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