Hey all,

I have been given a .stl and a .max file of the same model and want to be able to open it in MoI, is it possible to convert these files, if so how? Any help would be appreciated.

Thanks
Alexander

The only thing you can is import the structure not the surfaces!
And from OBJ format
Polygons are not nurbs!
Load the Obj23dmWireframe converter
http://moi3d.com/resources

Thanks Pilou,
I'll give it a try.

Alexander

If the stl's are small enough, you may be able to convert them to stp files with stl2step from solveering..

Hi Alexander - those are polygon file formats.

MoI works on a different kind of 3D data than that - MoI works with a kind of object called "NURBS surfaces", which are a kind of spline surface, it's kind of similar to Bezier curves if you are familiar with those in 2D illustration programs.

Polygon model data is a much different type of data than that - instead of being made up of splines, it's instead made up of a whole bunch of little planar facets.

MoI can generate polygon data by dicing up spline surfaces into polygon bits - that's why you can export to STL or OBJ format out of MoI. But it's not so easy to take already diced up little facets and try to reform smooth longer spline patches from them, so that's why you can't import polygon data into MoI.

See here for some additional description:
http://moi3d.com/forum/index.php?webtag=MOI&msg=3880.2

But basically the model that you're trying to import has a different kind of data in it than what MoI works with at modeling time.

- Michael

Hello,

I know Spaceclaim can import STL data and use that as a reference to create geometry.

Hi OSTexo - unfortunately importing STL geometry that works really differently from regular geometry tends to lead to a lot of additional confusion and questions, like "why can't I do booleans or fillets on this particular object" and stuff like that...

I may end up doing something along those lines in the future as well anyway though, but for the time being just focusing on working with one kind of object type during model time tends to keep things more simple.

- Michael

Hello,

The STL functionality for Spaceclaim imports that geometry as reference, you effectively have to rebuild from scratch using that data, it's really not brought in as something to modify/use directly.

http://www.youtube.com/user/SpaceClaimCorp#p/u/5/Z5RR24RcOdw

Personally I think there are many other useful things that could be included in MoI before getting to something like this.

Hi OSTexo,

> The STL functionality for Spaceclaim imports that geometry
> as reference, you effectively have to rebuild from scratch
> using that data, it's really not brought in as something to
> modify/use directly.

Right, so the tricky thing about something like that is it's pretty easy for that nuance that it's "for reference only" to be lost on people - if someone just sees STL as a supported file type, and then try to open it and get a 3D model displayed on the screen, a lot of people then assume that they have opened up geometry to work with just like one of their other files. Then when it doesn't behave like other things they have modeled it is confusing and they wonder if something is going wrong...

Maybe if it was on some completely different dialog than the regular Open or Import dialog that would help avoid that kind of confusion.

- Michael

I recently took a beating from a guy in another forum who was sure there was a bug in a program because his 3dm file was empty when opened in the other program!!! lol I tried to explain there were differences, but he didnt want to have any of it.... :o

Hi Burr, yeah unfortunately there has been something of a trend recently where some rendering programs say that they support 3DM files, but what they actually do is only read polygon mesh data from the file and don't attempt to process the actual NURBS/Solids model data itself...

MoI on the other hand only reads and writes the NURBS objects and doesn't try to do anything with polygon mesh data in 3DM at all.

It can cause some confusion having really different kinds of data like that potentially stored within the same file format.

It's kind of more common for file formats to only contain one kind of data in them, the person you were talking to was probably used to working with file types like that.

- Michael

Yeah, actually he was a CAD/CAM guy, who received a file from someone else, and couldnt grasp that an "OpenNURBS" file could contain anything that wouldnt be read into his NURBS based Cad/CAM program (3dm is 3dm, right!)....Convinced it was a bug and proclaimed the software programmers were stupid idiots! :o

Can you imagine?? "Michael doesnt know what he is doing because MoI wont open this 3dm file, that is HIS filetype!!"

Anyway, an example of the confusion you were pointing out..