We’re currently developing our Revit to UE4 workflow are having a some decent success. It’s not simple by any means, but we are able to reuse the geometry, generate collision hulls, and light map UV’s on the fly. We do take everything through Max right now and making regular UV’s are definitely the bottle neck at the moment. You also have to watch out for smoothing groups, most stuff out of Revit does not had any smoothing group information, which may or may not cause a problem when the asset gets to unreal. We also create materials in UE4, discarding the revit materials, in fact they are only used for assignment. Be sure to convert them to standard materials. Also, take a look at tom shannon’s maxscript, it’s a huge time saver. TS_Tools v1.1: UE4 Mass FBX Exporter v1.1 and UCX Namer v1.0
Sounds like a lot of work, but it’s not too bad. The speed and visual fidelity in which you work in Unreal makes it very attractive. The ability to work on visuals, render animations, add interactivity, etc, al in real time, is frankly amazing.
Going foward, we are looking at automating much of the conversion process: Taking all the meshes from revit (via FBX or IFC), finding duplicates/instances (think of all the CW mullions), maybe remove unneeded polys, then recording their locations in 3d space, then running a placement script in UE after working on and importing the representative meshes.
My tests have been quite small at the moment, but we’ve got revit models for every project we do, and I’m pushing for Unreal to become part of our design viz pipeline.