The Research On Visual Technology Of Virtual Plant Growth

Virtual plant is computer simulation of the structural development and growth ofplants in 3-D spaces. Plants morphology is highly complex. Biological branchingpattern formation is a process that so far has gone largely unexplained. The realisticmodeling of plant is an important problem in computer graphics. The visual technologyof virtual plant growth is faithful to botany, and it adopts the image processing, virtualreality, computer simulation and other technologies to realize the virtual plants growth.It has great meaning in both theory and practice since a long time. Most of the methodsfor modeling plants growth are based on the fractal--theory, which achieved themathematic model according to the description of the self-similarity between the wholeand the local part of the plants. There are three approaches typically used in visualsimulation of virtual plant: iterative function, L-systems and particle systems.Nevertheless, these methods cannot satisfy all the aspects of the practical applicationrequirements, since any of these methods has its own limits and range of application.The paper is organized as follows. Firstly, this paper analyzed the foreign research progress, and compared theseimplementation methods by experiments. Secondly, this paper analyzed the iterative function,particles system and L-systemmodels. The iterative function model has strong description ability, but its iteratedfunction can be hardly acquired. L-systems are one of the better-known proceduralmodels and extremely powerful tools for they are closest to the biological simulationsand provide visually extremely plausible results. But L-systems seem to be a kind ofprogramming language but without data structures and with very low control over theproduction process. As in the case of L-systems, the particle systems were closedallowing no interaction between particles and an environment. This paper presented anew plant growth model— — EasyL-System, which based on L-system and 3Dreconstruction. Thirdly, the paper designed a model for the plant organs. The following are themain steps of modeling. First of all, these organs' characters have been extracted fromimages. Then, plants organs meshes can be reconstructed, which can be interactivefreeform deformation of the model. On the basis of this method, the experiments ofleaves' organ modeling have been carried out successfully, and give the result.重庆大学硕士学位论文 英文摘要　 Fourthly, the paper successfully developed the virtual plants growth system(VP-1.0) based on the organ model. The input of this system is the grammar ofEasyL-system and the plant organs mesh, the output is the plant model in 3D scene. Inaddition, this system allows users to configure camera position and lights parameters, sothat the users can look this plant model from different angles and positions. In the end, the paper gives the conclusion and some suggestions about future work.