Creating Files for Offline BIM

See also:

• Viewing BIM Models Offline - loading BIM models from the file system
• Viewing Models from BIMServer - loading IFC models from BIMServer

Introduction

In this quick tutorial you'll learn how to download model metadata from BIMServer, for use when viewing BIM models offline with xeokit.

Contents

• Creating a glTF Model
  • 1. Download an IFC File
  • 2. Install Pipeline Tools
  • 3. Convert IFC to COLLADA
  • 4. Convert COLLADA to glTF
• Creating JSON IFC Metadata
  • 1. Install BIMServer
  • 2. Upload IFC to BIMServer
  • 3. Install and run xeokit-bimserver-utils
• Conclusion

Creating a glTF Model

1. Download an IFC File

We'll use IFC models from the Schependomlaan dataset.

2. Install Pipeline Tools

We'll use these CLI tools to transform IFC into glTF:

• ifcConvert to convert IFC files to DAE
• COLLADA2GLTF to convert DAE to glTF

We'll assume that these are installed relative to the current working directory.

3. Convert IFC to COLLADA

Convert the Schependomlaan IFC STEP file into a COLLADA file:

./IfcConvert --use-element-guids schependomlaan.ifc  schependomlaan.dae

4. Convert COLLADA to glTF

Then convert the COLLADA into a single glTF 2.0 text file with embeddded geometry:

./COLLADA2GLTF/build/COLLADA2GLTF-bin -i schependomlaan.dae -o schependomlaan.gltf

Creating JSON IFC Metadata

1. Install BIMServer

Download and install BIMServer v1.5.120 - the standalone JAR version is easiest.

Note the admin login credientials.

2. Upload IFC to BIMServer

Create a project in BIMServer and check in the IFC file.

Note the project ID.

3. Install and run xeokit-bimserver-utils

Download and install xeokit-bimserver-utils.

Tweak the configurations within that util as described in the README.md. You'll need to configure it with your project ID and login credentials that have permission to read the project (just use admin, it's easier than creating and authorizing a new user via the BIMServer API).

Run the utility, which will write out a file of JSON metadata for the confgured model.

Conclusion

Now we have a glTF file with an accompanying JSON file that specifies metadata for it. We can now load a BIM model from those two files as described in Viewing BIM Models Offline.