Realization and Extension of the Xfrog Approach for Plant Modelling in the Graph-Grammar Based Language XL

Two well-known approaches for modelling virtual vegetation are grammar- based methods (L-systems) and the Xfrog method, which is based on graph transformations expanding \multiplier" nodes. We show that both approaches can be uni ed in the framework of \relational growth grammars", a variant of parallel graph grammars. We demonstrate this possibility and the synergistic bene ts of the combination of both methods at simple plant models which were processed using our open-source software GroIMP.