Part of working in a BIM environment is putting together all of the little pieces that you know and turning it into a useful workflow. Do you have a 3D file, such as an FBX, that has some camera views saved in it, and you would like to convert these to BCF, perhaps for eventual import to Revit or some other application?
Navisworks can help here. It is pretty smart when it comes to most 3D formats. Importing an FBX will bring in camera views as Saved Viewpoints. If you have an FBX file from 123D Catch, it will contain Camera views that match the actual camera locations. Here’s what to do:
Firstly, make sure you have a model on Glue that you can access. Did you know that when you Glue something from Navisworks, it makes an NWD and puts it in a folder like this: “C:UsersLuke JohnsonAppDataLocalNavisworksPlugin63baac4b-76c8-4ff8-9039-d51645fd1ddc.nwd”
Once you have a model on Glue that you would like to download and use as modelling context in Revit, make a new Navisworks file and:
Append that model back to Navisworks from Glue (it will look like you opened an NWD, with Clashes, Search Sets and Viewpoints all appearing. This tells us that BIM 360 Glue stores all that information in the cloud, at least when the model “originated” in Navisworks.)
Make a new Revit file. I had problems using the Construction template – it seemed to break the coordinates somehow… In any case, when I just used “None” template, it worked fine.
Link the DWG into Revit, Origin to Origin
Do your Revit modelling (in the screenshots below, I modelled part of a roof)
Glue the new roof directly from Revit (you may want to Hide the DWG file prior to Appending). This will create a new Model. On BIM 360 Glue, you now have the original model plus this new model from Revit.
Go to Glue app in Windows and make a new Merged Model. Tick the boxes for the original model, and this new model from Revit.
Back in Navisworks, we can either choose to Append the entire new merged model, or just the new “piece” that we modelled in Revit.
I have previously discussed going from Navisworks to Revit using FBX – 3dsMax – SAT. However, maybe we can do this without 3dsMax. Did you know that vanilla AutoCAD has a FBXIMPORT command?
1) Export FBX from Navisworks – it will ignore Section clipping planes, but it will respect the Hide/Required setting of the view. You can limit polygons (advised for big models)
2) FBXIMPORT in AutoCAD – untick Cameras and Block options as they can be problematic. Then save DWG. (Note – see below for correct 1:304.8 import scale) EDIT: If using Navisworks 2015 FBX export to version 2014, with Advanced Options units set to millimeters, you can import to AutoCAD 2015 with 1:1 scale factor (using latest service packs)
3) Open Revit and Link in the DWG. For this example, I used Origin to Origin as I wanted to try round-tripping back to Navisworks.
Once I exported the NWC and put it back into Revit, I noticed the file was out of scale. Now, I experimented with a few different scale settings, but everytime it was a scale of about 30 or 300 wrong. 1 foot = exactly 304.8 mm. Evidently, the “internal” units of an FBX are feet. So, when we import to AutoCAD we need to use this setting to translate to mm:
This time, when I exported the Revit view to a NWC, and then appended it back to Navisworks – it can came back in exactly the right place. This workflow relies on using the internal Revit Zero point and Origin to Origin linking.
There you go – now you can roundtrip any mesh geometry from Navisworks to AutoCAD to Revit and back to Navisworks 🙂
What’s so good about FBX? Geometry, materials, lights and camera assets are all contained in the file. It also supports animation.
What formats can FBX Review handle? .fbx, .3ds, .obj, .dxf, .dae, .bvh, .htr, .trc, .asf, .amc, .c3d, .aoa, .mcd.
From the App description: Features * Import and review 3D files without using full commercial 3D animation software. * DirectX 11 enabled viewport for high-fidelity asset review. * Toggle shading modes, animations, cameras, and scene lights. * Familiar and intuitive playback controls to review animations. * Formats supported: .fbx, .3ds, .obj, .dxf, .dae, .bvh, .htr, .trc, .asf, .amc, .c3d, .aoa, .mcd.
Transfer files from one file format to another quickly and easily with the FBX Converter. This utility enables you to convert OBJ, DXF™, DAE, and 3DS files to or from multiple versions of the FBX format. New tools are now available with the FBX Converter 2012.1. You can view FBX animation files in real time with the FBX Viewer, explore and compare FBX file contents with the FBX Explorer, and manage animation takes with the FBX Take Manager.
Here is a quick video of me converting a OBJ to FBX using the above tool. In the video I also use the FBXIMPORT command to bring the FBX into AutoCAD. From there, you could save as DWG and bring into Revit:
PS – This still doesn’t quite solve the Mesh to Solid conversion problem … I am currently experimenting with MESHSMOOTH and CONVTOSOLID.
EDIT: Here is a vid showing Revit to 3dsMax via FBX.