Research On Real Time Rendering Of Realistic Tree

Research on real time rendering of realistic tree is a focus field of computer graphic all the time, because complicate detail structure of tree makes it very difficult to model, store, rendering. Real time rendering of realistic has two indexes: realistic and real-time, and the two indexes are often a pair of contractions.In realistic, based that tree is formed hierarchical structure by trunk, branch and leaf on the macroscopical shape structure, this paper presents a topological structure which describes the relationship between all the branches. On this basis, it utilizes drawing function of smooth and close curve of three B spline curve surface to construct the surface of branch. Regards the surface of every branch as a cylinder, and makes the different cylinder link together according to the relation among the branches to form an intact tree. The texture of tree is mainly finishes by surface color texture. Leaves adopt the method of combining together texture mapping and bmp picture transparence disposal to rendering, which can reach higher realistic effect.In real-time, this paper presents a method on tree rendering based dynamic impostor technology. This method firstly projects to the plane to create the plane of impostor based tree model, secondly maps the texture on the plane of impostor which has created, thirdly forms tree image through rendering impostor texture plane. When reference viewpoint moves, it can decide whether dynamically update the content of impostor plane according error metric. In addition, it utilizes the thought of store point, stores model view coordinate, texture coordinate, normal coordinate of basic plane of tree in the array to change model view coordinate of tree, and reads point of the array to create a new tree to finish the fast rendering work of many trees.