Question about Revit-to-MAX and Xrefs

[pfschuyler]

I have a Revit site model with a number of identical building instances, rotated and positioned on a Revit site model. I want to bring this site model and its building instances into 3dsMAX and render (:-P). I would like things to work out exactly like they are working in Revit. I would like the ability to edit 1 instance of the building and enhance its materials or geometry, then have those changes immediately translated to all of the other identical building instances.

Is there a way to do that through this DWG translator/linking process, to accomodate instances?

I have also noticed some disturbing things, if I export a DWG file of the whole thing (site + buildings) from Revit, the mapping coordinates for all of the building objects appear to be aligned to the master site model WCS, and not to the individual objects. So for example the mapping coodinates of a roof on a building that is rotated will be completely skewed with respect to the roof object itself and instead will be oriented along the XYZ of the site. Is there a setting that can override this?

The only way I can think of to do what I want is to link the isolated building DWG to a separate MAX scene, perform my material and geometry additions there, then x-ref in a 3dsMAX scene that contains only the linked site model. From there I could make instances of my building geometry, rotating and positioning the individual buildings. Of course that is a ton of unecessary, repeat work. But I don't know another way to do it.

Any ideas? Thanks.

Paul Schuyler

[pfschuyler]

To answer my own question I've come up with a pretty satisfying process. Its a bit time consuming to set up, but it works great for Revit models and instancing.

1. In Revit I open the site model in a 3d view and turn off all of the imported Revit building instances, leaving only the site elements visible. I export that DWG which contains only the site elements. In 3dsMAX, I link this DWG site model, and save this as a separate site-model-only 3dsMAX scene.
2. In Revit, I open up the building model by itself, and export that to DWG. I link that DWG to a new 3dsMAX file, and from there I can add lots of detail, geometry, materials, lights, etc. This becomes my building-only 3dsMAX scene.
3. I open my site-only 3dsMAX scene and Xref in my building-only 3dsMAX scene. I then bind this to an object that I can move around. Doing this I can reposition the Xref back into the correct positions on the site, one at a time.
4. I repeat step 3 as many times as needed within the site model, to add more building instances. The cool thing is that I can reference my building-only 3dsMAX scene 20 times, and my file size stays about the same size as it was (basically only the site elements). Everything is interactive and you can't screw up the building model, because you can't select it. My materials are totally instanced, so if I change anything on the building model that gets propagated to all of the building instances. And especially satisfying is that the mapping coordinates for the building are for the most part correct, as taken from the original building DWG model they are lined up correctly.

I thought this would be a killer workflow with all this repositioning to be done, but its actually not bad at all. Working only with the building model gives me space to tweak the materials without a lot of geometry overhead. Likewise if more modeling is needed, it is much easier to do that in the building-only model, or site-only model. Xrefing and positioning the building instances within the 3dsMAX site model is fast and easy, and the Xref scene features allow for separate control of lights, cameras, etc. Somehow this workflow just works, I'm happy because it allows everything to flow reasonably without a lot of hardware problems. Too bad you can't do this automatically from Revit. If you try to do it all from Revit via DWG export (and link that into MAX), you will hate life!

I realize that this is not advanced for some of you out there, but this can take a lot of the pain out of the process for someone getting started with Revit and MAX and the DWG/linking workflow.

Paul Schuyler