FBX or DWG export for max import?

[Brian Cassil]

Anyway, I will be happy when I am able to update my Max model with the Revit model in under 30 minutes. I would consider this to be effecient.

 

I think we are working toward's the exact same goal, except I would go so far as to say that getting updated models that I can work with into max under an hour would be acceptable. 30 minutes would be really nice but may be asking too much at this point.

 

With the DWG work flow, I am trying to map layers out of Revit that correspond with the materials of the building...

 

Another thing to look into, nPower has some special tools for importing Revit models into Max. You might be able to develop something off of that...

 

Again, the bottom line for me is about developing a workflow, not just importing models. Otherwise I might as well be pissing into the wind.

 

Have you had any success with creating a layer map that corresponds to revit materials for the DWG workflow? I have had a lengthy sit down with our revit expert and he is not aware of a method for doing this.

 

Also, has anyone been able to deal with the parenting problem that the dwg work-flow creates? I have tried several times to get the dwg cleanup script to work but it just doesn't appear to do anything at all, at least not in Max 2009. Also, exploding all the blocks in ACAD doesn't work because the resulting import to max ends up as a wireframe only, no surfaces.

 

Other challenges are how to deal with the materials. In the dwg work-flow if materials could be mapped to layers that would be great but we can't see a way of doing that. In the FBX work flow I get multiple copies of materials assigned where only one should be.

 

Lastly, we have had issues trying to only export the shell of a building with all the high detailed guts (toilet fixtures, interior stairs and railings, etc.) stripped out, without removing the necessary things like curtain walls etc. I think this is something that the revit guys need to work out but it's an issue for us right now.

[Brian Cassil]

Oh yes, and I'm going to be looking into the revit2max plugin offered by nPower.

[CRD]

We have had some success with cleaning up the dwg export in acad before going into Max. The key for us is to use the filter command to explode only blocks, not everything. Run a filtered explode several times followed by a good purge, then I like to import into Max by layer name and we end up with just the number of objects as there are layers.

 

The downside is we are finding that exploding some blocks messes with the geometry. Occasionally we'll find geometry missing from the buiding because of the explode process. I'm not enough of a cad/revit guru to know why some blocks can be exploded safetly and some cannot, but the process trims the model down considerably, so we take the risk and double check afterwards.

 

I know ADESK keeps pushing the material transfer perk of FBX, but most models I get are terrible material-wise anyway.

 

Colin

[kbotnen]

Seems there are no solution to the Block style issue yet? Anyone know a way to get to select all those object in a max scene? For the sake of just delete them. If everything is converted to mesh or poly those blocks could just be deleted, right?

 

-K-

[Crazy Homeless Guy]

I would highly recommend isolating each material type, dropping any instancing, and attaching the objects by material.

 

The model I am working on right now had 79,000 individual object, and several were instanced. This model took about 15 minutes to open. If you know Max, you should know that it hates lots of objects. It does not mind lots of poly's, but it hates lots of objects. I attached these object to each other by material. I didn't do all the objects, but I did do most of them.

 

I now have about 1,000 object. The file now opens in less than 1 minute, and I can move around almost as if there were no geometry in the scene.

 

This should also cancel out the block objects.

[Shaun Hamm]

I would highly recommend isolating each material type, dropping any instancing, and attaching the objects by material.

 

 

Hey Travis,

 

How are you doing this part in max? A bit more explanation of the steps to do this would be much appreciated.

 

I'm guessing any attempt at maintaining a dwg file link is gone with this method.

 

Thanks,

 

-Shaun

[kbotnen]

I started to clean my dwgs manually.

 

- I import one layer at a time.

- I choose a object, check its material, pick it in the mateditor, select objects by material.

- Convert to poly, choose one of the object, attach the others. Convert back to edit mesh. Poly is faster in attaching, but mesh takes less space when saving.

- If I stumble upon a block element I choose select similar from the quad menu and hit delete.

 

It works nice, but it should be scripted in some way. Any one up for something like that?

 

-K-

[Winniman]

I started to clean my dwgs manually.

 

- I import one layer at a time.

- I choose a object, check its material, pick it in the mateditor, select objects by material.

- Convert to poly, choose one of the object, attach the others. Convert back to edit mesh. Poly is faster in attaching, but mesh takes less space when saving.

- If I stumble upon a block element I choose select similar from the quad menu and hit delete.

 

It works nice, but it should be scripted in some way. Any one up for something like that?

 

-K-

 

Thanks for the interesting idea, I will keep in mind.

However, if I do this method, can the linked DWG file still be reloading?

Revit model became so heavy after import into Max, especially if the model has a lot of Glass Curtain Wall. I am still trying to reduce the file size.

[Crazy Homeless Guy]

I am still trying to reduce the file size.

 

It is not the file size that matters. It is the number of objects. Not even the number of polygons in the models matter that much. Just the number of objects.

Edited October 2, 2008 by Crazy Homeless Guy

[kbotnen]

It is not the file size that matters. It is the number of objects. Not even the number of polygons in the revit models. Just the number of objects.

 

For many the filesize do matter. It also affect loading times. But convert everything you can to editable mesh will help out. Also reducing the object count will reduce filesize. Attaching objects together will help on all these issues. But we need a scripter to help on that one

 

However, if I do this method, can the linked DWG file still be reloading?

 

I suppose NO. I work on finished geometry, so I havent checked out, in fact in the latest iteration I have imported instead of linking the file, so there is no communication back to Revit.

[Crazy Homeless Guy]

Hey Travis,

 

How are you doing this part in max?

 

Yes, this part in max.

 

 

A bit more explanation of the steps to do this would be much appreciated.

 

The model I am working on now was exported from Max using FBX.

 

After opening the model, I deleted all lighting and cameraas. I don't want those from Revit. I then ran the script mentioned earlier that hides the triangulation.

 

The next script I used was written by Olaf Finkbeine. This script creates a layer for every material. This step is probably not necessary, but it make the file a little easier to work with. I like layers.

 

I then manually turned on the layers, one at a time, and attached the objects on each layer. Because the layers were divided by material, and I only attached objects on that layer, there were no problems with materials switching on me. More or less, this made one object for each layer.

 

After you attach the objects of every material so they are represented as one object on the screen, your file will open a lot faster. In my case it was about 30 times faster, and that is not a joke. It has the same nunber of polygons, just fewer objects to load, and fewer instances to create. Both of those take a lot of time for Max to calculate.

 

Let me know if that doesn't make sense, I probably missed a few details.

 

I'm guessing any attempt at maintaining a dwg file link is gone with this method.

 

Yes, FileLink no longer works with this method. Maybe in the future it will. AutoDesk has implied that they are developing a FBX Link, but they also said FBX would answer a lot of headaches, instead it has frustrated people. AutoDesk marketing information implied to firm directors, and IT leaders that the link between Revit and Max is essentially seemless. Anyone who has tried this with a project that has 'size' to it knows better. In my opinion that was really a statement that should not have been made, it is a statement that has made my job more difficult. I hope AutoDesk is aware that the number of objects in the FBX file is a huge problem.

 

I still haven't given up on DWG, but right now I am thinking that the only way to manage these Revit files is to attach everything in Max so there are fewer objects. This can be done with either a FBX or DWG, but it makes the link an invalid soution, and creates extra steps in the workflow.

 

As you probably have experienced with FormZ to Max, the linked DWG's come in as one obect per layer, and everything on that layer is attached. If I can figure out how to do that while exporting a DWG out of an AutoDesk product, then an active DWG FileLink would be a valid solution.

 

Until then I am going to use a bastardized version of DWG FileLink that was suggested by AutoDesk itself, in one of its white papers. If you need a link to that white paper, let me know, and I will dig it up tomorrow.

Edited October 2, 2008 by Crazy Homeless Guy

[Crazy Homeless Guy]

It works nice, but it should be scripted in some way. Any one up for something like that?

 

I have been thinking the same thing.

Edited October 2, 2008 by Crazy Homeless Guy

[Crazy Homeless Guy]

For many the filesize do matter. It also affect loading times. But convert everything you can to editable mesh will help out. Also reducing the object count will reduce filesize. Attaching objects together will help on all these issues. But we need a scripter to help on that one

 

Hard drives and RAM are fairly afordable right now. At least last I have checked.

 

I stand by my statement that file size is a lot less of a factor on loading than the following, some of which are partially designed to reduce file size..

 

- number of objects

- number of instances

- how many splines are rendable

 

These are dynamic elements that Max has to compute everytime a file is opened. Often the time for this computatin is lot greater than the time it takes to load a file from the network into the memory of your computer. The downside is that you give up some of the flexibility of your model, but the upside is that the performance of your model is a lot more effecient.

 

I was not aware that Editable Poly's were faster on the attach, and that Edeitable Mesh's required less disk space. That is a good tip. I was not converting them to editable poly's, just leaing the as Editable Mesh's. On several of my attachments I was crashing the file. I was monitoring the task manager while using editable mesh's. Several times my paging file reached 11.5 gigs. If it went beyond, I crashed everytime.

Edited October 2, 2008 by Crazy Homeless Guy

[kbotnen]

As you attach object, filesize goes down. And if you convert stuff to editable mesh, filesize goes down. Good listing you had,

 

I also want to point out autosave. What does a autosave every 5th minute do to your computer when the file is 200mb? Does it save faster when the size is just 20mb? Less object, smaller filesize and decreased autobackup intervalls can do the trick for some of us on some of the really huge scenes.

 

You could ofcourse power your pc with the latest stuff every second month, but we all know that this is not the way to go.

 

My point is that we dont waste resources just for the sake of it. If we can go with a smaller/more efficient file we do it

 

required less disk space. That is a good tip. I was not converting them to editable poly's, just leaing the as Editable Mesh's. On several of my attachments I was crashing the file. I was monitoring the task manager while using editable mesh's. Several times my paging file reached 11.5 gigs. If it went beyond, I crashed everytime.

 

Had same problem. Attach spinning on forever. Convert all objects to poly beforehand makes it much faster. The editpoly has far more options so more stuff have to be saved with the object to represent its current state, thats why convert back to editmesh after attach. Also you could now delete all the block parent stuff since the object has been converted and attached

 

The next script I used was written by Olaf Finkbeine. This script creates a layer for every material. This step is probably not necessary, but it make the file a little easier to work with. I like layers.

 

This would be very handy? You could now just attach every layers object and you are done? 6723 mullion frames with same material, on same layer, attach? This is what I am asking for here?

 

-K-

[Winniman]

After opening the model, I deleted all lighting and cameraas. I don't want those from Revit. I then ran the script mentioned earlier that hides the triangulation.

I guess the script only works on FBX rather than DWG. Is FBX's file size smaller than DWG? and BTW, what script you are using in here?

 

The next script I used was written by Olaf Finkbeine. This script creates a layer for every material. This step is probably not necessary, but it make the file a little easier to work with. I like layers.

I like work with layers too. But again, what script you are using in here and where can I find it?

 

I only attached objects on that layer

Can you please share how do you attach objects in Max? Sorry for too many questions. I am new in both Revit and Max.

[alias_marks]

Here's my workflow I've found to work better than the fbx or file link or whatever. You don't get the material translation like fbx boasts, but like others have said, we usually don't get 'materialed' revit models to work with anyway.

 

-Export dwg from Revit

-Import dwg by color into Max (still get thousands of objects right?)

-export another dwg from within max, unchecking convert instances to blocks

-delete everything in the max scene

-re-import that new dwg file by color and you get about a 10 object max file to work with, that is usually pretty well organized by material.

 

Viola! let me know if this helps. Haven't heard of anyone else doing this...

 

I find this works with dwg files up to 100 mb in size.

[Crazy Homeless Guy]

Here's my workflow I've found to work better than the fbx or file link or whatever. You don't get the material translation like fbx boasts, but like others have said, we usually don't get 'materialed' revit models to work with anyway.

 

-Export dwg from Revit

-Import dwg by color into Max (still get thousands of objects right?)

-export another dwg from within max, unchecking convert instances to blocks

-delete everything in the max scene

-re-import that new dwg file by color and you get about a 10 object max file to work with, that is usually pretty well organized by material.

 

Viola! let me know if this helps. Haven't heard of anyone else doing this...

 

I find this works with dwg files up to 100 mb in size.

 

I read something like this on the Chaos forum, but I thought the guy ran into a problem with DWG export limiting the number of ply's an object can have. Not sure on that, but I think this is what they said.

[kbotnen]

-Export dwg from Revit

-Import dwg by color into Max (still get thousands of objects right?)

-export another dwg from within max, unchecking convert instances to blocks

-delete everything in the max scene

-re-import that new dwg file by color and you get about a 10 object max file to work with, that is usually pretty well organized by material.

 

Sadly this didnt work. Exporting another dwg from within max made max stop responding. killed the process after 20 minutes. The DWG is about 30mb.

 

-K-

[Jane Namenye]

This might be a slight tangent to this thread but I believe that the crowd that is viewing this might also be able to give me information or colloborate on a possible solution, so: here we go:

I work in 3ds max. I am looking at possible solutions to solve double work and here is what I am running into: I will do about 8 renderings of a new building being renovated including an exterior with a few additional renderings of specialized signage. Then when those are approved by an outside design group, it then gets handed to an office in another city to create all needed design development and construction documents, signage elevations and so on, thereby remaking a lot of models I have already created but of course they need them in CAD or Revit.

Additionally an outside mill then takes our renderings and creates shop drawings from those renderings to produce any needed signage (which for these offices is somewhat substantial).

There's seems to be a better way. So I checked out Revit. Rather simple inerface and seemingly quite well made.

But would it be possible or a good idea for my rendering unit for instance to "model" their signage in CAD or Revit and then render in MAX so when the mill has to produce them we can just hand over CAD models? Similarly for our exteriors and such, if we built in revit - at least a basic structure and then exported to 3D - we could then hand over the "as-built" model to the unit doing the construction documents in Revit. Seemingly saving much, much time. Before I propose such or even chase such options I wanted to see what pros and cons anyone else has run into - particularly since this is backwards to what most people do (Revit - Cad - approval - then 3D and final approval). Thank you for your time.

[kris McIsaac]

I think that sounds like an idea. If someone starts a model and it continues through the whole job their should be a lot less re-work and hopefully less stuff up's. The only problem will be creating a set of standards for everyone to stick to.

[Dave Buchhofer]

Digging into this now, wouldn't mind more script ideas that people think would be helpful. Currently I'm looking based off of the FBX export, with the hope that thats the one that will actually see further development from adesk, whereas dwg seems to have been

 

So.. There's Create 1 Material per Layer --Olaf's script

 

one of the Explode Groups

 

Working up a quick attach by material (Quick seems like a figurative term when attaching!)

 

Mass AutoEdge / Weld / ResetXform / LowerCenterPivots?

 

I'm sure theres something that already has the conversion from pro-materials to something that doesn't suck?

 

Also would be nice if there was 'something' that could instance and keep UVW's across revit file updates would be nice, and seems feasable, if not exactly simple.

 

Also I'm looking into if there is a way to automate export multiple 3d views from revit, which would let you set up viewtemplates in the revit file (Ext Skin, Int Walls, Fixtures/Furn) and easily split FBX's up somewhat from the single massive mess

 

this sort of relys on decent family conventions that include some basic materialing, after doing it a few times, YMMV.

Edited March 16, 2009 by Dave Buchhofer
(Adding links to scripts)

[Dave Buchhofer]

Working up a quick attach by material (Quick seems like a figurative term when attaching!)

 

Got one working here, which collapses a 10000 object scene down to about ~500 (most of the leftovers didn't have materials applied in revit) in something like 5 minutes.

 

All well and good, as it gets you an initial file to start working with fairly quickly, but doesn't help much in the iterative workflow yet.

[Crazy Homeless Guy]

Got one working here, which collapses a 10000 object scene down to about ~500 (most of the leftovers didn't have materials applied in revit) in something like 5 minutes.

 

All well and good, as it gets you an initial file to start working with fairly quickly, but doesn't help much in the iterative workflow yet.

 

Willing to share?

 

...Quizzy has a script for attatch by material on his site. it works, but I run into RAM issues when using it. I have 8 gigs physical, and a paging file sent to 12 gigs, giving me 20 total. The process of attaching objects quickly easts this RAM up, and causes my Max to hang or crash. So while I canuse scripts to assist with the process of attaching, I still have to spend a lot of time working through the files by hand.

[Dave Buchhofer]

yea thats what I'm running into now, it looks like the ram issues can be gotten around by attaching in smaller batches at the expense of speed (Say, groups of 50 objects), and by clearing out the garbage collector occasionally as you go.. Its still pretty time consuming, and the time per iteration seems to be going up with the number of polys in the collapsed object..

 

theres probably a few tricks that can be done to help speed it up still though. doing a few timed experiments

 

sharing depends partially on how much of this i do at work vs home

[Dave Buchhofer]

Dave Stewart did some research on what the best batch sizes are for attaching via script if anyone cares to adapt it to their code: It sped my time up by a *LOT* will post the results once i re-stabilize.

 

Teaser: 2.6million faces in 2601 teapots -> 108seconds to collapse down.

Edited March 13, 2009 by Dave Buchhofer