3d bag project

BIM/GIS

The BAG3D is a dataset offered that is generated and maintained by the TUdelft. In this dataset one can find the geometry of the buildings of the Netherlands at volume study level. This dataset is, simply put, generated on the basis of the point data from the AHN (Algemeen Hoogtebestand Nederland), where by extrapolating the point data, the geometry is generated. The Digital Discovery Lab looked at ways in which the data can be made available as ‘native’ geometry in Revit. This looked at both the usability of the CityJson format and the OBJ format. With the help of the visual script program Dynamo, both file formats were compared with each other with the aim of using the dataset as optimally as possible in Revit. The starting point for this research was therefore to make the geometry available as much as possible in lod2.2 where the metadata can be added as parameters to the various objects. The challenges we have encountered are explained further on this page.

What do you want to use the data for?

Visualize

The geometry of the BAG3D, if usable in Revit, can be well used for creating visualizations. It is important that the materials of the geometry can be changed. This has therefore been established as the starting point for this research.

Analyze

The data from the BAG3D can, if usable in Revit, be used to perform (urban) Analyses. These analyses can then be performed in Revit (e.g. filter, schedules, etc.) or in external programs such as Dynamo (Visual Scripting) of Grasshopper (Visual Scripting). It is important that the buildings are imported as separate families and that the metadata is added. In this way, you can also link other datasets to the objects and retrieve the objects separately from each other within other software.

Communicate

In the BIM world, communication is often done through the IFC format. It is therefore also important that the objects can be exported individually as ifc objects. This makes it possible to communicate through the objects. This was an important starting point for this research.

Generate

Based on the geometry from the BAG3D, it can be useful to generate new geometry again. We have stated that it could therefore be useful if you could also adjust the geometry.

Findings and results

The findings of this study can be found in the PowerPoint presentation in the knowledgebase. In addition to this powerpoint presentation
you can also download the created scripts so that you can see for yourself how it works
ans how it shaped itself.