cjdb: A Simple, Fast, and Lean Database Solution for the CityGML Data Model

When it comes to storing 3D city models in a database, the implementation of the CityGML data model can be quite demanding and often results in complicated schemas. As an example, 3DCityDB, a widely used solution, depends on a schema having 66 tables, mapping closely the CityGML architecture. In this paper, we propose an alternative (called ...

A proposal for an improved transportation model in CityGML

CityGML, an OGC standard, is an open data model for virtual 3D city models and includes buildings, roads, terrain, water bodies, etc. While many modules are well-developed (eg buildings, bridges, tunnels), the transportation model is, based on our consultations with various government agencies and municipalities, not sufficient for most...

Modelling urban noise in CityGML ADE: Case of the Netherlands

Road traffic and industrial noise has become a major source of discomfort and annoyance among the residents in urban areas. More than 44 % of the EU population is regularly exposed to road traffic noise levels over 55 dB, which is currently the maximum accepted value prescribed by the Environmental Noise Directive for road traffic...

Generalising 3D Buildings from LoD2 to LoD1

The increasing popularity of 3D city models in navigation, urban planning, etc.,<br/>necessitates application-specific and geometrically accurate and valid models. The concept of Levels of Detail (LoDs) indicate a model’s scale of adherence to its real-world counterpart. Highly detailed datasets often contain errors or require an exorbitant...

The most common geometric and semantic errors in CityGML datasets

To be used as input in most simulation and modelling software, 3D city models should be geometrically and topologically valid, and semantically rich. We investigate in this paper what is the quality of currently available CityGML datasets, i.e. we validate the geometry/topology of the 3D primitives (Solid and MultiSurface), and we validate...

Generation of multi-LOD 3D city models in CityGML with the procedural modelling engine Random3Dcity

The production and dissemination of semantic 3D city models is rapidly increasing benefiting a growing number of use cases. However, their availability in multiple LODs and in the CityGML format is still problematic in practice. This hinders applications and experiments where multi-LOD datasets are required as input, for instance, to determine...

Establishing a national 3D geo-data model for building data compliant to CityGML: Case of Turkey

This paper presents the generation of the 3D national building geo-data model of Turkey, which is compatible with the international OGC CityGML Encoding Standard. We prepare an ADE named CityGML-TRKBIS.BI that is produced by extending existing thematic modules of CityGML according to TRKBIS needs. All thematic data groups in TRKBIS geo-data...

A CityGML extension for handling very large tins

In addition to buildings, the terrain forms an important part of a 3D city model. Although in GIS terrains are usually represented with 2D grids, TINs are also increasingly being used in practice. One example is 3DTOP10NL, the 3D city model covering the whole of the Netherlands, which stores the relief with a constrained TIN containing more than...

Improving the consistency of multi-LOD CityGML datasets by removing redundancy

The CityGML standard enables the modelling of some topological relationships, and the representation in multiple levels of detail (LODs). However, both concepts are rarely utilised in reality. In this paper we investigate the linking of corresponding geometric features across multiple representations. We describe the possible topological cases,...

Height references of CityGML LOD1 buildings and their influence on applications

The geometry of the LOD1 block model of CityGML may be represented in a multitude of valid variants, e.g. it may represent individual buildings or aggregated blocks. The geometric representations within each of these, such as the reference of the footprint of a building, are not standardised in CityGML and are not informed in the metadata. The...

Error propagation in the computation of volumes in 3D city models with the Monte Carlo method

This paper describes the analysis of the propagation of positional uncertainty in 3D city models to the uncertainty in the computation of their volumes. Current work related to error propagation in GIS is limited to 2D data and 2D GIS operations, especially of rasters. In this research we have (1) developed two engines, one that generates random...