Revit to Max Workflow

[tampac66]

Hello,

 

I am just now getting into 3ds max and Vray and so far my workflow has been to import my revit file to FBX and import into max. Then i run a autoedge script, and a layer by material script so that i can add materials easily.

 

So far i have run across a couple problems.

 

1. MULTIMATS!!... These things drive me crazy. The layer by material script works great, except i then have like 100 multimat material layers. If anyone can help me figure out how to deal with these besides going through them 1 by 1 that would be great.

 

2. Materials from Revit (mental ray) show up as completely black and do not render at all in vray, they just show up black.

 

3. Scale. I cant seem to go the scale correct when i import. It always is way to big or way too small and my camera zoom barely moves. In the FBX import box what should i do with units to get the proper scale?

 

 

 

So thats what i do. I would appreciate any help to the above questions. Or if anyone has a better, more simple work flow let me know.

 

 

Thanks in advance!

 

Cameron

[Crazy Homeless Guy]

2. Materials from Revit (mental ray) show up as completely black and do not render at all in vray, they just show up black.

 

ProMaterials are not supported by Vray.

[tampac66]

Yes, thats not such a big deal since i would be replacing almost every material anyway, but i hate that they just show up black... at least they could default to a generic gray material so that it would show up in a test render.

 

Do you know of any simple way to deal with tons of multimat materials from Revit?

[bharris]

It will be interesting to see what the 2011 FBX improvements will bring.

[Dave Buchhofer]

the collapse by family options looks pretty helpful... be nice to use actual file linking, instead of the ghetto scripted version i've got set up now!

[tampac66]

Collapse by family would be really nice.

 

 

The things that bugs me the most right now is multimat objects. Without them i could simplify my project to 10 -20 layers. But as it stands.. i have my main materials... and then multimat1-multimat1000000000

 

Slows things down a ton. I wish i could make it so that the part of the object that is ... say... wood, would go to the wood layer, and the part of that same object that is metal, would go to the metal layer. Then i could move much quicker.

 

 

Is there anyway of doing that? Perhaps with a script or something?

[andstef]

Hello,

 

I'm playing with FBX models from revit right now, and I must thank you for bringing up the Auto Edges script, it work formidably well, I didn't expect it to work on surfaces with double curvature, but to my surprise, it fixed those too . Just the other day I was trying some similar scripts from scriptspot.com but somehow this didn't caught my eye.

 

I can't advise you on your multimat problem, but regarding the scale, I think you should check the units, I have units set to centimeters in Revit and the units are also set to centimeters in max (both the system units, and the display units). When I read your post I double-checked, and the model was imported at the right scale, so you should check the system units in max (I suppose that it is very hard to confuse units in revit, so revit should be ok). When I export the fbx from revit i leave every thing at default, and in max i choose the revit preset.

 

good luck

[Shaun Hamm]

a collapse by family tool sounds great...where did they announce this feature??

[Dave Buchhofer]

saw it in a "feature sneak peek" video over at kens blog at autodesk.. just a milisecond of them pulling down a "Group by" option in the FBX file linking video.

 

will be nice to not entirely break the linkages, as i have scripts to do all that now, but it needs to be redone every time the model changes and takes ~45 minutes to process a large model (heh)

 

there is a DetachByID script, but it isn't terribly fast when dealing with revitish numbers of objects..

[RevitGary]

Sounds to me like your "layer by material script" might be causing the problem. I import with fbx all the time.

 

Import fbx into a blank scene use the revit import settings use autoedge save the file as "link.max". Close the link file open another max scene

and xref objects into the scene .. xref the "link.max"

 

in the new scene select by materials to change the material and as you are changing materials you can add them to new layers.

 

now you have a xref link between revit changes and your max model...with a couple quick steps

[burdurky]

When I import FBX from revit 2010 into Max 2011 design the polys are a MESS. When animating it is simply a waste of time. When I export from Revit in DWG solids the polys come into max clean. But then you have the problems with hidden links. I use a script I got of the net to clean up the DWGs hidden links and stuff in the DWG file so I can group. But no materials come thru.

 

Why does everyone think Fbx is so good? I admit I am not expert but if Autodesk could show me a clean FBX import I would be amazed. I have tracked down "experts" who all say FBX is awsome but when I ask them to press f3 and statistics (7) and look at the polys especially on cylinders they are at a loss to explain the huge poly count and the mess that is shown, useless.

 

If you had a building in revit and you had to animate a simple construction sequence in max 2011 how would you do it so you had the least amount of work? Why should I have to redo stuff that is already done in Revit? Am I missing something, i hope so!

 

Do I have to link the files?

[Crazy Homeless Guy]

In my humble opinion FBX FileLink is awesome for smaller projects. Larger projects is where it suffers and becomes difficult to use.

[Dave Buchhofer]

In my humble opinion FBX FileLink is awesome for smaller projects. Larger projects is where it suffers and becomes difficult to use.

 

Travis, do you have a suggestion of an alternative for larger projects?

 

Mostly right now i'm just saving out different worksets to different fbx's and linking the building in parts for larger jobs

[Crazy Homeless Guy]

Travis, do you have a suggestion of an alternative for larger projects?

 

Mostly right now i'm just saving out different worksets to different fbx's and linking the building in parts for larger jobs

 

None that I am willing to hang my hat on. On the last large project I set up custom DWG layer mapping for exporting from Revit. By doing that I was able to control what layers items were on. I then tried to use DWG FileLink to bring it into Max.

 

That worked, and produced a more efficient model than the FBX did, but I wound up having one major problem. The vertexes were not welded. So I wound up binding the FileLinking, and manually welding the vertices.

 

I was hoping I would be able to keep an active link to the Revit model using this method, but in the end I wound up binding and modifying because that seemed like it would be a more efficient method than trying to modify the Revit model itself. This was due to many materials and objects being named poorly in Revit, and do to the vertices not being welded.

 

I originally tried to import this model using FBX, but it was producing a lot more vertices using that method, which resulted in a slower model, and nearly impossible to rotate and navigate the model using my Quadro1800. I haven't tried the latest FBX plugin build for Max, so I don't know if it would be more efficient.

 

I also have not done any more research since I originally started researching vertex numbers using different import methods, but in the attachment you can start to see how the numbers vary dramatically. I also didn't inspect these models close enough to really figure out why the numbers were so different, but all of the numbers were generated by exporting the exact same information from Revit in different formats, and utilizing different methods to bring it into Max.

 

Also, ..these are not the numbers for my last large project that I wound up doing the DWG mapping on. That project was 6 to 7 times the size of the project that the one detailed int he attachment.

[WAcky]

Hi folks,

 

Now that its quiet at work I've started writing a paper for our intranet on my revit to max workflow. After trying so many different ways of getting data from revit to max I've found the best way for both performance and organization is the following (based on the job im currently working on)

 

In revit I export each category as its own .fbx file and I end up with 14 files ranging from 2.4mb to 50mb each for a total of 175mb of data.

 

I then in max use the fbx file link and use the combine by material preset with cameras and helper objects disabled. After linking each file, I bind them (this is an option you'll have to decide whether it's necessary for you) and end up with a layer for each category.

 

I then do a vray scene convert and up with a file containing over 2mil polys at only 30mb in filesize. Renders are nice and quick and if I resist showing maps in the viewport I achieve up to 150fps viewport speed on our standard Dell cad boxes.

 

this allows one team to do interior renders by file linking in their geometry while I can do exterior shots.

 

There's still a lot more R & D to be done with how I'll manage updated geometry while keeping the file organized etc but it's looking promising so far.

 

I think the biggest tip is to make sure you use the file linking dialogue and not the straight import option as you'll have far more flexibility with how your geometry is imported and it will come in with far fewer errors.

[Justin Hunt]

it all comes down to how FBX tesselates the model on export. It uses a similar (if not the same) process when tesselation occours for rendering. Which explains the high poly count and the rather messy triangulation.

 

It has been suggested to set up different worksets depending on what you are exporting, such as using dwg for long, curved objects like handrails and FBX for larger flat objects like slabs and walls. To me this would be fine fro msmaller models but a nightmare for larger ones.

 

As to units, Revit used inches as its sytem units. So regardless as to what your working units are its been recomended to set Max system units as inches too. this should solve some texture scale issues.

 

So far the quickes methode we have found to clean up a fbx model it to import it into max, export it out as OBJ and re-import the OBJ, sure you will loose the material assignments, but it does bring in similare objects as one, such as mullions and glass panels.

 

jhv

[WAcky]

I should also mention if you use the combine by material, it will name your objects based on the material they were assigned in revit which makes it a fairly easy task to apply materials. Object is named "concrete warm grey", apply my material named "concrete warm grey" and so on.

 

Good until you get onto the dreaded "generic" material...

[WAcky]

Another note: I get no triangulation with the file link method...

[Justin Hunt]

do you mean that you can see all the edges?

 

One thing to look out for if you have curved surfeces, is messed up triangulation. especially if you collaps the mesh to editable polly. First collaps to editable mesh, make all edges visible , then convert to editable polly.

 

jhv

[Dave Buchhofer]

I think the biggest tip is to make sure you use the file linking dialogue and not the straight import option as you'll have far more flexibility with how your geometry is imported and it will come in with far fewer errors.

 

I'm working in basically the same style, just using Work sets instead of category to break it up, and collapsing by material types usually on import. If i could just get the export from revit automated it wouldn't be so bad. whether it stays as a link or is bound depends on what type of project it is, for renderings/animations i tend to just leave it linked and update as the job progresses.

 

Here's a little maxscript snip that will link a directory of fbx files, edit the last line to point to the file locations.

 

--Mass File Link and Save.
--Preset.ByRevitFamilyType.
(
fn fileLinkEntireDir theDir wildStr =
(
	setWaitCursor()
	if theDir!=undefined then
	(
		local fname=theDir+"\\"+wildStr
		local fArr=getFiles fname
		print fArr
		if fArr.count!=0 then
		(
			for f in fArr do
			(
				try(
						FileLinkMgr.attachWithPreset f "Preset.FBX" showUI:false
				)catch( print "failure while importing the file: " + f)
			)
		)
	)
	setArrowCursor()
)

fileLinkEntireDir "//path/to/revit_files/" "*.fbx"
)

 

Travis, i'll take a look into the layer mappings, sounds like it could be a useful one to explore.

[WAcky]

Thank you! I have the advantage of having some Revit consultants at work but this is still new ground for them

 

Being able to auto export from revit would make a very streamlined process.

[troyh]

Hey everyone- I've been a member for a long time, but I don't think I've ever posted anything. I'm changing that today. I'm finding some of the same issues when trying to utilize Revit 2011 exports for use in Max Design 2011.

 

The best method I've found for a clean model is the DWG export as solids. The FBX is fantastic for smaller projects when polycounts don't matter, but unfortunately I'm dealing with a huge dataset. My Quadro FX 3800 won't push the model very efficiently at all. FBX is nice because it will allow for easy material grouping etc, but these large chunks of geometry are terrible on the system and are creating huge files and meshes.

 

The main problems I'm having with the DWG is first the blocks which just get in the way, and the geometry that doesn't convert well to solids like complicated curved sloping roof systems. Therefore you have to export certain elements like that as Polymesh which you might as well use FBX when you go to that type of export because the polycounts still go out the roof just as FBX does...

 

Here's the polycount difference in my current model from FBX versus DWG solid export. 48m in FBX reduced to 8m for the DWG. That’s a huge difference especially when you have a large dataset like this. The files size is directly related with the FBX coming in at 490mb for the full model and DWG around 72mb. Huge advantage in model efficiency, but large problem with converting model into materials easily while maintaining easy workflow for updates, which leads me to my main question.

 

Justin wrote:

 

So far the quickes methode we have found to clean up a fbx model it to import it into max, export it out as OBJ and re-import the OBJ, sure you will loose the material assignments, but it does bring in similare objects as one, such as mullions and glass panels.

 

 

Justin - Can you elaborate a little more on the export settings for the OBJ export above? I've tinkered a little with this and it's obvious why the polymesh isn't efficient because this brings the face triangulation into view when you re-import after exporting to OBJ. Using the autoedge script I can clean the geometry up, but the model really isn't any more efficient or clean. Can you confirm that your process will in-deed clean-up the geometry polycount issues and if so what is some of the correct settings to use for exporting and importing if so?

 

If this OBJ export/ import process doesn't work then I'm under the impression that FBX is only for smaller datasets as mentioned previously in this string by Travis. The DWG export creates a way more efficient model for large datasets to work with, although the down side is you can encounter missing or incorrect geometry in some of the more complicated datasets.

 

At this point, I'm maintaining a file link with my DWG exports with some of my roof system as polymesh export versus the solids and it's working very well with a smaller file size and polycount overall. At some point I will have to bind that link, but it’s nice for now while updates are still be done to the Revit model.

 

If Autodesk could just fix the FBX export to convert most geometry to solids versus mesh utilizing mesh only for certain geometry that requires it then I would be using FBX for all exports. What a pain!!!

Edited March 8, 2011 by troyh

[mzagorski]

I came across this thread while trying to make sense of trying to get 3ds Max Design 2011 to play with a model from Revit Architecture 2011. I've been thrown into the fire with the task of taking a 110mb Revit model of a high rise building into Max for rendering and make it all look pretty. Really interested in advise on what to do / what to avoid. Not sure what you guys would call a large dataset. 110mb? I exported to FBX but from what I've read it sounds like that is a view-specific deal. Can I export to FBX, take into Max, and do camera matching, or should I be looking more at exporting to .dwg first?

[Dave Buchhofer]

You can export to fbx from any 3d view, by view specific they mean that things hidden in the 3d view are not in the exported model, EX: most of the time i hide handrails by category since they're utter shite in revit unless someone that actually knows how to build familys set it up (Read: stupendously rare)

 

Also for large datasets i tend to export by worksets.. really it all depends on how the building was set up in revit. break it down into many separate exports if you're not going to be re-loading the model every week... if its a heavy in progress job, well, you're sort of limited in what you can do to make your own life easier

[Crazy Homeless Guy]

I came across this thread while trying to make sense of trying to get 3ds Max Design 2011 to play with a model from Revit Architecture 2011. I've been thrown into the fire with the task of taking a 110mb Revit model of a high rise building into Max for rendering and make it all look pretty. Really interested in advise on what to do / what to avoid. Not sure what you guys would call a large dataset. 110mb? I exported to FBX but from what I've read it sounds like that is a view-specific deal. Can I export to FBX, take into Max, and do camera matching, or should I be looking more at exporting to .dwg first?

 

I consider an FBX over 50mb to be large.

 

Make sure to strip the EXR file that Revit often tries to put into the FBX also. This will save you 20mb or so.