Fast Shaping Of Flowers Based On Parametric Modeling And Development Of The Generated System Of Animation

With the development of the computer simulation technology, more and more natural scenery can be modeled and emulated in the virtual environment. Flowers, the most common ones in the natural scenery, are possessed of intricate structures, random forms, and various kinds of combination modes. The current methods of flower modeling and emulating mostly have much weakness for their complicated algorithm, large calculation, too much manual intervention and high demand of techniques. They can hardly model and emulate complicated plants such as flowers speedily, which has greatly limited the presentation of flowers in the virtual scene. This thesis brings forward the fast modeling of parametric flowers based on topology feature extraction and the technology of animation simulation. Without using complicated modeling skills but merely the revision and alteration of the parameter, the user can complete the designing of the flower's forms and the emulation of the animating flowers. This thesis has done detailed research on the following aspects:1. Feature extraction methods of flower shapes have been given. Though the natural flowers vary in their shapes and kinds, they share likeness and repeatability in their structures and forms to some degree. With regard to these characteristics, this thesis proposes the descriptive means of flower shapes based on the topological structure and the fast parametric shaping of flowers based on components. This approach of flower description and generation based on the topological structure can not only speedily present intensely realistic flower forms but also conveniently occlude the local, clouding the judgment and avoiding the false effect of the flower's penetration of other objects.2. The flower material store has been constructed, which has provided material for the following flower shaping and animation emulation. By using the feature extraction methods of the flower forms raised in this thesis, and the techniques such as the grid division and feature skeleton extraction, the natural flowers can be dealt with in a fast and convenient way, forming material nodes that fall into the material store. In addition, necessary common interface needs to be designed in order to use the existing shared recourses to the fullest extent. In this way, the flower material can be imported from the various kinds of existing stocks that possess different formats conveniently, a value to the parameter assigned, and the feature designed accordingly.3. Parametric flowers have been shaped. The outline of the flower forms can be rapidly created by following the methods of describing flower shapes mentioned above and the required geometric topology of the flower shapes. Then, the highly realistic flower models can be produced if the key nodes are replaced by the material nodes in the stock. The realistic sense of the flower structure is guaranteed by the parametric model; and the third dimension of the flower in its appearance is ensured by all kinds of material nodes of the stock. The user can change both the structure and appearance of the flower rapidly merely by the need of alternating the model parameter and choosing different material nodes.4. The animation emulation of the flower has been realized. This thesis raises an approach of analyzing the motion of the model nodes located in different places through simplified physical models and assigning the nodes various animation control properties on the basis of the parametric flower structure models. The animation with realistic and real-time sense can be created by the usage of the key-frame animation and the setting of its attribute properties. The effect of the flower's dancing in the wind can be easily created through this way.Through the Re-develop Technology, the means of flower feature extraction and fast modeling and the technology of animation emulation have already been realized as the Maya Plug-in procedure. And the primary results shown in practice have certified the correctness and effectiveness of the means and technology proposed in this thesis.