Archinect
anchor

Using .obj files in Revit

Uhg!  


We've been given an .obj file (point cloud type file) for an existing building that was 'laser scanned' to create a 'super accurate' existing conditions model by a developer.  Unfortunately I can't seem to get REVIT or even AutoCAD to recognize it and import it.  

The research I've done is that I need to convert the .obj file (or a .xyz file) to a .rcp or .rcs file type using ReCap Pro.  

Anyone have experience doing this?  How was the conversion?  How useable was it in REVIT?  Any input on this process would be greatly appreciated.  

Thanks!

 
Mar 8, 23 5:35 pm
JonathanLivingston

Do you have access to navisworks? You can use this plugin to get from OBJ to DWG: https://apps.autodesk.com/NAVI... 

That being said I have only done this once. It lost all of the texture images and was a total point cloud mess that needed to be re-drafted / modeled from scratch. You can use it only as a reference but any usable data form is going to have to be created.  Don't let them sucker you into "we have an excellent as-built model for you to start from" It is very much the opposite. Never again.  

Mar 8, 23 5:53 pm  · 
 · 

Thanks for the info. We've got Navisworks. I think the developer thought they would get a 3d model that an architect could use the create conceptual designs from. What they received is just a 3d file with stitched together images like what relators use when selling a house. :(

Luckily we're writing a proposal for this work so I decided to do some research into what it would actually take get a workable model out of this.  A three story warehouse with odd shapes and elevations - it's going to take some time to model this.  

Mar 8, 23 6:10 pm  · 
 · 
JonathanLivingston

Yes, it will take time. You will not get a workable model from that. At least not one you can rely on. These models for real estate agents are photogrammetry with the geometry derived from the photos. It's the same process and a similar accuracy as google uses to make the buildings and trees 3d in google earth. If I was writing a proposal for this there would still need the same time to measure and draft the existing conditions as if you did not have such an asset. sorry to say.

Mar 8, 23 6:17 pm  · 
 · 
joseffischer

recap pro is really easy to use if you have the software, and basically autosaves in .rcp.  I'm definitely the odd man out, but I hate importing point clouds into revit.  Instead I keep the .rcp open on one screen in recap and pull my dimensions from it in multiple locations across the room and then decide what my critical points are going to be.  I've done a lot of as-built conditions of 1890-1930s heavy timber this way where many of the walls weren't exactly square but not enough to always bother modeling it slightly askew.  Depended on the situation.  As a I often was doing this work for other PMs I liked saving the recap model with all my dimensions, archiving the as-built model also showing dimensions, and then handing the product over to the design team.  That way later on I could prove I accurately modeled things given the pointcloud provided in case something was off or somebody moved an existing wall during design.

Mar 8, 23 10:48 pm  · 
2  · 
joseffischer

Scans were usually accurate by batches.  We have a company, repro dynamics, in Atlanta that scans buildings for us by floor, by stair core, and then exterior, all as separate models.  I don't bother loading them together and still do some of my own floor to floor and gross building measurements to check against the scans. 

When we got a "full building" scan as one file and/or when dealing with many 3rd party scanning companies, I would find that the floor to floors were off, or that the scans picking up the inside of the building didn't fit into the scan picking up the outside of the building.  Hard to describe without literally looking at it, but so easy when you saw it.  "our model is accurate to .00001" .... ok, here's some boarded up windows, the plywood is 3/4" thick, the points representing the outside face of plywood cross through and into the space representing the inside by 3ish inches... so clearly somethings off.  I could go on.

Mar 8, 23 10:54 pm  · 
1  · 

It's very odd.  I just got nice clean pdf floor plans for the project from the person doing the scanning - they're using MatterPort.  I don't understand this.

This is a small snapshot of what we originally received:  


Then late last night we were sent  this:


Mar 9, 23 10:12 am  · 
 · 
JonathanLivingston

This is where AI in architecture needs to focus.

Mar 9, 23 12:07 pm  · 
 · 
sameolddoctor

Chad, in the past I was researching this - there are a few companies (mostly in India, China etc) that will take the matterport scans and draft in CAD and provide PDFs 9which is what its seems you have been provided with). 

I think they mostly use brute force and draw it manually. It may work for concept level, but I have found the drawings created by those firms are usually not upto par for any detailed work...at that point you may have to do an old-school as built drawing.

Mar 9, 23 12:14 pm  · 
4  · 

That's what I was thinking sameold - this is only for conceptual work. Even then the company isn't able to provide AutoCAD files.  

Mar 9, 23 12:16 pm  · 
 · 
sameolddoctor

Hmm - if you want dwgs, they are firms that you can find online that will take the matterport scan and redraw it for you. But yeah may not be needed for concept level work

Mar 9, 23 12:49 pm  · 
1  · 
betonbrut

I believe Matterport has a Revit plugin that can take the point cloud and then convert it into some level of detail within Revit. I haven't used this, though we do use Matterport as a means of storing and sharing 3D pointcloud information.

Mar 9, 23 4:14 pm  · 
 · 

I've never seen a REVIT plugin for MatterPort. I've even contacted MatterPort about this and they have no idea what you're referring to.

At most you can use ReCap Pro to convert an .xyx or .obj file to a .rcp or .rcs file.  Even the you're just getting the point cloud and no identifying information.  Basically you get a constellation of points in 3D - pretty much worthless.   

Mar 10, 23 12:48 pm  · 
 · 
betonbrut

Admittedly, I don't do this work in the office, we have our BIM/VDC folks do it and this thread/question has me asking more questions! In my brief discussion this morning, we are using Navisworks to essentially merge a revit model with the point cloud. For you original question, the point cloud may not be as helpful as your client thinks/thought. We do not do much TI or renovation work that would require accurate as-builts. We were using a point cloud file on some high rise work to verify a variety of as-built conditions back to the model.

Mar 13, 23 2:14 pm  · 
 · 

That's been my understanding as well - the point cloud file created by this process isn't good to use for existing conditions.

Mar 13, 23 3:31 pm  · 
 · 
newguy

As a rule of thumb, I would never rely on any model given to us by a contractor or client.  They'll often try to give you a model in an effort to try and reduce the schedule and often what you get is complete unusable dogshit.  I'm currently on project that when I joined was a core/shell model by one architect, and then an interiors model done by another architect.  The result was a complete mess and I ended up spending a few weeks completely re-building the model from scratch to bring it up to our office standards so that I could control for origin points, wall types, door types, revit assets, etc.  Even things you wouldn't normally think about like linetypes, fonts, annotation settings, etc will balloon out of control if you use a model generated from outside your office.

Architects in general need to stop thinking they can circumvent the initial start-up time in creating a model because it almost always ends up costing more time further down stream, as that "inherited" model will without fail, end up infecting your workflow and quality control.

Mar 9, 23 7:55 pm  · 
3  · 

I agree. I do think it's clients, specifically developers that think using things like MatterPort will reduce initial startup time. I've had high resolution laser scans done on historic buildings by professional surveyors. Even with the models being highly accurate (within 1/16") there is still a lot of work that we as architects need to do in order to use them.

Mar 10, 23 12:47 pm  · 
2  · 
JDubya

Chad Miller - I'm interested in this as well as we're recently working with a consultant that is experimenting with Matterport to produce as-builts. I'm super new to Matterport (and kind of skeptical) but here are a few things I've discovered that may be helpful:

There is a Matterport plug-in for Revit '22 + '23. I have installed it on '22. Search your Autodesk account for available apps.

File size matters. We were provided a 19.6GB .E57 file of an existing home... Revit (or maybe our machines) can't handle it.

Matterport can produce a BIM (.rvt) file if you provide them with the point cloud data/scan. Cost is something like $700 and I really have no idea what the deliverable is/looks like.

I have been told Matterport support is farmed out overseas and leaves much to be desired.

The Revit-Matterport interface is clunky at best as accessing Matterport through the Revit plug-in only directs you to a Matterport website for access to files there. IOW: I don't think you can't simply access a file locally or from your server/cloud; rather you need to be the end user of the Matterport license and the Revit license. We're a small firm and probably won't purchase Matterport licenses or equipment, but we'd like to work with consultants that can create the data and hand it off to us. So far, I can't find an efficient way to access and utilize that data in Revit. Beginner's learning curve no doubt, but I was hoping it'd be a bit more intuitive.


Mar 13, 23 3:43 pm  · 
 · 

We're not going to pay for a REVIT model or use the MatterPort plug in. After speaking with various BIM experts the plug in doesn't produce a good model and it can really mess up your REVIT file.

Mar 13, 23 3:53 pm  · 
 · 

Block this user


Are you sure you want to block this user and hide all related comments throughout the site?

Archinect


This is your first comment on Archinect. Your comment will be visible once approved.

  • ×Search in: