What are the requirements for an object/scene to become XRef?


I just discovered XRef, it is just what I need. Was watching some YouTube tutorials, and the basic process is very straightforward. However, when I try to replicate the steps some times the “imported” XRef lands in my large scene as a number of non-connected parts.

The tractor model below made it whole. Others, not so well:


-Ramon F. Herrera
JFK Numbers


Where is the issue?

Are you using Xref Scene or Xref Object?


The problem occurs both with XRef Scene and XRef Object.

Will describe it in a little while. I need to prepare a good example.


JFK Numbers


See the mailbox that I have unsuccessfully attempted to import into my main scene:

For learning purposes I have attempted to import the model (both as XRef Object and XRef Scene) into the house to which I added a plane. See results:

As you can see, there is no “mailbox” object, there are 14 mailbox XRef parts, ordered alphabetically: pull handle, mail deposit door, frame for sticker, screws, etc. At the only time the 14 parts are selected is during the import. I try to relocate the parts on the lawn. If I miss a click it becomes very hard to select those 14 entities alone.

I am still not clear on the differences between “Import as Mesh”, “Import as Editable Poly”, “Body Objects”, etc. They seem to be related to my problem.

Thanks again, James,

JFK Numbers


I advice against using xref object unless you want headaches later - this is a half baked feature which has some major issues.

xref scene is much cleaner as it just references the other scene, however if you want to move the object you will need to link it to a dummy to move it. Xref works good for large scenes such as multiple buildings with details (which I assume you are testing for). If its for individual objects then I would just merge them into your scene.

From what I can see you are using scene explorer. try using the layer manager instead. However keep in mind this is only if you have placed this into a layer in the 3D file you are xrefing into your scene.

If your objects are coming in scattered instead of how you placed them originally then you have xform issues in the model and these will need to be reset in the original scene before bringing them into this scene. Generally this happens when objects have been scaled during the modelling process and the transforms have not been reset.

Import as mesh is an old default, can still be used in some cases for particular workflows. Import as Editable Poly is generally regarded as normal now. Some game engines will require you to output your objects as Mesh files (but rarely these days). I doubt this is related to your problem, generally the problem would be related to how the file was exported.


A handy feature is Grouping - if you wish to keep all the mesh’s separate (nuts, bolts, frame etc) but want to move all at once. Once you have a successful import, select your the parts of the Mailbox and in the top menu (File, Edit, Tools, Group…) select Group.

You can now select any of those items and move them entire group together as you would with any other piece of geometry.

edit: let me know if this helps, otherwise it would help if you show some more, and closer screenshots of each individual issue as its difficult to make out the exact problems you are having.


They are not scattered. Immediately after import they are in the precise space location respect to each other… without any “glue”, that is. They become scattered if I am not very careful, selecting them, and only them.

JFK Numbers


Use the grouping I mentioned above if you want to keep them ‘glued’ together.


Thanks for sharing your expertise, James.

Meanwhile, I have been experimenting. The workflow is this:

(1) Original model was done in SolidWorks. NURBS v. polys is an important issue for videos.
(2) Imported to 3ds Max, with several options (Mesh=ON/OFF, etc.)
(3) Once in 3ds Max, there are more alternatives: Open Recursively, etc.
(4) The issue of XRef Object vs. XRef Scene has been decided: Scene is more convenient.

I still have not reached a full understanding of all the variations, but have this to report:

  • Do NOT erase the “Helpers” before XRef import, they will serve as glue in the master scene.

  • The “Open Recursively” option is a factor as well.

JFK Numbers


What is the issue? What videos are you referring to?

Mesh on/off? Do you mean import as mesh?

You are referring to Groups?


Yes, the option is under the “Group” menu. I was trying to assign textures to parts of models imported from SolidWorks. Could not choose, for instance the door of the mailbox alone, it was part of a greater entity. A poster in the Autodesk forum suggested: “You have to Open Recursively”.

Now, I need to learn the implications recursive open and removing/keeping the helpers.

JFK Numbers


See image:


When importing SolidWorks models, import with “Mesh=OFF” is buggy.

See below:

JFK Numbers


You should not apply materials as a group, a group is just for keeping things together so you can move them easily or hide a bunch of objects quickly. Imagine it as a container filled with marbles, you can move your marbles together quickly. Opening the group allows you to move each marble within that container (even outside of the container) but when you close the group the container is now the size of where the furthest marble is located. If you want to apply materials open the Group first. Opening recursively is if you have groups within groups, this opens all the hierarchy together in one button.

Importing/Exporting between 3d softwares has its downfalls, they do not talk to each other so easily in some regards. You will need to experiment to get the exact settings to work for your particular workflow. Its often easier keeping thing in one 3d package, by implementing one new process to your pipeline you may find new problems with your import which you will need to troubleshoot. In my experience having no materials, a clean polygon mesh and export should give you almost no issues, its only when you are going from one render engine to another - all of which use different lights, materials, etc.


These ones, for instance:


They are in the humor department of my project. The human character is a well known professor, the bulldog is a poster (calls himself “Big Dog”) in the main forum about the topic. They are green with envy and scared shitless about my little project.

That video is postponed (it was becoming too expensive) but not abandoned. The mailbox processing taught me a lot about the NURBS vs. Polys issue. An important lesson was learned: For my upcoming video, serious, with the TSBD building of the highest rendering that I can afford, instead of relying on import from SolidWorks, the mailbox was redone from scratch in 3ds Max. It now has a perfect appearance and minimum poly count.

JFK Numbers


So you are using Polygon workflow in 3dsmax correct - not NURBS?


SolidWorks (the original, seen here):


Is based on NURBS or similar (parametric equations). When imported into MAX, the number of polys is absurdly high. In my first attempt I was thrilled: discovered that by removing all the screws from the original SolidWorks, I achieved a whooping 90% poly reduction count. However, that solution is not general. From now on, my SolidWorks models:


Are being remodeled in 3ds Max, from scratch. The rendering, in our trusted friend V-ray.

JFK Numbers


Better to convert your object to mesh before importing it into 3dsmax, this way you can control the subdivision count easier.


There is also an amazing plugin by Exoside called Quad Remesher. Its a good plugin which can adjust anything out of your control which you wish to adjust within 3dsmax after the fact.

Heres a quick test I did recently using that plugin.


I agree, but still better (twice as expensive, though): Redo everything in 3ds Max. Found a really great guy, a Freelancer who lives in Cairo.

Right now he is working in a object never modeled before. See below:

JFK Numbers


Well that depends on your final output. If you plan on finishing the project within 3dsmax then yes its smarter to begin and finish in 3dsmax if you can.

If you plan on taking this into the Unreal Engine later you better start doing that now because you will encounter even more issues later down the track if you dont.

edit: However that doesnt mean what you have already done in NURBS cannot be easily adjusted to Polygon mesh with optimal amount of subdivisions, as long as you understand how.