Research On Plant Growth Model Based On The Combination Of L-system And Sketch

Fractal theory is a new subject developed in the past few years, which can describe the rough and irregular geometric objects in the nature or in nonlinear system. The plant, as the most important component of the nature, closely relates to human's survival and development. Although the shapes of plant that has various species are different, they have the common characteristics of self-similarity and self-reproduction. The introduction to fractal theory opens up a new way for computer simulation of plants. With the development of fractal theory, plant simulation based on fractal has become an important subject in the field of computer simulation.At present, there are four main methods for plant simulation based on fractal theory, such as modeling methods based on fractal geometry, reference axis technique, sketch and image. L-system that is skilled in representing plant form and structure is just the key among many research methods in this field. It was put forward in 1968 by Lindenmayer as a method of describing plants when he studied the evolution and structure of plant morphology. Originally, it only emphasized plant topology, that is, the neighborhood relations between plant modules. Subsequently, some geometric interpretations were introduced into the description process, which formed L-system. In 1984, Smith first applied it to computer graphics for creating plants, and thus became an effective way to simulate plants.The dissertation does much research on the definite L-system, stochastic L-system, parametric L-system and context-sensitive L-system. Based on the theory of L-system and in terms of the features of plant structure, this paper comes up with a new thinking of improving the traditional L-system algorithm and designs a method for plant modeling based on sketch, in order to achieve the unity of form of trunk and lateral branch, and then combines the improved L-system and sketch modeling, thereby realizing the control for construction of plant growth model by interactive and high efficient mode. Furthermore, in order to achieve the realistic rendering of plant, fractal recursion algorithm is used to construct three-dimensional plant model and 3D visualization is realized in VC++6.0 by using the standard graphical software interface of OpenGL and programming technology of graphics (such as texture mapping, illumination model, and material etc.).The simulation of plant appearance is the main direction in this paper, which makes exploration and research on plant modeling using a spot of botany knowledge, so as to achieve the aim of really reflecting morphological characteristics of plant growth.