Procedural architecture using deformation-aware split grammars

Abstract

With the current state of video games growing in scale, manual content creation may no longer be feasible in the future. Split grammars are a promising technology for large-scale procedural generation of urban structures, which are very common in video games. Buildings with curved parts, however, can currently only be approximated by static pre-modelled assets, and rules apply only to planar surface parts. We present an extension to split grammar systems that allow the creation of curved architecture through integration of free-form deformations at any level in a grammar. Further split rules can then proceed in two different ways. They can either adapt to these deformations so that repetitions can adjust to more or less space, while maintaining length constraints, or they can split the deformed geometry with straight planes to introduce straight structures on deformed geometry

A Survey of Algorithmic Shapes

“…RENÉ ZMUGG et al introduced deformation-aware shape grammars, which integrate deformation information into grammar rules [57]. The system still uses established methods utilizing planar primitives and splits; however, measurements that determine the available space for rules are performed in deformed space.…”

Built by Algorithms – State of the Art Report on Procedural Modeling –

“…RENÉ ZMUGG et al (2013) introduced deformation aware shape grammars, which integrate deformation information into grammar rules. The system still uses established methods utilizing planar primitives and splits, however, measurements that determine the available space for rules are performed in deformed space.…”

Domain specific methods for procedural modeling of historical architecture

“…Procedural Architecture using Deformation-Aware Split Grammars One of the limitations of previous split grammar systems is the fact that the only method of approximating the curved features of buildings was via static premodeled assets, with rules applying solely to planar surfaces. In contrast, the new system presented by Zmugg et al in the papers Deformation-aware split grammars for architectural models [97] and Procedural architecture using deformation-aware split grammars [98] allows free form deformations to be defined in the grammars. The deformations are not merely a post-processing step that deforms the whole model, but can be defined at any level in the split grammar and thus the split operators can adapt the splits to the deformed space.…”

“…The papers Deformation-aware split grammars for architectural models [97] and Procedural architecture using deformation-aware split grammars [98] were written by the work group for Procedural Modeling at the Institute of Computer Graphics and Knowledge Visualisation (CGV) [46] at Graz University of Technology.…”

“…There are already existing methods that can model or approximate curved and deformed shapes (as in [87,98]). However, they have problems or fail when it comes to modeling complex or fully curved shapes as in towers, domes, vaults, etc.…”