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Table 1 Three-dimensional data formats

From: Qualitative study of the incompatibility of indoor map file formats with location software applications

 3D DATA MODELS
IFCCityGML v2IndoorGMLLAS
Primary PurposeIFC is used to describe building and construction industry data. It facilitates interoperability among the architecture, engineering and construction industries.CityGML is an application schema for Geography Markup Language v3.1.1. CityGML is used to reach a common definition of elements in a 3D city model.Indoor GML is used to represent and allow for exchange of geoinformation requred to build and operate indoor navigation systems.LAS is the standard file type for point clouds data.
Supporting OrganizationBuildingSMARTOpen Geospatial Consortium (OGC)Open Geospatial Consortium (OGC)American Society for Photogrammetry and Remote Sensing (ASPRS)
Example of Software for ViewingRevit for creating IFC filesCityGML SpiderViewer, QGIS, ArcGISFMEGIS or photogrammetry software i.e. ESRI or LAS Tools
Description of GeometryEach object such as wall, floor, window, door is associated with property ‘IFCSHAPEREPRESENTATION,’ which contains the object’s geometry.The geometry is represented in 5 levels of details (LOD0 - LOD4)The geometry may be defined either by external reference, where the object is defined in another dataset (CityGML or IFC for example) and referenced in the IndoorGML file, or by explicit definition of space cell geometry as either a 3D solid or a 2D surface.LAS files store data in tuples of x, y and z data with each tuple representing a point in space. The combination of many tuples in close proximity can create a 3D representation.
Representation of Object LocationMultiple local spatial reference systems (SRS) can be defined for a file. The information to convert file into a real world spatial reference systems is included within the file.An SRS is defined for the file and all the objects that use that reference system unless overruled by defining a local SRS for that particular object or a set of objects.An SRS is defined and the information to convert to a real world reference system is included in the file.An SRS for the points is defined in the file.