A Simple but Effective Algorithm to Model the Competition of Virtual Plants for Light and Space

William Van Haevre
University of Limburg - Expertise centre for Digital Media
Wetenschapspark 2
3590 Diepenbeek

e-mail: william.vanhaevre@luc.ac.be



Keywords: L-systems, tree modelling, photomorphogenesis, natural phenomena, light interaction, photons, environment sensitivity, plant representation


We present a simple but effective algorithm to simulate plant growth in a realistic way, taking into account illumination, spatial occupancy and the nearby presence of other plants. The basic idea of our algorithm is to simulate light flow during all stages of plant development, by tracing virtual photons emitted by light sources in the same way as it is done in many global illumination algorithms. We augment the L-system, modelling plant growth, with a mechanism for determining predominant illumination directions by analysing the distribution of the direction of incidence of photons hitting plant parts. Based on photomorphogenesis principles found in literature, the same photons are used to “discourage” plants from growing into each other by penalizing the contribution of photons reflected of other plants. At this time, our algorithm is implemented using the very simplest solutions at all stages. Nevertheless, first experiments show that the approach is promising. In future work, the algorithm proposed here will be refined considerably in various ways.