Ontology-based Procedural Modelling of Traversable Buildings Composed by Arbitrary Shapes

Abstract

University of Trás-os-Montes e Alto Douro Albert EinsteinTo my family and friends To my soulmate Dércia vii UNIVERSITY OF TRÁS-OS-MONTES E ALTO DOURO PhD in Computer ScienceThe members of the jury recommend to the University of Trás-os-Montes e Alto Douro the acceptance of the thesis entitled "Ontology-based Procedural Modelling of Traversable Buildings Composed by Arbitrary Shapes"accomplished by Telmo Miguel Oliveira Adão in partial fulfillment of the requirements for the degree of Doctor Philosophy. December 2015Jury President:Professor Abstract -3D virtual models of buildings are commonly used in areas such as architecture and video games to preview a house project and to populate a virtual scenario, respectively. Traditionally, the production of these models requires highly skilled manpower and a considerable amount of time. To address this issue, many researchers have developed semi-automatic techniques to produce virtual models expeditiously. These procedural techniques provide different ways of generating buildings, including interiors and outer facades, to serve several purposes (e.g., content generation for video games or archaeological reconstruction). However, the existing techniques focusing on building interiors usually only support the generation of floor plans constrained by regular shapes or contour polygons obtained from rectangles sets. At the same time, the possibility of modelling interior rooms through the specification of its constraint walls remains poorly explored. Moreover, most of the existing procedural generation solutions are guided by complex grammars concerned with geometrical aspects or semantic structures that fit specific project requirements, apparently disregarding the established standards for virtual urban environments, specifically, CityGML.To overcome the noted issues, a novel procedural modelling methodology is proposed in this thesis, one that produces virtual models of buildings, including exteriors outlined by arbitrary shapes and interiors formed by convex polygons. Methodology's regulation is provided by a building ontology -a CityGML-based knowledge structure, planned to be extensible to specific architecture styles -through several guiding data structures such as structured XML and ontology-based grammar. Regarding the supporting process, a treemap approach is used to subdivide the building layout into floor plan areas. During the development of this work, several improvements were progressively made to the treemap in order to enable the subdivision of different constraint polygon types which range from rectangles to arbitrary shapes. Moreover, in the most mature work stage, a method concerning inner room walls adaptation is addressed. Next, a set of operations is performed, from the marking transitions step to the extrusion process that provides the 3D aspect. In addition, an experimental stochastic approach is proposed to automate the production of random buildings using this procedural modelling methodology.A set of tests was made to demonstrate the capabilitie...

Procedural Modeling of Buildings Composed of Arbitrarily-Shaped Floor-Plans: Background, Progress, Contributions and Challenges of a Methodology Oriented to Cultural Heritage

“…Relying on a graph approach to design generation (GADG), a solution to enable the production of rectangular floor-plans that can be further improved or customized was proposed [108]. Recently, an ontology-based procedural modeling methodology, capable of generating virtual one-story buildings, including exteriors outlined by arbitrary shapes and interiors formed by convex polygons, was presented [12]. In this paper, the mentioned methodology [12] is briefly revisited for contextualization purposes, and then, the integration of the virtual buildings procedurally modeled as the methodology's outcomes for other projects (also carried out by most of this paper's authors) is addressed.…”

“…Recently, an ontology-based procedural modeling methodology, capable of generating virtual one-story buildings, including exteriors outlined by arbitrary shapes and interiors formed by convex polygons, was presented [12]. In this paper, the mentioned methodology [12] is briefly revisited for contextualization purposes, and then, the integration of the virtual buildings procedurally modeled as the methodology's outcomes for other projects (also carried out by most of this paper's authors) is addressed. Afterwards, improvements that enabled the production of buildings with straight skeleton-based roofs pursuing a more natural look are presented.…”

“…The virtual models outputted by those methodologies are of major importance in research and business fields like architecture, archeology, or video games, to satisfy different requirements, such as expeditious building generation for extensive virtual environment production and hypothesis testing based on virtual reconstructions.Despite the many achievements of the existing procedural modeling approaches, most of them still lack support of the generation of virtual buildings with both exteriors and interiors composed of arbitrary shapes-non-rectangular shapes (convex or concave n-gons)-at the floor-plan level. Considering the limitations, new processes and techniques, capable of properly supporting some relevant tasks (e.g., digital preservation of cultural heritage or extensive virtual urban environments production), specifically those involving the generation/reconstruction of virtual buildings with irregular geometric requirements, were developed in a methodology that considers ontology-based grammar rules as input to derive coarse 3D building models externally constrained by arbitrary shapes and having internal divisions delimited by convex shapes [12]. Regarding the generation process, an adapted treemap approach is used to subdivide the building layout into floor-plan areas, ranging from rectangles to arbitrary shapes.…”

“…Then, a set of operations is performed, from the marking transitions' step to the walls' extrusion process, which provides the 3D aspect. Rather than validating architectural rules, this work aimed to provide a particular class of specialists-namely archeologists and multimedia professionals-the freedom to timely propose and iteratively refine virtual models, until the achievement of plausible hypotheses.The proposed procedural modeling methodology [12] work started to be delineated in [13,14] and passed through a few enhancements [15,16] until more recent versions [12,17]. This methodology had its first implementation in the "Expeditious Reconstruction of Virtual Cultural Heritage Sites" (ERAS) research project (PTDC/EIA-EIA/114868/2009), which focused on the virtual reconstruction of Roman buildings [18].…”

“…The proposed procedural modeling methodology [12] work started to be delineated in [13,14] and passed through a few enhancements [15,16] until more recent versions [12,17]. This methodology had its first implementation in the "Expeditious Reconstruction of Virtual Cultural Heritage Sites" (ERAS) research project (PTDC/EIA-EIA/114868/2009), which focused on the virtual reconstruction of Roman buildings [18].…”