The 3D City Model has been a long time coming, It is not new, rather, it has evolved over time through a process of research and innovation that includes applications, concepts and technology. As these became more mature, they integrated more closely. Adding digital computation into the mix placed 3D into the mainstream of internet use and simply pushed 3D city models out into the great wide open of interested users.
3D city models are at the early stages of innovation. The integration of 3D technology, applications and concepts have placed them into wider awareness, and into a more useable focus. Today, anyone can click on a link and 3D city model-like content will flow directly to the user. This is important to realize because only a few short years ago, almost all city modeling presentations were oriented around 2D visualization. The public and business have grown accustomed to this higher level of 'reality' representation as compared to 2D. Furthermore, real-world imaging from satellite down to UAV is providing accurate and high-resolution imaging that is coupled to these representations.
3D Concept: Many people are now aware that 'going digital' is the driving conceptual force that is propelling 3D city modeling forward. Most conference participants will hear one or more speakers talk about digital society, moving data to digital or something like that. They are referring to the fact that the business models of the future (ie BIM, 3D cities) will depend upon digital data and are likely to originate in the Cloud. Going digital means moving away from paper. It also means more collaboration and sharing of data.
Another important rising concept is the use and application of spatial analytics in 3D city modeling. On the CAD side of the equation, infrastructure objects and scheduling become searchable and analytical in scope. Concepts like thermal heating and cooling are becoming more popular and energy use is a topical subject being implemented in some tools.
3D Applications: As 3D data from both lidar and photogrammetry sources are able to provide digital information useful for 3D city modeling, the types of applications that can be developed is expanding. Whereas most were content to simply show 3D buildings, advances in applications are coupling sociological, transportation habits, road conditions and so on into the digital data stream alongside 3D models. This is giving rise to new business models and solving problems we sometimes simply cannot fully appreciate because they are so new and available for the first time.
3D Technology: Neither photogrammetry or Lidar are new. The first being around for over 100 years, while Lidar has been present for decades. Even 3D printing is not new and has been over a decade in the market. So what changed? Why are people so enamoured with 3D city models today?
This largely revolves around the innovation leading to the ability to swiftly being able to extract 3D content and being able to integrate it into a useable manner for 3D modeling. Most photogrammetry led to 2D maps (ie. forestry, planimetric maps), but only recently has automated feature analysis been possible, allowing for large quantities of aerial images to become quickly useable. On the Lidar side, everyone is aware of the nice, colorful 3D images that these technologies generate in vector point clouds. Again, extracting (processing) these point clouds into useable forms is still relatively new. Key to this has been the ability to geo-reference them quickly and accurately.
While criminals are probably smacking their lips with the hungry possibilities of laser scanners worth several tens of thousands of Euro sitting atop cars in dark alleys, the future is likely to give way to lower cost Lidar worth only a few hundred Euro as rising competition hits the market. The same can be said for 3D city modeling Cloud-based services too. In addition, we are likely to see more wearable technologies in the future that will be integrated into 3D city models.
The rise of 3D city models is an evolutionary success. We can track these technologies and applications over time indpendently. But the real interesting story, and benefits are only now beginning to be seen and ... further imagined.