Construction And Rendering Of Realistic Feathers

Generation of photo-realistic images of virtual nature scenes is a challenging topic in computer graphics. It has been found wide application in many domains such as computer games, battlefield simulation, special effects of movie, landscaping, architecture and virtual reality, etc. However, there is no a uniform method to render the nature scenery include trees, feathers, rain, fog, fire, etc. But to get models of the nature scenery with reality effect, a geometry model has to be constructed by computer, then the luminosity of the surface of it be calculated according to the environment situations, by doing this, the design image may show a vivid effect. Factors concerning the image of feathers were thoroughly analyzed in this investigation. Based on the work of our predecessors, the paper presents a novel method to model Realistic Feathers.First, two-dimensional feather is modeled with a collection of Hermite curves, which makes rending of feathers be more convenient based on vector character of Hermite curves. Only by variation of some parameters, all sorts of feathers can be generated automatically. In order to improve the reality of feather, it supplies the barbs with texture. And on the basis of two-dimensional feather, a three-dimensional feather model is constructed for the first time according to its structural characteristics. It is realized with three-dimensional Hermite curves. Furthermore its using method is as easy and clear as two-dimensional feather. However, just used a collection of Hermite curves, resulting are dissatisfactory. Because means of reality are lacking, such as illumination, self-occlusion and self-shadow, etc. The paper presents an approach to bidirectional texture function synthesis of fine details, which have approximately regular structures of the feather in fine scale. Namely based on basic framework of Hermite curves, mathematical model can be established and meshing it. We obtain geometric structure of the feather. Lastly, Realistic Feathers of the BTF is synthesized over the generated detail surface of the feather for each given view and light direction. Applications of the feathers have been given in the end of this paper. The wings are constructed by two-dimensional feathers and feather coats are simulated based on three-dimensional feathers. And some future research directions have been pointed out.