topic Re: 3ds max fbx file link: how to preserve instances? in 3ds Max Forum

3ds max fbx file link: how to preserve instances?

zvsmail — Fri, 19 May 2023 20:29:25 GMT

Here's an issue.

I have plenty of absolutely identical houses (over 1000 units) scattered over terrain in Revit. FBX source file is about 12 Mb as it understands instanced geometry. Each house is instanced inside FBX. That's clever.

However, when I link this file to 3Ds Max and save it - 1.3Gb(!). Holy, no instances seem to be supported by Max - everything was collapsed into individual geometry. Whatever I do: by Material, by Generic FBX, Do not combine - no luck. No instanced geometry in MAX.

So my question is: any way to fetch instanced geometry from FBX to 3D Stdio Max instanced geometry respectively?

Re: 3ds max fbx file link: how to preserve instances?

darawork — Fri, 19 May 2023 23:34:17 GMT

Hi, as far as I know, no.
Fbx file format contains some handy information, like UVs, Materials, maybe more... but Instance information, I don't think so.

What I'd do in that particular situation is to not fill up the Max Scene file with 1000 similar items, that max thinks are different.... but maybe just bind the Revit File or FBX if it's live linked and not going to change in the future. Then delete 999 houses and make instances of the houses yourself.

If you seperate the houses from the site in Revit, and solely have one Site Worksheet and one Houses Worksheet, then export both as seperate FBXs, and live link the Site... but import the Houses as a seperate process then you can use a script like this "Make Instances": https://www.scriptspot.com/3ds-max/scripts/3ds-max-convert-unique-objects-to-instances-plugin

There are a lot of ways to instance Houses after import, or binding. Or if they are going to change, in the future, xref them in. I don't like xrefs though, or proxies, or file objects... when used when dealing with loads of houses. Max takes ages resolving them at render time, pharsing Geometry, or resolving Proxies, and their uvs and materials. If your computer can handle it, just try to keep everything in the same file. I work with housing scenes of over 40m polys regularly, and Max copes with them really well. Render times are 30mins to 5% noise in Corona. Rendering starts up in about 30secs, no waiting around.

When you have your scene as you want it to render, I highly suggest collapsing everything to 'Modifier Stack Result' in the Collapse Utility Tab. And also if you are sure nothing is going to change; Attach all similar Materials and Material IDs by Geometry. So you have all your 'Glass' in one complete object, Or 'Window Frames', or Floor Slabs... etc. This way you can have a scene with about 30 or 40 objects in it. Not 10000 different objects, all nested in Groups, Layers or Families, then grouped inside other stuff, then grouped again. Max hates groups, it slows it right down. Proxies too.

I hope some of this helped. I hate groups, proxies or scenes that are badly optimised, with sub 5fps in the viewport when trying to work... or massive preload times in renders.

Here is the script I use to Attach all by same Material btw:
https://www.scriptspot.com/3ds-max/scripts/attach-by-same-material
It's really quick too.

:Edit: This AutoDesk 3DSMax routine is also very handy:
https://help.autodesk.com/view/3DSMAX/2023/ENU/?guid=GUID-7D388AEB-E42D-480E-805E-4312862461E7

There are also a lot of scripting ways to select all objects of a certain class, volume, or shape.
Maxscripting is very powerful.
The Darkside awaits:
https://www.scriptspot.com/3ds-max/scripts/object-replacer-0

I hope you found some of this helpful 🙂
Regards,

Re: 3ds max fbx file link: how to preserve instances?

zvsmail — Sat, 20 May 2023 00:34:57 GMT

FBX format seems to support instancing, more to say 3Ds Max supports instances export to FBX from version 2013 which is clearly stated with reference:

https://download.autodesk.com/us/fbx/2013/3ds_Max_FBX_Plug-in_Help/index.html?url=files/GUID-CC2FF358-632A-4E93-8FA4-493E340B28CD.htm,topicNumber=d30e2305

What you propose could make sense if instanced geometry arrived as a separate objects. The problem is that whatever link profile you select, 3D max combines objects together as a single mesh by material or Revit Category or whatever. What is the most annoying is when selecting Do Not Combine profile - instanced parts are attached together. So let's say you have 1000 identical roofs attached together, or 1000 entry door handles attached in one mesh, and so on with every instanced element. Automation is impossible with such source.

Anyway, setting up houses by hand is not an option as a master plan definitely going to be changed with the next iteration.

Re: 3ds max fbx file link: how to preserve instances?

darawork — Sat, 20 May 2023 00:58:52 GMT

Thanks for the info. Handy. If for any reason you ever need to detach by element, I use STR TOOLS: https://www.scriptspot.com/3ds-max/scripts/strtools

Or: https://www.scriptspot.com/3ds-max/scripts/detach-by-material-id

Just helpful sometimes too. You can automate a lot of these routines to free shortcut keys, buttons or macros. Max isn't perfect, but it still allows users to make it easier on themselves. 🙂

Regards,

Re: 3ds max fbx file link: how to preserve instances?

domo.spaji — Sat, 20 May 2023 12:53:22 GMT

Max will preserve instances from imported FBX.

Re: 3ds max fbx file link: how to preserve instances?

darawork — Sat, 20 May 2023 14:31:31 GMT

Doh

Re: 3ds max fbx file link: how to preserve instances?

zvsmail — Sun, 21 May 2023 17:25:16 GMT

That's true. However, my question was regarding LINK import.