My workflow is to leave Maya as quickly as possible. That means opening the dataset in Maya, maybe flipping some objects that have wrong normals and that’s it. Write to fbx and import that in Max.
Welding works just fine using the ProOptimizer. Smoothing is never ever to be touched with CAD data. No need for that, as the data you import has to look good in the first place. If it doesn’t, something went wrong during export/import. Smoothing on CAD can not work by design, and I am afraid would be the same in Maya.
Artifacts often appear when you do certain operations on the wrong type of object. Unwrap UWV on edit mesh always breaks normals. You have to convert to editable poly first (select objects to convert, then right click, convert to edit poly). Operations like unwrap and reset xform should work just fine now. Not sure about shell, that thing has its own problems. Most of the problems with artifacts arise because there are these two different types of meshes. You have to know when to use one or the other. Same for flipping faces, both types have a function for that, but they do different things. One flips face normals, the other vertex normals.
Interesting. It’s not something I’ve ever used, so I’ll have a look. Welding inside an editable mesh/poly or using the vertex weld modifier has always caused me problems.
Just to clarify, I don’t mean subdividing. I mean using the smooth modifier in Max to get rid of faceting and/or jagged reflections on insufficiently tessellated data. But it rarely works, without causing more problems than it solves.
Again, I find that simply converting anything to edit poly messes up the normals immediately. Strange that we have such differing results. Perhaps something to do with our fbx export/import settings?
It works. In the merge section, tick merge vertices and set threshold to 0.0. Also, keep normals and protect normals should be checked. Leave everything else at default, press calculate. The amount of vertices should be reduced significantly while everything else should look exactly as before. No artifacts or anything.
Yes, we are talking about the same thing. This never works on CAD data. If there is faceting on your objects where it should not be, either something went wrong on import or the tesselation just is too low. Nothing you can do about that in Max I’m afraid.
Please make sure to right click->convert. It really makes a difference. Slapping and edit poly modifier on top of edit mesh instantly breaks normals. If you want, you can send me a single part you are having troubles with, so I could check what’s wrong. Very rarely had a part that was unfixable in Max. It can do a lot more out of the box than people think.
I always use the presets in the dialogues of both programs. I think Autodesk Media and Entertainment. Hardly ever fails, if it does, try alembic. Also works very well.
John and Oliver, some interesting points you bring up there. I have a question for you both.
What if, I get the RAW CAD data, not Maya files, and not exported from Maya to fbx, but the RAW Catia 5 data (or in some cases the STEP files)
How do I get that into a usable form into Max, considering I don’t have Maya?
Most of the Maya files I have used geo wise come in just fine, ‘fbx - media/enetertainment preset’ in and out nothing else needed regards to smoothing etc,
If you was delivered a raw Catia file, I would imagine you would need a new pair of pants and a lot of time, not typically done from my experience,
I think in general the car company’s have their data prepped by certain company’s ‘rtt’ to be then delivered to cgi guys, prepping catia or alias files for poly rendering is an ugly and time consuming process, if working from an engineering file, so hope it comes as prepped poly’s, but even then the prepped files can be quite complex.
How much can I expect to pay for a typical exterior car model, if I have to get somebody like RTT to prep the RAW catia for me and deliver a MAYA or FBX file so I can take it from there?
It depends what software you’ve got.
Personally when I get Catia data, I take it into Alias Surface or Rhino first, because generally you need to strip all the B surfaces to make it in the least bit usable.
Then I’ll either tessellate it in Showcase or take the nurbs into max with PowerTranslators.
You’d be surprised. I’ve had quite a few jobs come in as full, unsorted Catia data. And to be honest, when I know the client well enough, I often request it, rather than having to put up with what RTT have done.
With RTT? An absolute fortune, I’d assume!
But if you’re serious about it, drop me a PM, and I’ll give you a quote on it.
How long would it take you too sort a Catia model generally John?
I can see the benefits of sorting the data yourself, and I would personally prefer it, that way you know exactly what your getting, I just can’t imagine I would ever be given the time on a real job,
Best thing that can happen to me is getting Catia files straight from the client. No RTT to interfere, no Maya. Max 2016 introduced a superb new import algorithm that handles .step, .iges and even .catpart very very well. There basically is a slider for the tesselation quality and that is it. Recently completed a job with some rifle scopes delivered as catpart, worked like a dream. Also got some head and rear lights the other day as iges, worked there, too. The data might be complex, but everything is there, no missing B-sides or stuff like that.
Really, you don’t want that. It will cost a fortune, and you get messed up data afterwards. Fixing their stuff is a nightmare. I’d rather get the raw CAD data then anything from RTT. And that is why I demand headlights and stuff to be delivered as CAD files.
There’s a flipside to that though. That’s all fine if you’ve got a bit of Catia data in amongst the prepped stuff, but try the whole car with all it’s B-surfaces and mountains of unnecessary crap, and you’re not going to have much fun dealing with it in the viewport. Or waiting half an hour for the file to save.
I’ve got some Catia data here for a car which is bordering on 60 GB. You can’t just take that into Max without some serious work beforehand.
The ideal situation for me is a mixture. Sorted data from RTT, Burrows, or similar, and the nurbs surfaces on hand for any areas you need them.
Oli and John, it would be great to get some knowledge on parts of the car that are best to get the catia data for,
Lets say headlights for example, with some data I have from rtt, the headlights look cool on first inspection, then I dig deeper and the bulbs are replaced with blanker geo, some parts seem to have been skipped etc,
Is this the same problem you guys are having? For example to do a headlight on shot, there dosen’t seem to be any detail, seeing light through glass etc,
Good to know the problems you guys come across when your not doing the prep yourselves.
Also would the Catia data have materials assigned? With naming conventions? So you can convert them all when you get them into cgi, obviously not the shader properties just the right placeholder mats on the right parts,
Is there anywhere were I could get hold of a file to practice with? and learn the prep side of things, I know you guys arn’t aloud to share this stuff for obvious reasons, but anyone know of anything good thats publicly available?
RTT randomly deletes the backside of some glass parts or splits them up into several different pieces. But Vray (or any other renderer) would need them in order to calculate correct refraction together with a fog color (for coloured glass like rear lights). Sometimes entire glass parts are missing.
Sometimes you do get material assignments, mostly you don’t. Usually is not a big deal, because from experience you can already tell what material might go where. Often you get reference photos, too.
A site like Grabcad is a good source to get free catia data. Mostly simple objects, but as a start that should be enough.
