Declarative procedural generation of architecture with semantic architectural profiles

Abstract

Procedural content generation (PCG) for architecture is widely used in a variety of digital media, most notably in games. However, such methods are often limited in their expressive range, and require considerable technical knowledge to create non-trivial architectural structures. We present a novel tile-based PCG approach for generating architecture, that proposes the use of architectural profiles, a declarative characterization of architectural typology, within a generic tile solving framework. An architectural profile consists of a set of tiles, representing atomic architectural building blocks, and a set of declarative constraints and rules, specifying which conditions a tile configuration has to satisfy to be valid. These conditions are translated into logic constraints, and used by a tile solver to control tile placement in a bottom-up manner. Eventually, each valid model output by the solver is a representative instance of its architectural profile. We describe an implementation of this approach with Answer Set Programming, using an off-theshelf constraint solver for model generation. We performed an expressive range analysis, and concluded that our declarative method is quite controllable and can be steered over a broad range of architectural structures, regarding density and repetitiveness. Due to this expressive range and control, our tile-based method is very suitable for the customized development of urban environments for games.

Recent Advances in Procedural Generation of Buildings: From Diversity to Integration

“…■ Special Purpose Language means that users have to learn and use a special purpose language, such as the selectionexpression commands of the procedural modelling language SelEx as in [54]. ■ Formal Configuration means that users have to design formal rules, encoded, for instance, in logical expressions, or mathematical constraints as in [55]. ■ Parametric Configuration means that the core task of the user is to tweak parameters of the generator, e. g. setting parameters such as building width, length, shape etc.…”

“…Providing some given data may simplify the overall process in terms of amount, adaptation, and diversity of the generation efforts. Yet, the availability of the respective data sets, in sufficient type, number, and quality, needs to be warranted in the first place [55]. Some approaches might only require external data once, e. g. to train a Bayesian network one time and to use it repeatedly in subsequent generative steps [30].…”

“…■ Predefined Building Blocks means that prepared assets are arranged and properly combined. van Aanholt et al arrange tiles (e. g. stairs and wall fragments) by a solver according to their properties [55]. ■ Pixels / Images means that images or pixels of images are processed for generation.…”

The AI Settlement Generation Challenge in Minecraft

“…Among our competitors are hobbyists and academic researchers, and in particular university students who have created a generator as part of their coursework. Some of the past approaches that have been used or developed for the GDMC competition have been published as peer-review papers [9,29].…”