scholarly journals SEMI-AUTOMATIC GENERATION OF AN LOD1 AND LOD2 3D CITY MODEL OF TANAUAN CITY, BATANGAS USING OPENSTREETMAP AND TAAL OPEN LIDAR DATA IN QGIS

2021 ◽  
Vol XLVI-4/W6-2021 ◽  
pp. 77-84
Author(s):  
P. H. T. Camacho ◽  
V. M. R. Santiago ◽  
C. J. S. Sarmiento
Keyword(s):  
Test Bench ◽  
The Philippines ◽  
Lidar Data ◽  
3D City Models ◽  
3D City Model ◽  
Building Models ◽  
Tree Classifier ◽  
City Model ◽  
City Models ◽  
Building Reconstruction

Abstract. 3D city models have found purpose beyond simple visualization of space by serving as building blocks of digital twins and smart cities. These are useful to urban areas in the Philippines through diversified applications: urban planning, disaster mitigation, environmental monitoring, and policy making. This study explored the use of free and open-source software to generate an LOD1 and LOD2 3D city model of Tanauan City, Batangas using building footprints from OpenStreetMap and elevation models from Taal Open LiDAR data. The proposed approach consists of GIS-based methods including data pre-processing, building height extraction, roof identification, building reconstruction, and visualization. The study adopted methods from previous studies for building detection and from Zheng et al. (2017) for LOD2 building reconstruction. For LOD1, a decision tree classifier was devised to determine the appropriate height for building extrusion. For LOD2, a model-driven approach using multipatch surfaces was utilized for building reconstruction. The workflow was able to reconstruct 70.66% LOD1 building models and 55.87% LOD2 building models with 44.37% overall accuracy. The RMSE and MAE between the extracted heights from the workflow and from manual digitization has an accuracy lower than 1 m which was within the standards of CityGML. The processing time in test bench 1 and test bench 2 for LOD1 took 00:12:54.5 and 00:09:27.2 while LOD2 took 02:50:29.1 and 01:27:48.2, respectively. The results suggest that the efficient generation of LOD1 and LOD2 3D city models from open data can be achieved in the FOSS environment using less computationally intensive GIS-based algorithms.

scholarly journals Modelling Buildings in CityGML LOD1: Building Parts, Terrain Intersection Curve and Address Features

2021 ◽  
Author(s):  
Evgeny Shirinyan ◽  
Dessislava Petrova-Antonova
Keyword(s):  
Multiple Sources ◽  
Intersection Curve ◽  
3D City Models ◽  
Building Model ◽  
3D City Model ◽  
Building Models ◽  
City Model ◽  
Open Datasets ◽  
Multiple Domains ◽  
City Models

3D city models integrate heterogeneous urban data from multiple sources in a unified geospatial representation, combining both semantics and geometry. Although in the last decades, they are predominantly used for visualization, today they are used in a large range of tasks related to exploration, analysis, and management across multiple domains. The complexity of urban processes and the diversity of urban environment bring challenges to the implementation of 3D city models. To address such challenges, this paper presents the development process of a 3D city model of a single neighborhood in Sofia city based on CityGML 2.0 standard. The model represents the buildings in LOD1 with a focus on CityGML features of related to the buildings like building part, terrain intersection curve and address. Similar building models of 18 cities provided as open datasets are explored and compared in order to extract good modeling practices. As a result, workflows for generation of 3D building models in LOD1 are elaborated and improvements in the feature modeling are proposed. Two options of building model are examined: modeling of a building as a single solid and modeling of a building with separate building parts. Finally, the possibilities for visualization of the model in popular platforms such as ArcGIS Pro and Cesium Ion are explored.

scholarly journals Method for 3D City Building Continuous Transformation Based on an Improved LOD Topological Data Structure

2019 ◽  
Vol 8 (11) ◽  
pp. 504
Author(s):  
Siyi Li ◽  
Wenjing Li ◽  
Zhiyong Lin ◽  
Shengjie Yi
Keyword(s):  
Data Structure ◽  
Level Of Detail ◽  
Continuous Transformation ◽  
3D City Models ◽  
3D City Model ◽  
Building Models ◽  
City Model ◽  
Lod Models ◽  
Topological Data Structure ◽  
City Models

A 3D city model is an intuitive tool that is used to describe cities. Currently, level-of-detail (LOD) technology is used to meet different visual demands for 3D city models by weighting the rendering efficiency against the details of the model. However, when the visual demands change, the “popping” phenomenon appears when making transformations between different LOD models. We optimized this popping phenomenon by improving the data structure that focuses on 3D city building models and combined it with the facet shift algorithm based on minimal features. Unlike generating finite LOD models in advance, the proposed continuous LOD topology data structure is able to store the changes between different LOD models. By reasonably using the change information, continuous LOD transformation becomes possible. The experimental results showed that the continuous LOD transformation based on the proposed data structure worked well, and the improved data structure also performed well in memory occupation.

Scalable Multi-Platform Distribution of Spatial 3D Contents

2014 ◽  
Vol 3 (3) ◽  
pp. 35-49 ◽  
Author(s):  
Jan Klimke ◽  
Benjamin Hagedorn ◽  
Jürgen Döllner
Keyword(s):  
3D Visualization ◽  
High Quality ◽  
Efficient Manner ◽  
Web Based ◽  
3D City Models ◽  
3D Rendering ◽  
3D City Model ◽  
City Model ◽  
Rendering Techniques ◽  
City Models

Virtual 3D city models provide powerful user interfaces for communication of 2D and 3D geoinformation. Providing high quality visualization of massive 3D geoinformation in a scalable, fast, and cost efficient manner is still a challenging task. Especially for mobile and web-based system environments, software and hardware configurations of target systems differ significantly. This makes it hard to provide fast, visually appealing renderings of 3D data throughout a variety of platforms and devices. Current mobile or web-based solutions for 3D visualization usually require raw 3D scene data such as triangle meshes together with textures delivered from server to client, what makes them strongly limited in terms of size and complexity of the models they can handle. This paper introduces a new approach for provisioning of massive, virtual 3D city models on different platforms namely web browsers, smartphones or tablets, by means of an interactive map assembled from artificial oblique image tiles. The key concept is to synthesize such images of a virtual 3D city model by a 3D rendering service in a preprocessing step. This service encapsulates model handling and 3D rendering techniques for high quality visualization of massive 3D models. By generating image tiles using this service, the 3D rendering process is shifted from the client side, which provides major advantages: (a) The complexity of the 3D city model data is decoupled from data transfer complexity (b) the implementation of client applications is simplified significantly as 3D rendering is encapsulated on server side (c) 3D city models can be easily deployed for and used by a large number of concurrent users, leading to a high degree of scalability of the overall approach. All core 3D rendering techniques are performed on a dedicated 3D rendering server, and thin-client applications can be compactly implemented for various devices and platforms.

scholarly journals Semi-Automatic 3D City Model Generation from Large-Format Aerial Images

2018 ◽  
Vol 7 (9) ◽  
pp. 339 ◽  
Author(s):  
Mehmet Buyukdemircioglu ◽  
Sultan Kocaman ◽  
Umit Isikdag
Keyword(s):  
Large Scale ◽  
3D Visualization ◽  
Aerial Images ◽  
Model Generation ◽  
City Management ◽  
Large Format ◽  
3D City Models ◽  
3D City Model ◽  
City Model ◽  
City Models

3D city models have become crucial for better city management, and can be used for various purposes such as disaster management, navigation, solar potential computation and planning simulations. 3D city models are not only visual models, and they can also be used for thematic queries and analyzes with the help of semantic data. The models can be produced using different data sources and methods. In this study, vector basemaps and large-format aerial images, which are regularly produced in accordance with the large scale map production regulations in Turkey, have been used to develop a workflow for semi-automatic 3D city model generation. The aim of this study is to propose a procedure for the production of 3D city models from existing aerial photogrammetric datasets without additional data acquisition efforts and/or costly manual editing. To prove the methodology, a 3D city model has been generated with semi-automatic methods at LoD2 (Level of Detail 2) of CityGML (City Geographic Markup Language) using the data of the study area over Cesme Town of Izmir Province, Turkey. The generated model is automatically textured and additional developments have been performed for 3D visualization of the model on the web. The problems encountered throughout the study and approaches to solve them are presented here. Consequently, the approach introduced in this study yields promising results for low-cost 3D city model production with the data at hand.

scholarly journals Building Virtual 3D City Model for Smart Cities Applications: A Case Study on Campus Area of the University of Novi Sad

2020 ◽  
Vol 9 (8) ◽  
pp. 476 ◽  
Author(s):  
Dušan Jovanović ◽  
Stevan Milovanov ◽  
Igor Ruskovski ◽  
Miro Govedarica ◽  
Dubravka Sladić ◽  
...  
Keyword(s):  
Smart Cities ◽  
Airborne Lidar ◽  
3D City Models ◽  
3D City Model ◽  
City Model ◽  
Novi Sad ◽  
The University ◽  
The City ◽  
City Models

The Smart Cities data and applications need to replicate, as faithfully as possible, the state of the city and to simulate possible alternative futures. In order to do this, the modelling of the city should cover all aspects of the city that are relevant to the problems that require smart solutions. In this context, 2D and 3D spatial data play a key role, in particular 3D city models. One of the methods for collecting data that can be used for developing such 3D city models is Light Detection and Ranging (LiDAR), a technology that has provided opportunities to generate large-scale 3D city models at relatively low cost. The collected data is further processed to obtain fully developed photorealistic virtual 3D city models. The goal of this research is to develop virtual 3D city model based on airborne LiDAR surveying and to analyze its applicability toward Smart Cities applications. It this paper, we present workflow that goes from data collection by LiDAR, through extract, transform, load (ETL) transformations and data processing to developing 3D virtual city model and finally discuss its future potential usage scenarios in various fields of application such as modern ICT-based urban planning and 3D cadaster. The results are presented on the case study of campus area of the University of Novi Sad.

scholarly journals AN IMPROVED LOD FRAMEWORK FOR THE TERRAINS IN 3D CITY MODELS

2019 ◽  
Vol IV-4/W8 ◽  
pp. 75-82 ◽  
Author(s):  
K. Kumar ◽  
A. Labetski ◽  
H. Ledoux ◽  
J. Stoter
Keyword(s):  
Proof Of Concept ◽  
3D City Models ◽  
General Acceptance ◽  
3D City Model ◽  
Terrain Models ◽  
City Model ◽  
Definition Of ◽  
3D City Modelling ◽  
Software Prototype ◽  
City Models

<p><strong>Abstract.</strong> The Level of Detail (LOD) concept in CityGML 2.0 is meant to differentiate the multiple representations of semantic 3D city models. Despite the popularity and general acceptance of the concept by the practitioners and stakeholders in 3D city modelling, there are still some limitations. While the CityGML LOD concept is well defined for buildings, bridges, tunnels, and to some extent for roads, there is no clear definition of LODs for terrain/relief, vegetation, land use, water bodies, and generic city objects in CityGML. In addition, extensive research has been done to refine the LOD concept of CityGML for buildings but little is known on requirements and possibilities to model city object types as terrain at different LODs. To address this gap, we focus in this paper on the terrain of a 3D city model and propose a framework for modelling terrains at different LODs in CityGML. As a proof of concept of our framework, we implemented a software prototype to generate terrain models with other city features integrated (e.g. buildings) at different LODs in CityGML.</p>

scholarly journals TOWARDS WIND-SIMULATION OF VIRTUAL 3D CITY MODELS IN A COLLABORATIVE VR ENVIRONMENT

2019 ◽  
Vol XLII-4/W15 ◽  
pp. 61-66 ◽  
Author(s):  
R. Piepereit ◽  
A. Beuster ◽  
M. von der Gruen ◽  
U. Voß ◽  
M. Pries ◽  
...  
Keyword(s):  
Flow Simulation ◽  
Level Of Detail ◽  
Planning Systems ◽  
3D City Models ◽  
Building Models ◽  
Wind Simulation ◽  
Development Processes ◽  
City Model ◽  
Simulation Results ◽  
City Models

<p><strong>Abstract.</strong> Virtual reality (VR) technologies are used more and more in product development processes and are upcoming in urban planning systems as well. They help to visualize big amounts of data in self-explanatory way and improve people’s interpretation of results. In this paper we demonstrate the process of visualizing a city model together with wind simulation results in a collaborative VR system. In order to make this kind of visualization possible a considerable amount of preliminary work is necessary: healing and simplification of building models, conversion of these data into an appropriate CAD-format and numerical simulation of wind flow around the buildings. The data obtained from these procedures are visualized in a collaborative VR-System. In our approach CityGML models in the LoD (Level of Detail) 1, 2 and 3 can be used as an input. They are converted into the STEP format, commonly used in CAD for simulation and representation. For this publication we use an exemplary LoD1 model from the district Stöckach-Stuttgart. After preprocessing the model, the results are combined with those of an air flow simulation and afterwards depicted in a VR system with a HTC Vive as well as in a CAVE and a Powerwall. This provides researchers, city planners and technicians with the means to flexibly and interactively exchange simulation results in a virtual environment.</p>

scholarly journals 3D CITY MODELS FOR SUPPORTING SIMULATIONS IN CITY DENSIFICATIONS

2021 ◽  
Vol XLVI-4/W4-2021 ◽  
pp. 73-77
Author(s):  
L. Harrie ◽  
J. Kanters ◽  
K. Mattisson ◽  
P. Nezval ◽  
P.-O. Olsson ◽  
...  
Keyword(s):  
Urban Areas ◽  
Planning Process ◽  
Model Design ◽  
3D City Models ◽  
3D City Model ◽  
Neighbourhood Level ◽  
City Model ◽  
Good Living ◽  
Research Questions ◽  
City Models

Abstract. In order to meet the increasing needs of housing and services in urban areas, cities are densified. When densifying a city, it is important to provide good living conditions while maintaining a low environmental impact. To ensure this, the urban planning process should include simulations of e.g. noise and daylight conditions. In this paper we describe a newly started projected directed towards the need for quality-assured and harmonised input data to the simulations, in the form of 3D city models. The first part of the paper includes the background and research questions of the project and in the second part a tool for daylight simulations on neighbourhood level is introduced, a tool that will be utilized for evaluating the 3D city model design.

scholarly journals WHAT IS THE NEED FOR BUILDING PARTS? – A COMPARISON OF CITYGML, INSPIRE BUILDING AND A SWEDISH BUILDING STANDARD

2018 ◽  
Vol XLII-4/W10 ◽  
pp. 27-32 ◽  
Author(s):  
H. Eriksson ◽  
L. Harrie ◽  
J. M. Paasch
Keyword(s):  
Industry Foundation Classes ◽  
3D City Models ◽  
Advantages And Disadvantages ◽  
3D City Model ◽  
Information Models ◽  
Building Information ◽  
Potential Applications ◽  
City Model ◽  
Definition Of ◽  
City Models

<p><strong>Abstract.</strong> The need for digital building information is increasing, both in the form of 3D city models (as geodata) and of more detailed building information models (BIM). BIM models are mainly used in the architecture, engineering and construction industry, but have recently become interesting also for municipalities. The overall aim of this paper is to study one way of dividing a building, namely the division of a building into building parts in both 3D city models and in BIM models. The study starts by an inventory of how building parts are defined in 3D city model standards (CityGML, the INSPIRE building specification and a Swedish national specification for buildings) and in BIM models (Industry Foundation Classes, IFC). The definition of building parts in these specifications are compared and evaluated. The paper also describes potential applications for the use of building parts, on what grounds a building could be divided into building parts, advantages and disadvantages of having building parts and what consequences it can have on the usage of the building information. One finding is that building parts is defined similar, but not identical in the studied geodata specifications and there are no requirements, only recommendations on how buildings should be divided into building parts. This can complicate the modelling, exchange and reuse of building information, and in a longer perspective, it would be desirable to have recommendations of how to define and use building parts in for example a national context.</p>

scholarly journals Services Oriented Smart City Platform Based On 3d City Model Visualization

2014 ◽  
Vol II-4 ◽  
pp. 59-64 ◽  
Author(s):  
F. Prandi ◽  
M. Soave ◽  
F. Devigili ◽  
M. Andreolli ◽  
R. De Amicis
Keyword(s):  
Spatial Data ◽  
Smart City ◽  
Smart Cities ◽  
Geographical Information ◽  
Data Infrastructure ◽  
3D City Models ◽  
3D City Model ◽  
Key Factor ◽  
City Model ◽  
City Models

The rapid technological evolution, which is characterizing all the disciplines involved within the wide concept of smart cities, is becoming a key factor to trigger true user-driven innovation. However to fully develop the Smart City concept to a wide geographical target, it is required an infrastructure that allows the integration of heterogeneous geographical information and sensor networks into a common technological ground. In this context 3D city models will play an increasingly important role in our daily lives and become an essential part of the modern city information infrastructure (Spatial Data Infrastructure). <br><br> The work presented in this paper describes an innovative Services Oriented Architecture software platform aimed at providing smartcities services on top of 3D urban models. 3D city models are the basis of many applications and can became the platform for integrating city information within the Smart-Cites context. <br><br> In particular the paper will investigate how the efficient visualisation of 3D city models using different levels of detail (LODs) is one of the pivotal technological challenge to support Smart-Cities applications. The goal is to provide to the final user realistic and abstract 3D representations of the urban environment and the possibility to interact with a massive amounts of semantic information contained into the geospatial 3D city model. <br><br> The proposed solution, using OCG standards and a custom service to provide 3D city models, lets the users to consume the services and interact with the 3D model via Web in a more effective way.

Sign in / Sign up

Export Citation Format

Share Document