Galdos Systems, as one of the original creators of the standard, has a long-standing history with GML schemas and data. Based on the Geography Markup Language (GML) standard, CityGML is becoming a de-facto standard for representating and exchanging 3D city models. CityGML captures topographic objects in cities and regional models in terms of their appearance, but also with respect to their geometric, topological, and semantic properties.
Three-Dimensional City Models
CityGML is a rich standard for creating three-dimensional models of cities. The data has inherent topology, geometry, and semantics so it can be parsed in ways that have meaning when visualized in a viewer application. The concept of one object being inside another, or being part of another, can be translated into a virtual view that can be navigated from any direction and explored inside and out.
Galdos developed INspector™ as one such viewer. INspector provides a number of specialized views that take full advantage of the depth of CityGML data models by presenting a complete 360 degree view of the model that can be panned and zoomed, and which shows the interior structure and contents of the modeled buildings.
Galdos combines 3D city models with photographic data to create virtual reality models of cities. By backing the mogel with an INdicio Registry that associates each building in the model with additional metadata, the resulting landscape can display any relevant data about a building with just a click of the mouse. This has extensive implications for managing intelligent cities and all the artefacts necessary to plan, build, and maintain them.
CityGML provides a rich information model for representing urban objects because it represents not only the buildings, bridges, and tunnels, but also the surrounding terrain, transportation facilities, vegetation, water bodies, and so on that the buildings exist within. CityGML supports semantic and thematic data, as well as taxonomies, and the five levels of detail allow zooming from far out (looking at a whole city or at the outside walls of a building) to close in (checking out the cabinets in the kitchen and the beams holding the roof up).
Galdos Systems is engaged in long-term projects with several municipalities to develop CityGML databases that will support the ongoing management and development of their related urban areas. These projects include maintaining shared base maps of roads, land parcels, and buildings, as well as managing utilities and infrastructure development.