Tree growth visualization

Abstract

In computer graphics, models describing the fractal branching structure of trees typically exploit the modularity of tree structures. The models are based on local production rules, which are applied iteratively and simultaneously to create a complex branching system. The objective is to generate three-dimensional scenes of often many realisticlooking and non-identical trees. Our goal, instead, is to visualize the growth of a prototypical tree of certain species. It is supposed to look realistic but, more importantly, has to conform with real, measured data. We construct a tree model being similar to existing ones and extend it by coupling the branching production rules with dynamic tree-growth rules. The latter are based on equations derived from measured street tree data for London Plane tree (Platanus acerifolia) such as tree height, diameter-at-breast-height, crown height, crown diameter, and leaf area. We map the global, measured parameters to the local parameters used in the tree model. The mapping couples knowledge from plant biology and arboriculture, as we deal with trees that are trained and manipulated to achieve desired forms and functions within highly urbanized environments.