preparing revit files for import

[philvanderloo]

Does anyone have a good checklist they wouldn't mind sharing for how you optimize your Revit files for import to 3ds Max?

Thank You

[Chris MacDonald]

let me know how you get on with your quest for the holy grail there!

[philvanderloo]

Ya, I figure if I keep turning over stones, sooner or later I'm bound to come up with something,.......

[Scott Schroeder]

Create a separate camera that is only used for Max export. Hide all of the useless crap that you'll never render so you don't bog down your export process. Items such as furniture, casework, light fixtures, landscape, etc. In the end, you really only should have the core shell of the building and any major objects that you will see.

 

You can export out it all as one FBX, EXCEPT the curved surfaces like railings and the such. Do not export those with this FBX. Instead, create a separate camera view and hide everything except curved surfaces. Export this one as a DWG and set the solids to ACIS. This way, the curved surfaces will export into max like you would expect them to be modeled. Not a mess of 6 bajillion vertex points.

 

I would advise against a direct link to Revit and instead direct link to the FBX and the DWG file. Why you ask? Well, it's slower doing the direct link to the Revit file since Revit still has to open, you still have to export an FBX, and you still have to link it into Max. But this is all just done under the hood instead. So rather than deal with that mess, just skip the process and do a direct link to the FBX and DWG file. If you want, you can always bind them later on, but you get way more intuitive options when linking versus just directly importing. I usually set it to combine by category since we rarely have materials in our Revit files. I also set it to not import lights as you don't want Revit lights in a Vray scene. Bad things happen.

 

The big one is make sure you are creating objects correctly in Revit. You can't fix a crappy model during the export process. So if your Revit file is junk to begin with, then it's junk you'll end up with in Max.

Edited March 2, 2015 by VelvetElvis

[Devin Johnston]

Scott my firm is transitioning from ArchiCAD to Revit over the next 2 years and I'm going to have to deal with this. How slow is the Revit linking, are we talking seconds or minutes?

[Scott Schroeder]

Well, apparently it is much much faster with Max 2015 Extension 2 to do direct Revit links. However, you still get the screwed up curved surfaces that are solved by doing the DWG route. Yet, FBX gives you more intuitive "combine by" options. Oh if Autodesk could only do a DWBX format.

 

It depends on the file and how it's stored. With one of our massive athletic campus master plans that's stored on the Revit server, it takes about 2-3 hours to link. Which is beyond stupid and why we've ditched the whole direct to revit linking idea. For an average project, again depending on how much stuff you have like curtain wall, you are looking at 5-10 minutes for direct link to Revit. For the direct to FBX/DWG link you are looking at on average 30-60 seconds to export from Revit and 1-3 minutes to import into Max.

 

I like to cap things at if it takes longer than 5 minutes to do either import or export, then something isn't optimized somewhere.

[Devin Johnston]

Oh man this is going to suck I can already tell.

[Scott Schroeder]

It can be painful. A lot of what makes it easier is communication between the revit team and us as modelers. The nice thing is you are starting from scratch and you aren't trying to cram in the export process into an already existing Revit workflow.

[Devin Johnston]

That's true, I just wish I knew what to tell them to avoid these problems.

[Smile of Fury]

Scott, thanks for the railing tip. That's 1000x better than what I've been doing. Can you tell me which link preset you've been using? I modified "Do Not Combine" so I don't bring in cameras, lights etc, but now I'm wondering if there's a better starting point. I guess it depends on what the end goal is?

[Scott Schroeder]

I tend to use combine by category since we don't do a lot of material in Revit by the time I get the 3d model. If you have materials already set, then I recommend combine by material as it keeps like objects together.

 

Using do not combine is not an option for us (and for anyone really) since we do larger projects and the end result is millions of individual objects that just absolutely slows Max down to almost an unworkable state.

[Smile of Fury]

Alright, thanks. I'm working on small residential projects...usually just one house at a time. I find the do not combine helps if I have to do different finishes in different rooms. If I combine by material or category then all my gyp-board walls are combined, even if some are to be white, some blue, etc. Now that I'm writing this, maybe combining them all and just assigning different material IDs is the way to go. Thanks for the advice.