Non-intersecting leaf insertion algorithm for tree structure models

Akerblom, M; Raumonen, P; Casella, E; Disney, MI; Danson, FM; Gaulton, R; Schofield, LA; Kaasalainen, M

Abstract

We present an algorithm and an implementation to insert broadleaves or needleleaves to a quantitative structure model according to an arbitrary distribution, and a data structure to store the required information efficiently. A structure model contains the geometry and branching structure of a tree. The purpose of the work is to offer a tool for making more realistic simulations with tree models with leaves, particularly for tree models developed from terrestrial laser scan (TLS) measurements. We demonstrate leaf insertion using cylinder-based structure models, but the associated software implementation is written in a way that enables the easy use of other types of structure models. Distributions controlling leaf location, size and angles as well as the shape of individual leaves are user-definable, allowing any type of distribution. The leaf generation process consist of two stages, the first of which generates individual leaf geometry following the input distributions, while in the other stage intersections are prevented by doing transformations when required. Initial testing was carried out on English oak trees to demonstrate the approach and to assess the required computational resources. Depending on the size and complexity of the tree, leaf generation takes between 6 and 18 minutes. Various leaf area density distributions were defined, and the resulting leaf covers were compared to manual leaf harvesting measurements. The results are not conclusive, but they show great potential for the method. In the future, if our method is demonstrated to work well for TLS data from multiple tree types, the approach is likely to be very useful for 3D structure and radiative transfer simulation applications, including remote sensing, ecology and forestry, among others.

Citation

Akerblom, M., Raumonen, P., Casella, E., Disney, M., Danson, F., Gaulton, R., …Kaasalainen, M. (2018). Non-intersecting leaf insertion algorithm for tree structure models. Interface Focus, 8(2), 20170045. https://doi.org/10.1098/rsfs.2017.0045

• Journal Article Type: Article
• Acceptance Date: Dec 7, 2017
• Online Publication Date: Feb 16, 2018
• Publication Date: Apr 6, 2018
• Deposit Date: Jan 15, 2018
• Publicly Available Date: Jan 15, 2018
• Journal: Interface Focus
• Electronic ISSN: 2042-8901
• Publisher: The Royal Society
• Volume: 8
• Issue: 2
• Pages: 20170045
• DOI: https://doi.org/10.1098/rsfs.2017.0045
• Publisher URL: http://dx.doi.org/10.1098/rsfs.2017.0045
• Related Public URLs: http://rsfs.royalsocietypublishing.org/