Desbenoit, BrettGalin, EricAkkouche, Samir2015-02-192015-02-1920041467-8659https://doi.org/10.1111/j.1467-8659.2004.00765.xThis paper presents a system for modeling lichens and simulating their propagation and growth in a virtual scene. Lichens colonize almost every substrate in nature and play an important role in the visual appearance of a natural object. The propagation of lichens over the substrate is performed by an Open Diffusion Limited Aggregation model constrained by the characteristics of the environment. The designer can control the development of lichens with simple parameters. Rendering the complex geometry and texture of lichens is achieved by instantiating three dimensional lichen models stored in an atlas of shapes created after real world images. The lichens obtained by our approach considerably increase the realism of complex natural scenes.Categories and Subject Descriptors (according to ACMCCS):I.3.3 [Computer Graphics]:Three-Dimensional Graphics and Realism10.1111/j.1467-8659.2004.00765.x341-350