Problems with the positions of XREF objects

[dacosdesign]

Adding an object/assembly by XREF works fine initially. After closing the scene, updating the original model and re-opening the scene, the XREF object will have all new objects out of position. Any ideas...

[hagen.deloss]

Hello @dacosdesign

Thanks for posting your question to the forums! Hmmm, that sounds frustrating, I hope I can help you work through this issue.

What version of 3DS Max are you using?

When you say "out of position", what do you mean? do the xref objects snap back to world space zero?

I would suggest bringing in all your objects into a fresh scene and seeing if that helps. I just tested Xref in 2019.1 and couldn't reproduce. Here are the steps I took to try to emulate your environment.

• I loaded a blank scene 
• I went to file>reference>Xref Objects and brought in 2 models 
• I saved my scene
• I loaded up one of the externally referenced scenes and made some new objects, and then saved ( I made sure to note their coordinates)
•  I loaded up my scene with the Xref objects and noted the location of the new objects where the same.

If there is anything I left out on how to reproduce this issue, let me know! It may be the version of 3DS Max is different 😄 I can test on older versions just lemme know! Talk to you soon

Please select the Accept as Solution button if my post solves your issue or answers your question.

[dacosdesign]

Thank you for answering.

I am using 2018 servicepack 4. I added target lights and their position changes & so does the target. Not even close to the original. This happens with a number of scenes so starting again isn't an option. I have linked existing hydraulic cylinders to their pivot points this morning. After opening the scenes that this machine has been added as an XREF, the cylinders are metres out of place. Images attached.

[dacosdesign]

This is the same machine in a different scene. The cylinders are almost accurate but the top cover has moved completely out of place, two lights are off the page & the other lights aren't pointing in the same direction. Impossible for me to start again.

[hagen.deloss]

Hello @dacosdesign

I tried to reproduce lights/objects externally referencing in incorrect locations but wasn't able to reproduce it (yet). I did some digging around and it looks like you aren't alone! 

Lightcube seems to have encountered similar issues on this thread, and had to fall back on Max script for the answer, here is that thread.

I would like to try to reproduce this issue, is there any way I can get a copy of 2 scenes that are having this issue (one to Xref)? you can either post here on the forums in a zip folder, or send me a private message with a file sharing link. If not the work files you have, but a re-creation of the issue? 

In the meantime, I will search the internal database and ask a few colleagues if they have seen similar behavior. 

Talk to you soon!

[lightcube]

Presuming that you brought the assets in from the XRef Objects dialog, the problem may be that the tracks are being controlled in the original file (like transformations, etc). These settings can only be set when the XRef is first loaded, so it may be necessary to recreate the scene.

Look at these docs on the XRef Record List and take note of the different Presets. Different track merging presets will affect your XRefs differently.

For reference for anyone looking at a similar problem when loading XRefs via MAXScript, see XRef Object Problems. That page has a similar issue but is rooted in loading via MAXScript. You may be able to adapt the solution for your current scene after you've moved the objects to their correct positions.

An untested solution that does not include recreating scene would be to select the objects in your scene that are xref objects after you have them where you want and paste this into the MAXScript listener and hit ENTER:

for obj in selection do obj.transform.controller = prs()

[hagen.deloss]

Hello @dacosdesign

I wanted to let you know I received your files and  am setting aside some time to look through the issue today, I will get back to you as soon as I figure anything out! 

It sounds like you are encountering a few different things; the center pivot to certain objects resets itself when you xref it, and objects that you xref spawn far away from their origin in the externally referenced file.

You sent me 4 files with a large amount of objects, and from my understanding the Cylinder that is linked to your  jetting tool is the Xref that spawns away from its intended location? I will test it out and get back to you as soon as I can.

Talk to you soon!

[dacosdesign]

Thank you for your time & also to lightcube for the input. Yes, the pivot point does reset itself in the examples that I sent & unfortunately, yes the objects do spawn away in some of my models. Autodesk are so close to XREFs working how they describe on line. I really need the luxury of one XREFs but as you can imagine, if I add linked/look-at constraints to two doors on a four door car and then later would like the other two doors to link/look-at in a similar way in multiple scenes, I can't afford the time to change every scene. Max recognises changes but just doesn't seem to translate them properly. Soooo close...

[hagen.deloss]

@dacosdesign

The attached file is for testing purposes, this thread will be updated soon 😄

[dacosdesign]

Thank you, sorry I missed your call. I think we're an extra hour out. Wednesday is the only day I need to rush away. If you can please call again tomorrow or I can call you if necessary. Thank you for the file, I'lll give it a go tomorrow. It is now 17:51 here at the moment. Hopefully speak soon. Dave

[hagen.deloss · Accepted solution]

Hello @dacosdesign

After our call and chatting with @raiden_xavier, we outlined that there are two issues, both in relation to Xref feature.

• In regards to an Xref file: when an object has a "look at" constraint applied, and the object's pivot point is changed, its location will change drastically in the file it is Xref'd in.
• In regards to an Xref light: when a light with a "look at" constraint applied is moved, its location will change drastically in the file it is xref'e in.

Raiden has logged this issue in our system, and development is investigating it. We don't have access to their release schedule, but I will post back here when I'm informed of any progress. 

I would encourage you, for the time being, to see if you can merge your scene components together after applying all the constraints. I'm sorry, but we weren't able to come up with another decent workaround for this issue. If you do find one, please let me know though!