topic Re: convert multiple instances to object in Maya Forum

convert multiple instances to object

Anonymous — Mon, 02 Jul 2018 14:04:14 GMT

I have a scene composed of multiple instances that make up a complete object (say repeating sections of a train carriage or seats) after finishing the modelling I now have the complete object which I need without any instance on it.

if I select all the objects and do modify-> convert instance to object, various parts of this actually disappear,

if I duplicate them the same thing happen, same thing if I export to obj.

the only way is to export to fbx but that destroys the materials.

is there an actual way to retain and convert all instances of a geometry as a separate object without tedious manual processing? maybe some script?

thanks in advance for any pointers.

Re: convert multiple instances to object

sean.heasley — Mon, 02 Jul 2018 14:45:37 GMT

Hi @Anonymous

Have you tried going to Mesh->Combine?

This will combine everything into one object and whenever you need to separate them again you can do Mesh->Seperate.

Please let me know if this helps or if you need any more assistance!

Re: convert multiple instances to object

Anonymous — Mon, 02 Jul 2018 14:47:32 GMT

thanks Sean,

combine has the same effect as the others unfortuantely, one or more of the copies disappears

Re: convert multiple instances to object

sean.heasley — Mon, 02 Jul 2018 14:49:45 GMT

Hi @Anonymous

Hmm ok.

When you get a chance, can you please zip and attach the scene file here or via dropbox/google drive or another file sharing program so I can take a look at it?

Re: convert multiple instances to object

Anonymous — Mon, 02 Jul 2018 15:07:10 GMT

@sean.heasley that's a bit tricky but here's some quick steps to reproduce: it seems to happen with instanced groups

create a cube and group it,

duplicate special (instance) the group a couple of times,

select all and try combine or any other method.

on my end they just vanish except one

Re: convert multiple instances to object

darioOrtisi — Mon, 02 Jul 2018 15:03:50 GMT

Have you deleted all Histroy and/or deletd all constraint after deleted histroy?. This happened to me.

Re: convert multiple instances to object

Anonymous — Mon, 02 Jul 2018 15:06:41 GMT

@darioOrtisi seems to happen both with or without history

Re: convert multiple instances to object

mspeer — Mon, 02 Jul 2018 19:21:50 GMT

Hi!

If you group the objects and instance the whole group not only the mesh/shape will be instanced, but the direct transform node too (with the identical UUID) making it impossible to distinguish between those objects.

There is currently no workaround or solution i can offer.

Please report this problem (bug?) to Autodesk.
Help -> Speak Back -> Report a Problem

Re: convert multiple instances to object

sean.heasley — Mon, 02 Jul 2018 19:33:06 GMT

Hi @Anonymous

Thanks for the repro steps!

Like @mspeer said, this looks like an issue with Maya and I've logged it with our dev team so they can work on a fix for a the future.

Re: convert multiple instances to object

Anonymous — Mon, 02 Jul 2018 19:41:23 GMT

thanks a lot @mspeer and @sean.heasley for logging in the issue, fingers crossed it'll get sorted soon enough.

in the mean time I happened on a workaround with this code, credit goes to lesterbanks

its fairly slow on large scenes and I'm losing shaders on some pieces so would be nice to have an actual solution implemented by autodesk.

# Python code
import maya.cmds as mc
import maya.OpenMaya as om

def getInstances():
    instances = []
    iterDag = om.MItDag(om.MItDag.kBreadthFirst)
    while not iterDag.isDone():
        instanced = om.MItDag.isInstanced(iterDag)
        if instanced:
            instances.append(iterDag.fullPathName())
        iterDag.next()
    return instances

def uninstance():
    instances = getInstances()
    while len(instances):
        parent = mc.listRelatives(instances[0], parent=True)[0]
        mc.duplicate(parent, renameChildren=True)
        mc.delete(parent)
        instances = getInstances()

uninstance()

Re: convert multiple instances to object

camrynCG68D — Tue, 16 Feb 2021 13:50:18 GMT

The way I've gotten around this is by exporting as an FBX and reimporting into the scene. This works with Maya LT as well as regular Maya -- in the full version there should be an option in the export settings under Geometry to Preserve Instances.
I need them as OBJs to import into another software that doesn't accept FBX, and so this work around helped me.

Re: convert multiple instances to object

sdouvilleAATP5 — Fri, 22 Jul 2022 13:05:41 GMT

That code is gold. Thank you

Re: convert multiple instances to object

Gillaria — Sat, 01 Apr 2023 17:56:18 GMT

I just want to say that the problem has not yet been solved, despite the fact that 5 years have passed.
Yeah, Autodesk is famous for solving problems in its products.

Many thanks to @Anonymous, the script works well.

Re: convert multiple instances to object

sktvete — Mon, 25 Nov 2024 11:19:51 GMT

Almost 6 now, @Sean Heasley

Re: convert multiple instances to object

jonathan.beviere — Mon, 17 Mar 2025 16:14:51 GMT

Select all the instances

In Modeling Menu Bar :

Modify > Convert > Instance to Object