Hi,

I ran into this weird bug where I end up with double, triple, or even quadruple nurbs patches after saving and reloading a file. The same happens when I join several objects.

The first time I thought I made a mistake by accidentally copying and pasting stuff, so I fixed it manually. But after saving and reloading the file, the exact same problem re-occured.

I tried using the Moi 3 beta, but that did not help either.

Does anyone know if this a known issue and how to solve it ?

I've put the file in Dropbox if anyone with more experience in Moi would like to check it: https://www.dropbox.com/s/asx0at7eqm0pvy9/starmania_work_v18.3dm

Thanks,

-Ronald

Hi Ronald, that is not a known issue, I will take a look at your model later today and see what I can find out.

- Michael

There are a lot of hidden objects.

Thanks guys.

As far as I can see the hidden objects are not a problem. When you hide everything and just leave the "cup" object visible, you can see there are several duplicated "patches". ( when you select and delete some you'll see there's another or sometimes more hidden under it )

I recreated most of the problematic areas, and it looks like the problem is fixed. I'm quite new to Moi and I suspected it to be more forgiving with booleans and trims. But maybe it was just sloppy modeling ;-)

I'm still curious how this can happen though.

Thanks again,

-Ronald

""""""""""""I'm still curious how this can happen though.""""""""""

Maybe describe your workflow on creating that object a bit. If you review your curves in the file, you have several duplicates and some just very slightly different.

If you are doing some particular selection methods, then you may be performing some operations with more objects than you think.......

Hi Ronald, I'm not able to reproduce the continual duplication problem over here...

Can you please post a more detailed set of steps on what you're doing?

Here's what I tried - I opened your file, then did a "Save As" to a file test2.3dm. Then I opened test2.3dm and did a "Save As" to test3.3dm, and so forth until I got to test7.3dm.

Then I examined test7.3dm and it seems to have the same structure as the original file, I could not detect any additional duplicates being created just from opening and saving like you were describing. I tested with v2 and with the current v3 beta as well.

One thing to note is that if you're using the "Import" command instead of "Open", then it is normal that you would get duplicates created, because that's basically what Import is for, it adds the content of the file you pick to the current model, retaining the existing stuff. That's different from "Open", which throws away any already existing stuff before bringing in the stuff from the file.

If that's not it and if you can reproduce the additional duplication without having used "Import", please let me know some more detailed steps so I can try to reproduce the problem over here and investigate it better.

Thanks,
- Michael

Thanks for checking the file Michael.

What happened was that I deleted the double patches, saved the file, but after reloading they re-appeared. As if they are created during the saving or loading of the file. I noticed a previous backup save is in worse shape then the one I sent you initially: https://www.dropbox.com/s/sliyjvr92a6mhs7/starmania_work_v17.3dm

I tried replicating what happened with file I've put in the link above just now, but I must have done something weird yesterday or it was the weather. Because when I now clean double patches they seem to re-appear no longer.

Maybe they got there because of a sloppy workflow? What I basically did was boolean the cup and star shape out of a big flattened sphere and extrude and fillet the resulting shapes. But maybe I should have used trims and projected network patches instead of booleans and a huge sphere. It creates better polygon exports as well I noticed.

Thanks again,

-Ronald

Hi Ronald,

> What happened was that I deleted the double patches, saved the file, but after reloading they
> re-appeared. As if they are created during the saving or loading of the file.

I seem to remember now that there was a bug in v2 where this could happen, it had to do with certain kinds of malformed trim boundaries that could make it difficult to traverse connected faces which happens during saving and loading.

But that's been fixed for a long time in v3 though. V3 makes extra sure that each face is only exported once even in those cases.


If you've been using v2 mainly, I'd recommend using v3 instead and see if the problem doesn't occur anymore, you can get the current v3 beta from here: http://moi3d.com/beta.htm

I tried again to delete the doubled patches in your previous file and then saved and reloaded and I couldn't get any doubling behavior to happen.


> But maybe I should have used trims and projected network patches instead of booleans and
> a huge sphere. It creates better polygon exports as well I noticed.

Booleans with a large sphere would usually be the preferred way, but you'd probably get better final meshing behavior if you rotated the sphere around so that the "pole" spot on the sphere was not right in the middle of the final area that will be kept. If you rotated it so the poles were on the side that would keep the "seam edge" of the sphere to be out of the final object structure and so you wouldn't get polygons connecting to a pole point in your final mesh in that case.

- Michael