Characteristics of models that impact transformation of BIMs to virtual environments to support facility management operations
Abstract
Building information models (BIMs) have been used by the Architectural/Engineering/Construction (AEC) industry with a focus on storing and exchanging digital information about building components. However, the untapped potential of BIMs in facility operations and the experience of facility operators while they interact with digital building information have not been understood widely. One of the underlying bottlenecks in the use of BIMs in the FM phase is the lack of interactions with components to easily access information of interest, and the lack of ways to navigate in models with full spatial understanding. Virtual environments (VEs), which represent physical spaces digitally in virtual worlds, enable interactions with virtual components to access information with spatial understanding. The underlying challenges in the conversion of BIMs to VE hinder a streamlined process. This paper provides a detailed analysis of building size, geometric complexities of discipline models and level of geometric granularity as factors contributing to inefficient transformation of BIMs to VE. The paper also provides research findings on a set of computational approaches such as polygon reduction and occlusion culling to overcome challenges and improve the data transfer faced in converting BIMs into VEs over a range and size of facility models.
Keyword : BIM, virtual reality, facility management
How to Cite
Zou, Z., Arruda, L., & Ergan, S. (2018). Characteristics of models that impact transformation of BIMs to virtual environments to support facility management operations. Journal of Civil Engineering and Management, 24(6), 481-498. https://doi.org/10.3846/jcem.2018.5689
This work is licensed under a Creative Commons Attribution 4.0 International License.
References
Autodesk. 2017. Detail levels in Revit [online], [cited 21 May 2017]. Available from Internet: https://www.autodesk.com/view/rvt/2017
Behzadan, A. H.; Timm, B. W.; Kamat, V. R. 2008. General-purpose modular hardware and software framework for mobile outdoor augmented reality applications in engineering, Advanced Engineering Informatics 22: 90–105. https://doi.org/10.1016/j.aei.2007.08.005
Bern, M.; Eppstein, M. 1992. Mesh generation and optimal triangulation, Computing in Euclidean Geometry 1: 23–90. https://doi.org/10.1142/9789814355858_0002
Bille, R.; Smith, S.; Maund, S.; Brewer, G. 2014. Extending building information models into game engines, in Proceedings of the 2014 Conference on Interactive Environment, 2–3 December 2014, Newcastle, NSW, Australia, 1–8. https://doi.org/10.1145/2677758.2677764
Billger, M.; Heldal, I.; Stahre, B.; Renstrom, K. 2004. Perception of color and space in VR: a comparison between a real room and virtual reality models, in Proceedings of SPIE – The International Society for Optical Engineering, 2–3 August 2004, Denver, CO., USA.
Bowman, D.; Ray, A.; Gutierrez, M.; Mauldon, M.; Dove, J.; Westman, E.; Setareh, M. 2006. Engineering in three dimensions: Immersive VEs, interactivity, and 3D user interfaces for engineering applications, in Proceedings of GeoCongress, 26 February –1 March 2006, Atlanta, Georgia, 1–17.
Chen, H. M.; Hou, C. C.; Wang, Y. H. 2013. A 3D visualized expert system for maintenance and management of existing building facilities using reliability-based method, Expert Systems with Applications 40(1): 287–299. https://doi.org/10.1016/j.eswa.2012.07.045
Chen, J. C.; Thropp, J. E. 2007. Review of low frame rate effects on human performance, IEEE Transactions on Systems, Man and Cybernetics, Part A: Systems and Humans 37(6): 1063–1076. https://doi.org/10.1109/TSMCA.2007.904779
CIC. 2014. Computer integrated construction research group- workflow of exporting Revit models to Unity. Penn State CIC Research Group.
Dalton, B.; Parfitt, M. 2013. Immersive visualization of building information models. Design Innovation Research Center Working Paper 6 [1.0]. Reading: Design Innovation Research Centre, University of Reading.
Du, J.; Shi, Y.; Zou, Z.; Zhao, D. 2017a. CoVR: Cloud-based multiuser virtual reality headset system for project communication of remote users, Journal of Construction Engineering and Management 144(2): 04017109. https://doi.org/10.1061/(ASCE)CO.1943-7862.0001426
Du, J.; Zou, Z.; Shi, Y.; Zhao, D. 2017b. Simultaneous data exchange between BIM and VR for collaborative decision making, in ASCE International Workshop on Computing in Civil Engineering 2017, 25–27 June 2017, Seattle, Washington, USA, 1–8. https://doi.org/10.1061/9780784480830.001
Du, J.; Zou, Z.; Shi, Y.; Zhao, D. 2018. Zero latency: Real-time synchronization of BIM data in virtual reality for collaborative decision-making, Automation in Construction 85: 51–64. https://doi.org/10.1016/j.autcon.2017.10.009
Dünser, A.; Steinbügl, K.; Kaufmann, H.; Glück, J. 2006. Virtual and augmented reality as spatial ability training tools, in ACM International Conference Proceeding Series, 6–7 July 2006, Christchurch, New Zealand, 125–132. https://doi.org/10.1145/1152760.1152776
EIA. 2012. A look at the US building stock: results from EIA’s 2012 commercial buildings energy consumption. US Energy Information Administration [online], [cited 21 May 2017]. Available from Internet: http://www.eia.gov/consumption/commercial/reports/2012/buildingstock/
Ergan, S.; Yang, S. 2017. Visualization support for facility operations and maintenance, in D. Willis, W. Braham, K. Muramoto, D. Barber (Eds.). Energy accounts: Architectural representations of energy, climate and the future. New York: Routledge, 142–148.
Ergan, S.; Yang, X. 2015. Value of 3D gaming engine based virtual models in understanding behaviors of facility operators during FM, in CIB W78 Conference, 27–29 October 2015, Eindhoven, Netherlands.
Evans, F.; Skiena, S.; Varshney, A. 1996. Optimizing triangle strips for fast rendering, in IEEE Proceedings on Visualization, 28–29 October 1996, San Francisco, California, 319–326. https://doi.org/10.1109/VISUAL.1996.568125
Figueres-Munoz, A.; Merschbrock, C. 2015. Overcoming challenges in BIM and gaming integration: the case of a hospital project, WIT Transactions on the Built Environment 149: 329–340. https://doi.org/10.2495/BIM150281
Gallaher, M. P.; O’Connor, A.; Dettbarn, J. L.; Gilday, L. T. 2004. Cost analysis of inadequate interoperability in the US capital facilities industry. NIST Report 04-867, NIST Advanced Technology Program, Information Technology and Electronics Office, Gaithersburg, Maryland.
Germs, R.; Jansen, F. 2001. Geometric simplification for efficient occlusion culling in urban scenes, in Proceedings of WSCG, 5–9 February 2001, Plzen, Czech Republic.
Gopinath, R.; Messner, J. I. 2004. Applying immersive virtual facility prototyping in the AEC industry, in Proceedings of the Conference on Construction Applications of Virtual Reality (CONVR 2004), 14–15 September 2004, Lisbon, Portugal, 14–15.
Goulding, J. S.; Rahimian, F. P.; Wang, X. 2014. Virtual-reality based cloud BIM platform for integrated AEC projects, Journal of Information Technology in Construction 19: 308–325.
Hammad, A.; Wang, H.; Mudur, S. P. 2009. Distributed augmented reality for visualizing collaborative construction tasks, Journal of Computing in Civil Engineering 23(6): 418–427. https://doi.org/10.1061/(ASCE)0887-3801(2009)23:6(418)
Heydarian, A.; Pantazis, E.; Carneiro, J. P.; Gerber, D.; Becerik-Gerber, B. 2015. Towards understanding end-user lighting preferences in office spaces by using immersive VEs, in Proceedings of Computing in Civil Engineering, 21–23 June 2015, Austin, Texas, USA, 475–482. https://doi.org/10.1061/9780784479247.059
Hoppe, H. 1996. Progressive meshes, in ACM SIGGRAPH Proceedings, 1996, 99–108.
Johansson, M.; Roupé, M.; Tallgren, M. 2014. From BIM to VR – Integrating immersive visualizations in the current design process, in Proceedings of the 32nd eCAADe Conference, 10–12 September 2014, Newcastle upon Tyne, England, UK, 261–269.
Kang, J.; Ganapathi, A.; Nseir, H. 2012. Computer aided immersive VE for BIM, in The 14th International Conference on Computing in Civil and Building Engineering, 27–29 June 2012, Moscow, Russia.
Kasireddy, V.; Zou, Z.; Akinci, B.; Rosenberry, J. 2016. Evaluation and comparison of different virtual reality environments towards supporting tasks done on a virtual construction site, in Construction Research Congress 2016, 31 May – 2 June 2016, San Juan, Puerto Rico, 2371–2381. https://doi.org/10.1061/9780784479827.236
Kumar, S.; Hedrick, M.; Wiacek, C.; Messner, J. 2011. Developing an experienced-based design review application for healthcare facilities using a 3D game engine, Journal of Information Technology in Construction 16(6): 3–22.
Lee, S.; Akin, Ö. 2011. Augmented reality-based computational fieldwork support for equipment operations and maintenance, Automation in Construction 20(4): 338–352. https://doi.org/10.1016/j.autcon.2010.11.004
Lin, Y. C.; Su, Y. C. 2013. Developing mobile-and BIM-based integrated visual facility maintenance management system, The Scientific World Journal. Article ID 124249. https://doi.org/10.1155/2013/124249
Messner, J. 2006. Evaluating the use of immersive display media for construction planning, in Intelligent Computing in Engineering and Architecture. EG-ICE 2006. Lecture Notes in Computer Science, Vol. 4200. Springer, Berlin, Heidelberg, 484–491. https://doi.org/10.1007/11888598_43
Mozaffari, E.; Hammad, A.; El-Ammari, K. 2005. Virtual reality models for location-based facilities management systems, in The 1st CSCE Specialty Conference on Infrastructure Technologies, Management and Policy, 2–4 June 2005, Toronto, Canada, 132.1–132.10.
Nopachinda, S.; Ergan, S. 2016. Challenges in converting building information models into VEs for FM operations and user studies in the built environment, in The 16th International Conference on Computing in Civil and Building Engineering (ICCCBE 2016), 6–8 July 2016, Osaka, Japan, 758–765.
O’Connor, J.; Davis, V. 1988. Constructability improvement during field operations, Journal of Construction Engineering and Management 114(4): 548–564. https://doi.org/10.1061/(ASCE)0733-9364(1988)114:4(548)
Pitt, M.; Goyal, S.; Holt, P.; Ritchie, J.; Day, P.; Simmons, J.; Robinson, G.; Russell, G. 2005. An innovative approach to facilities management in the workplace design brief: Virtual reality in design, Facilities 23(7/8): 343–355. https://doi.org/10.1108/02632770510600290
Pulaski, M. H.; Horman, M. J.; Riley, D. R. 2006. Constructability practices to manage sustainable building knowledge, Journal of Architectural Engineering 12(2): 83–92. https://doi.org/10.1061/(ASCE)1076-0431(2006)12:2(83)
Regan, M.; Ronald, P. 1994. Priority rendering with a virtual reality address recalculation pipeline, in Proceedings of the 21st Annual Conference on Computer Graphics and Interactive Techniques, 24–25 July 1994, Orando, FL, USA, 155–162. https://doi.org/10.1145/192161.192192
Revit API. 2017. Detail level property representation for geometry extraction [online], [cited 21 May 2017]. Available from Internet: http://www.revitapidocs.com/2018/887c4c25-fe14-2633-b84c-09d2f1279c9e.htm
Saeidi, S.; Rizzuto, T.; Zhu, Y.; Kooima, R. 2015. Measuring the effectiveness of an immersive VE for the modeling and prediction of occupant behavior, in Proceedings of Sustainable Human-Building Ecosystems, 5–6 October 2015, Pittsburgh, Pennsylvania, USA, 159–167. https://doi.org/10.1061/9780784479681.017
Savioja, L.; Mantere, M.; Olli, I.; Äyräväinen, S.; Gröhn, M.; Iso-Aho, J. 2003. Utilizing VEs in construction projects, International Journal of IT in Construction 8: 85–99.
Selcuk, A.; Gudukbay, U.; Ozguc, B. 1998. A survey of interactive realistic walkthrough techniques in complex graphical environments, in Proceedings of the 13th International Symposium on Computer and Information Sciences, 26–28 October 1998, Antalya, Turkey.
Shen, Z.; Issa, R.; Gu, L. 2007. Semantic 3D CAD and its applications in construction industry – an outlook of construction data visualization, in Advances in Visual Information Systems. Lecture Notes in Computer Science, Vol. 4781. Springer Berlin / Heidelberg, 461–467. https://doi.org/10.1007/978-3-540-76414-4_45
Shen, Z.; Jiang, L.; Grosskopf, K.; Berryman, C. 2012. Creating 3D web-based game environment using BIM models for virtual on-site visiting of building HVAC systems, in Proceedings of Construction Research Congress, 21–23 May 2012, West Lafayette, Indiana, USA, 1212–1221. https://doi.org/10.1061/9780784412329.122
Shi, Y.; Du, J.; Lavy, S.; Zhao, D. 2016. A multiuser shared VE for facility management, Procedia Engineering 145: 120–127. https://doi.org/10.1016/j.proeng.2016.04.029
Stell, J.; Worboys, M. 1998. Stratified map spaces: A formal basis for multi-resolution spatial databases, in Proceedings of the 8th International Symposium on Spatial Data Handling, 11–15 July 1998, Vancouver, Canada, 180–189.
Unity Technologies. 2016. Optimizing graphics performance [online], [cited 15 April 2016]. Available from Internet: http://docs.unity3d.com/Manual/OptimizingGraphicsPerformance.html
Wang, X.; Dunston, P.; Skibniewski, M. 2004. Mixed reality technology applications in construction equipment operator training, in Proceedings of the 21st International Symposium on Automation and Robotics in Construction, 21–25 September 2004, Jeju, Korea. https://doi.org/10.22260/ISARC2004/0069
Wang, X.; Kim, M. J.; Love, P.; Kang, S. 2013. Augmented reality in built environment: classification and implications for future research, Automation in Construction 32: 1–13. https://doi.org/10.1016/j.autcon.2012.11.021
Woo, J.; Peterson, M. A.; Gleason, B. 2016. Developing a virtual campus model in an interactive game-engine environment for building energy benchmarking, Journal of Computing in Civil Engineering 30(5). https://doi.org/10.1061/(ASCE)CP.1943-5487.0000600
Yan, W.; Culp, C.; Graf, R. 2011. Integrating BIM and gaming for real-time interactive architectural visualization, Automation in Construction 20(4): 446–458. https://doi.org/10.1016/j.autcon.2010.11.013
Yang, S.; Ergan, S. 2014. Evaluation of visualization techniques for use by facility operators during monitoring tasks, Automation in Construction 44: 103–118. https://doi.org/10.1016/j.autcon.2014.03.023
Yang, S.; Ergan, S.; Knox, K. 2015. Requirements of integrated design teams while evaluating advanced energy retrofit design options in immersive VEs, Journal of Buildings 5(4): 1302–1320. https://doi.org/10.3390/buildings5041302
Yang, X.; Ergan, S. 2016. Leveraging BIM to provide automated support for efficient troubleshooting of HVAC related problems, Journal of Computing in Civil Engineering 30(2): 04015023.1-10. https://doi.org/10.1061/(ASCE)CP.1943-5487.0000492
Yerrapathruni, S. 2003. Using 4D CAD and immersive VEs to improve construction planning: MS thesis. The Pennsylvania State University, Pennsylvania.
Zhang, H. 1998. Effective occlusion culling for the interactive display of arbitrary models: PhD Dissertation. University of North Carolina, Chapel Hill.
Behzadan, A. H.; Timm, B. W.; Kamat, V. R. 2008. General-purpose modular hardware and software framework for mobile outdoor augmented reality applications in engineering, Advanced Engineering Informatics 22: 90–105. https://doi.org/10.1016/j.aei.2007.08.005
Bern, M.; Eppstein, M. 1992. Mesh generation and optimal triangulation, Computing in Euclidean Geometry 1: 23–90. https://doi.org/10.1142/9789814355858_0002
Bille, R.; Smith, S.; Maund, S.; Brewer, G. 2014. Extending building information models into game engines, in Proceedings of the 2014 Conference on Interactive Environment, 2–3 December 2014, Newcastle, NSW, Australia, 1–8. https://doi.org/10.1145/2677758.2677764
Billger, M.; Heldal, I.; Stahre, B.; Renstrom, K. 2004. Perception of color and space in VR: a comparison between a real room and virtual reality models, in Proceedings of SPIE – The International Society for Optical Engineering, 2–3 August 2004, Denver, CO., USA.
Bowman, D.; Ray, A.; Gutierrez, M.; Mauldon, M.; Dove, J.; Westman, E.; Setareh, M. 2006. Engineering in three dimensions: Immersive VEs, interactivity, and 3D user interfaces for engineering applications, in Proceedings of GeoCongress, 26 February –1 March 2006, Atlanta, Georgia, 1–17.
Chen, H. M.; Hou, C. C.; Wang, Y. H. 2013. A 3D visualized expert system for maintenance and management of existing building facilities using reliability-based method, Expert Systems with Applications 40(1): 287–299. https://doi.org/10.1016/j.eswa.2012.07.045
Chen, J. C.; Thropp, J. E. 2007. Review of low frame rate effects on human performance, IEEE Transactions on Systems, Man and Cybernetics, Part A: Systems and Humans 37(6): 1063–1076. https://doi.org/10.1109/TSMCA.2007.904779
CIC. 2014. Computer integrated construction research group- workflow of exporting Revit models to Unity. Penn State CIC Research Group.
Dalton, B.; Parfitt, M. 2013. Immersive visualization of building information models. Design Innovation Research Center Working Paper 6 [1.0]. Reading: Design Innovation Research Centre, University of Reading.
Du, J.; Shi, Y.; Zou, Z.; Zhao, D. 2017a. CoVR: Cloud-based multiuser virtual reality headset system for project communication of remote users, Journal of Construction Engineering and Management 144(2): 04017109. https://doi.org/10.1061/(ASCE)CO.1943-7862.0001426
Du, J.; Zou, Z.; Shi, Y.; Zhao, D. 2017b. Simultaneous data exchange between BIM and VR for collaborative decision making, in ASCE International Workshop on Computing in Civil Engineering 2017, 25–27 June 2017, Seattle, Washington, USA, 1–8. https://doi.org/10.1061/9780784480830.001
Du, J.; Zou, Z.; Shi, Y.; Zhao, D. 2018. Zero latency: Real-time synchronization of BIM data in virtual reality for collaborative decision-making, Automation in Construction 85: 51–64. https://doi.org/10.1016/j.autcon.2017.10.009
Dünser, A.; Steinbügl, K.; Kaufmann, H.; Glück, J. 2006. Virtual and augmented reality as spatial ability training tools, in ACM International Conference Proceeding Series, 6–7 July 2006, Christchurch, New Zealand, 125–132. https://doi.org/10.1145/1152760.1152776
EIA. 2012. A look at the US building stock: results from EIA’s 2012 commercial buildings energy consumption. US Energy Information Administration [online], [cited 21 May 2017]. Available from Internet: http://www.eia.gov/consumption/commercial/reports/2012/buildingstock/
Ergan, S.; Yang, S. 2017. Visualization support for facility operations and maintenance, in D. Willis, W. Braham, K. Muramoto, D. Barber (Eds.). Energy accounts: Architectural representations of energy, climate and the future. New York: Routledge, 142–148.
Ergan, S.; Yang, X. 2015. Value of 3D gaming engine based virtual models in understanding behaviors of facility operators during FM, in CIB W78 Conference, 27–29 October 2015, Eindhoven, Netherlands.
Evans, F.; Skiena, S.; Varshney, A. 1996. Optimizing triangle strips for fast rendering, in IEEE Proceedings on Visualization, 28–29 October 1996, San Francisco, California, 319–326. https://doi.org/10.1109/VISUAL.1996.568125
Figueres-Munoz, A.; Merschbrock, C. 2015. Overcoming challenges in BIM and gaming integration: the case of a hospital project, WIT Transactions on the Built Environment 149: 329–340. https://doi.org/10.2495/BIM150281
Gallaher, M. P.; O’Connor, A.; Dettbarn, J. L.; Gilday, L. T. 2004. Cost analysis of inadequate interoperability in the US capital facilities industry. NIST Report 04-867, NIST Advanced Technology Program, Information Technology and Electronics Office, Gaithersburg, Maryland.
Germs, R.; Jansen, F. 2001. Geometric simplification for efficient occlusion culling in urban scenes, in Proceedings of WSCG, 5–9 February 2001, Plzen, Czech Republic.
Gopinath, R.; Messner, J. I. 2004. Applying immersive virtual facility prototyping in the AEC industry, in Proceedings of the Conference on Construction Applications of Virtual Reality (CONVR 2004), 14–15 September 2004, Lisbon, Portugal, 14–15.
Goulding, J. S.; Rahimian, F. P.; Wang, X. 2014. Virtual-reality based cloud BIM platform for integrated AEC projects, Journal of Information Technology in Construction 19: 308–325.
Hammad, A.; Wang, H.; Mudur, S. P. 2009. Distributed augmented reality for visualizing collaborative construction tasks, Journal of Computing in Civil Engineering 23(6): 418–427. https://doi.org/10.1061/(ASCE)0887-3801(2009)23:6(418)
Heydarian, A.; Pantazis, E.; Carneiro, J. P.; Gerber, D.; Becerik-Gerber, B. 2015. Towards understanding end-user lighting preferences in office spaces by using immersive VEs, in Proceedings of Computing in Civil Engineering, 21–23 June 2015, Austin, Texas, USA, 475–482. https://doi.org/10.1061/9780784479247.059
Hoppe, H. 1996. Progressive meshes, in ACM SIGGRAPH Proceedings, 1996, 99–108.
Johansson, M.; Roupé, M.; Tallgren, M. 2014. From BIM to VR – Integrating immersive visualizations in the current design process, in Proceedings of the 32nd eCAADe Conference, 10–12 September 2014, Newcastle upon Tyne, England, UK, 261–269.
Kang, J.; Ganapathi, A.; Nseir, H. 2012. Computer aided immersive VE for BIM, in The 14th International Conference on Computing in Civil and Building Engineering, 27–29 June 2012, Moscow, Russia.
Kasireddy, V.; Zou, Z.; Akinci, B.; Rosenberry, J. 2016. Evaluation and comparison of different virtual reality environments towards supporting tasks done on a virtual construction site, in Construction Research Congress 2016, 31 May – 2 June 2016, San Juan, Puerto Rico, 2371–2381. https://doi.org/10.1061/9780784479827.236
Kumar, S.; Hedrick, M.; Wiacek, C.; Messner, J. 2011. Developing an experienced-based design review application for healthcare facilities using a 3D game engine, Journal of Information Technology in Construction 16(6): 3–22.
Lee, S.; Akin, Ö. 2011. Augmented reality-based computational fieldwork support for equipment operations and maintenance, Automation in Construction 20(4): 338–352. https://doi.org/10.1016/j.autcon.2010.11.004
Lin, Y. C.; Su, Y. C. 2013. Developing mobile-and BIM-based integrated visual facility maintenance management system, The Scientific World Journal. Article ID 124249. https://doi.org/10.1155/2013/124249
Messner, J. 2006. Evaluating the use of immersive display media for construction planning, in Intelligent Computing in Engineering and Architecture. EG-ICE 2006. Lecture Notes in Computer Science, Vol. 4200. Springer, Berlin, Heidelberg, 484–491. https://doi.org/10.1007/11888598_43
Mozaffari, E.; Hammad, A.; El-Ammari, K. 2005. Virtual reality models for location-based facilities management systems, in The 1st CSCE Specialty Conference on Infrastructure Technologies, Management and Policy, 2–4 June 2005, Toronto, Canada, 132.1–132.10.
Nopachinda, S.; Ergan, S. 2016. Challenges in converting building information models into VEs for FM operations and user studies in the built environment, in The 16th International Conference on Computing in Civil and Building Engineering (ICCCBE 2016), 6–8 July 2016, Osaka, Japan, 758–765.
O’Connor, J.; Davis, V. 1988. Constructability improvement during field operations, Journal of Construction Engineering and Management 114(4): 548–564. https://doi.org/10.1061/(ASCE)0733-9364(1988)114:4(548)
Pitt, M.; Goyal, S.; Holt, P.; Ritchie, J.; Day, P.; Simmons, J.; Robinson, G.; Russell, G. 2005. An innovative approach to facilities management in the workplace design brief: Virtual reality in design, Facilities 23(7/8): 343–355. https://doi.org/10.1108/02632770510600290
Pulaski, M. H.; Horman, M. J.; Riley, D. R. 2006. Constructability practices to manage sustainable building knowledge, Journal of Architectural Engineering 12(2): 83–92. https://doi.org/10.1061/(ASCE)1076-0431(2006)12:2(83)
Regan, M.; Ronald, P. 1994. Priority rendering with a virtual reality address recalculation pipeline, in Proceedings of the 21st Annual Conference on Computer Graphics and Interactive Techniques, 24–25 July 1994, Orando, FL, USA, 155–162. https://doi.org/10.1145/192161.192192
Revit API. 2017. Detail level property representation for geometry extraction [online], [cited 21 May 2017]. Available from Internet: http://www.revitapidocs.com/2018/887c4c25-fe14-2633-b84c-09d2f1279c9e.htm
Saeidi, S.; Rizzuto, T.; Zhu, Y.; Kooima, R. 2015. Measuring the effectiveness of an immersive VE for the modeling and prediction of occupant behavior, in Proceedings of Sustainable Human-Building Ecosystems, 5–6 October 2015, Pittsburgh, Pennsylvania, USA, 159–167. https://doi.org/10.1061/9780784479681.017
Savioja, L.; Mantere, M.; Olli, I.; Äyräväinen, S.; Gröhn, M.; Iso-Aho, J. 2003. Utilizing VEs in construction projects, International Journal of IT in Construction 8: 85–99.
Selcuk, A.; Gudukbay, U.; Ozguc, B. 1998. A survey of interactive realistic walkthrough techniques in complex graphical environments, in Proceedings of the 13th International Symposium on Computer and Information Sciences, 26–28 October 1998, Antalya, Turkey.
Shen, Z.; Issa, R.; Gu, L. 2007. Semantic 3D CAD and its applications in construction industry – an outlook of construction data visualization, in Advances in Visual Information Systems. Lecture Notes in Computer Science, Vol. 4781. Springer Berlin / Heidelberg, 461–467. https://doi.org/10.1007/978-3-540-76414-4_45
Shen, Z.; Jiang, L.; Grosskopf, K.; Berryman, C. 2012. Creating 3D web-based game environment using BIM models for virtual on-site visiting of building HVAC systems, in Proceedings of Construction Research Congress, 21–23 May 2012, West Lafayette, Indiana, USA, 1212–1221. https://doi.org/10.1061/9780784412329.122
Shi, Y.; Du, J.; Lavy, S.; Zhao, D. 2016. A multiuser shared VE for facility management, Procedia Engineering 145: 120–127. https://doi.org/10.1016/j.proeng.2016.04.029
Stell, J.; Worboys, M. 1998. Stratified map spaces: A formal basis for multi-resolution spatial databases, in Proceedings of the 8th International Symposium on Spatial Data Handling, 11–15 July 1998, Vancouver, Canada, 180–189.
Unity Technologies. 2016. Optimizing graphics performance [online], [cited 15 April 2016]. Available from Internet: http://docs.unity3d.com/Manual/OptimizingGraphicsPerformance.html
Wang, X.; Dunston, P.; Skibniewski, M. 2004. Mixed reality technology applications in construction equipment operator training, in Proceedings of the 21st International Symposium on Automation and Robotics in Construction, 21–25 September 2004, Jeju, Korea. https://doi.org/10.22260/ISARC2004/0069
Wang, X.; Kim, M. J.; Love, P.; Kang, S. 2013. Augmented reality in built environment: classification and implications for future research, Automation in Construction 32: 1–13. https://doi.org/10.1016/j.autcon.2012.11.021
Woo, J.; Peterson, M. A.; Gleason, B. 2016. Developing a virtual campus model in an interactive game-engine environment for building energy benchmarking, Journal of Computing in Civil Engineering 30(5). https://doi.org/10.1061/(ASCE)CP.1943-5487.0000600
Yan, W.; Culp, C.; Graf, R. 2011. Integrating BIM and gaming for real-time interactive architectural visualization, Automation in Construction 20(4): 446–458. https://doi.org/10.1016/j.autcon.2010.11.013
Yang, S.; Ergan, S. 2014. Evaluation of visualization techniques for use by facility operators during monitoring tasks, Automation in Construction 44: 103–118. https://doi.org/10.1016/j.autcon.2014.03.023
Yang, S.; Ergan, S.; Knox, K. 2015. Requirements of integrated design teams while evaluating advanced energy retrofit design options in immersive VEs, Journal of Buildings 5(4): 1302–1320. https://doi.org/10.3390/buildings5041302
Yang, X.; Ergan, S. 2016. Leveraging BIM to provide automated support for efficient troubleshooting of HVAC related problems, Journal of Computing in Civil Engineering 30(2): 04015023.1-10. https://doi.org/10.1061/(ASCE)CP.1943-5487.0000492
Yerrapathruni, S. 2003. Using 4D CAD and immersive VEs to improve construction planning: MS thesis. The Pennsylvania State University, Pennsylvania.
Zhang, H. 1998. Effective occlusion culling for the interactive display of arbitrary models: PhD Dissertation. University of North Carolina, Chapel Hill.