基于分形特征的虚拟植物形态建模方法研究

发布时间：2018-01-15 13:07

本文关键词：基于分形特征的虚拟植物形态建模方法研究　出处：《山东师范大学》2015年硕士论文　论文类型：学位论文

【摘要】：分形思维自古便有，但分形理论却是直到最近三十年才得以迅速发展起来的一门崭新的理论，主要描述非线性系统中无序、复杂、不规则、具有精细结构的结构形态，揭示了自然界中有序性与无序性、确定性与随机性之间的统一，为探索自然界中一些复杂结构形态所展现的发展规律和内在本质提供了新的思维和方法。分形植物是自然界的一个不可或缺的组成部分，，和人类的生活环境密切相连，其形态和功能的模拟一直是研究的热点。虽然自然界中的植物千姿百态、千汇万状，却但其结构和本质内涵大都具有分形特征，可以非常简单的使用分形理论来进行解释和研究。随着分形理论研究的深入和应用范围领域的拓展，分形植物模拟在计算机仿真、人工智能、虚拟现实、农林业研究等技术以及商业、环保、教育、娱乐等领域中得到非常广泛的关注和应用，有着非常广阔的应用前景。基于分形特征的虚拟植物形态模拟是以植物的个体或群体作为主要研究对象，并通过量化其生物学意义和结构特征来对植物的结构、形态以及植物的动态生长过程、随机生长过程等方面进行可视化模拟与仿真。基于分形特征的虚拟植物形态模拟以计算机学为中心，结合几何学、统计学、生物学、信息学等多种学科的交错研究。分形植物的研究不仅使信息农林业领得到了广阔的发展，同时也为生物学的进一步探索研究提供了有力的依据。鉴于此，基于分形特征的虚拟植物形态建模方法研究不仅可以极大的丰富分形植物建模方法，还对植物形态逼真性和有效性的表达有极其重要的使用研究价值和深远的意义。基于分形特征的虚拟植物形态建模方法实际上是利用植物自身结构的分形特征采用一定的迭代算法来生成植物模型的方法。当今分形植物建模方法主要包括：L-系统、IFS系统、粒子系统、DLA模型、参考轴模型、多尺度自助机模型等。本文是采用在分形植物建模方面更加灵活的L-系统方法，通过测量和应用实体分形植物数据，采用Logistic生长方程和MC随机方法对对植物并行的生长过程进行表达，并使用B-样条曲线对植物的弯曲性进行可行化论述，本文对基于分形特征的虚拟植物形态建模的研究工作主要包括以下五个方面： 1.对分形理论进行深入的研究和分析通过对分形理论的深入理解，总结归纳出分形的基本性质和分形的主要研究方法，分形的基本算法，以及分形植物所具有的分形特征。通过对自然界中分形植物形态的分析，深入研究分形理论和分形植物的形态模型。 2.使用L-系统方法对分形植物的生理生态模型进行建模结合L-系统在分形植物形态结构的表达上所具有优势和实际的生物学实验数据，应用L-系统表达植物的拓扑结构和几何形态，同时也可以实现分形植物动态的生长过程，不仅可以极大地丰富和扩展了分形理论和L-系统方法，同时也扩展了其它的研究领域。 3.对植物动态生长过程进行可控性建模采用Logistic生长方程和MC随机方法，通过测量真实数据得出符合植物生长的参数，并对植物生长的动态过程进行模拟。以植物生长节点为初始状态，通过参数L-系统和随机L-系统建立完整的分支的生长规则，实现虚拟植物拓扑形态的模拟。 4.在三维空间上对植物分支弯曲性表达采用B-样条曲线表达植物枝条的弯曲形态，再现植物的自然之美，使用子L-系统对植物枝条进行弯曲性控制，使得分形植物自然、逼真，更加具有立体视觉效果。 5.实验仿真与应用采用VC++对分形植物的生长进行建模，通过改进的L-系统方法来实现对不同分形植物的形态模拟。
[Abstract]:Fractal thinking has always been there, but the fractal theory is until the last thirty years to a new theory developed rapidly, mainly describes the nonlinear system disorder, complex and irregular structure, with fine structure, reveals the nature of orderliness and no order, unity between certainty and randomness. Provides new thinking and methods to explore some complex structure show the development rule and the essence of nature. The fractal plants are an integral part of nature, and the human living environment is closely connected to simulate the morphology and function has become a hot topic. Although the natural plants in different poses and with different expressions. Qianhuiwanzhuang, but its structure and essence have fractal characteristics, the use of fractal theory can be very simple to explain and research. With the research of fractal theory In depth and application area, fractal plant simulation has attracted extensive attention and application in computer simulation, artificial intelligence, virtual reality, agroforestry, and business, environmental protection, education, entertainment and other fields. It has a very broad application prospect.
Virtual plant morphology fractal simulation is to plant individuals or groups as the main research object based on the structure of the plant by quantifying the biological significance and the structure characteristics, morphology and dynamics of plant growth process, random growth process simulation and visual simulation of virtual plant morphology. The fractal characteristic of the computer learning as the center, based on geometry, statistics, biology, information science and other disciplines of staggered. Study on Fractal plants not only make information and get the broad development, but also provides a strong basis for the study of biology for further exploration. In view of this, fractal rich plant modeling method study on fractal features of the virtual plant morphology based modeling method can not only greatly, but also has extremely important realistic on plant morphology and effective expression Research value and far-reaching significance.
Based on the fractal characteristics of the virtual plant modeling method is actually using the method of fractal characteristics of plant structure using the iterative algorithm to generate a certain plant model. The fractal plant modeling methods include: L- system, IFS system, particle system, DLA model, reference model, multi scale self machine model is adopted in the paper. L- method is more flexible in terms of fractal plant modeling, through the measurement and application of solid fractal plant data, MC growth equations and stochastic methods on the growth process of plants were expressed by Logistic in parallel, and discusses the feasible bending of plants using the B- spline curve, this paper research on virtual plant modeling based on fractal features mainly include the following five aspects:
1. in depth research and analysis of fractal theory
Through in-depth understanding of fractal theory, summarizes the main research methods and basic properties of the basic algorithm of fractal, fractal, and the fractal plant fractal characteristics. Through the analysis of the nature of fractal plant shapes, shape model research on fractal theory and fractal plants.
2. using the L- system method to model the physiological and ecological models of fractal plants
According to the experimental data and the actual biological advantages of the L- system has the expression of morphological structure of fractal plants on the topology and geometry of plant expression using the L- system, but also can realize the dynamic growth process of fractal plants, not only can enrich and expand the fractal theory and method of L- system, at the same time expand other research fields.
3. controllable modeling of plant dynamic growth process
With the method of stochastic growth equation and MC Logistic, through the real data measured with plant growth parameters, and the dynamic process of plant growth simulation. In order to plant growth nodes as the initial state, the establishment of a complete branch through the parameters of L- system and stochastic L- system growth rule, realizes the simulation of virtual plant topology.
4. flexural expression of plant branches in three-dimensional space
The B- spline curve is used to express the bending form of plant branches, reproduce the natural beauty of plants, and use the sub L- system to control the bending of plant branches, making fractal plants natural, realistic and more stereoscopic.
5. experiment simulation and Application
The growth of fractal plants was modeled by VC++, and the morphological simulation of different fractal plants was realized by the improved L- system method.

【学位授予单位】：山东师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：O189

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