FBX Export Scale Headache!

[zero-13]

I swear I remember a time (Not GOZ, just FBX plugin) when I would import an FBX into ZBrush from 3ds Max and export an FBX and the scale the FBX it started out in would be maintained, none of this 32.666% smaller nonsense?

Please, for the love of all that is good in the world, why should any other behavior be expected?

I know ZBrush works better scaling to whatever mathematical scale it needs, but how about some consideration for quality of life or maybe just plain old convenience and end user logic aka expected behavior?

Why can we not get the invisible magic of maintaining initial scale to happen in the background and just work?

It’s beyond frustrating dealing with and memorizing thousands of little technical quirks when you just need to get things done and have things work in a slightly logical and expected way.

IRL, If I move a chair to another building I would never expect said chair to suddenly be a different size once I bring it back the building it started out in.

So why not make this frustration go away once and for all?

Is maintaining native imported scale really a technical impossibility or obstacle that simply cannot be surmounted?

Please!

[Spyndel]

Hello!

Sorry you’re having some trouble!

First, I’d like to just explain that these are the community forums, where other Zbrush users like yourself do their best to answer questions for other users. We don’t develop the program. Feature requests should be sent to Pixologic directly via support ticket, tied to your registered copy of the program. Otherwise your feedback is likely to be missed by anyone who actually develops the program. The only thing a rant here can accomplish, is to potentially drive away another user who might have otherwise had the answer to your question. So consider how your time is best spent.

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Most import /export scale issues involving zbrush come from misunderstanding the way the export scale slider works, and improper import procedure. Once you understand the moving parts, it becomes easier to figure out where the process might be getting fouled up.

When properly imported by default (no tool selected), or onto an active tool with an export scale factor of zero (the default polymesh 3d star in the tool menu is commonly used as an import target for this reason), Zbrush will auto scale and auto center the mesh to be useable in Zbrush, and record the values necessary to restore it to its original size and position upon export in that menu.

If the program didn’t do this, the imported mesh may very well be unusable. That’s because the effective worldspace in Zbrush is finite, and many tools–the reasons you’d want to work on a mesh in Zbrush in the first place–will simply not work reliably on a mesh that is abnormally small or large, or off-center. Zbrush’s worldspace is very deliberate, and is what makes it possible to do the things you’d want to use Zbrush for.

The “sweet spot”, where most tools perform as expected is in the ballpark of a Tool > Geometry > Size > XYZ size of 2. This video explains some of the reasons why. When imported into a tool with an Export Scale factor of zero, it will be scaled to hit this size, and the value to restore it upon export recorded in the export menu.As long as theses values aren’t changed, or the mesh’s scale isn’t changed inside of zbrush, the mesh will be exported at its original size.

You could eliminate the auto scaling by importing onto an active tool with an export scale factor of 1 (100%). This means the mesh will now be at 100% of its import size in Zbrush, and export at 100%. All this will achieve is to force you to work on a mesh that may perform poorly in Zbrush.

Most of the time this process is seamless. Where users run into trouble is when they import tools inconsistently into tools with different scale factors, or start changing these values thinking they need to restore the size. They may also fail to realize that their target program also probably has settings that may influence the scale and cause import/export problems.

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This is how it works with OBJ export at any rate, which has been developed for years and is pretty solid. FBX support is newer. A quick test here indicates it’s working the same way, but it’s not inconceivable that there could be a bug. Understanding the way the system works, if you think you have identified a place where FBX export is not performing as expected, and can reproduce this, that needs to be reported to Pixologic Support. All bugs and technical issues need to be reported to Support, not the community forums.

Good luck!

[zero-13]

I think my confusion posting here and the fact that I’m not on the forums hardly ever is the labeling of “ZBrush Help & Support”.

It sounds like potentially the right place to bring up and discuss ZBrush issues or problems, hence the help part, and / or assistance with those issues or problems hence the support part.

I guess the clarity of my frustration is coming through, as planned, because it is indeed frustrating to have an ongoing issue that no other applications you use exhibit and no definitive solution can be found but this was definitely not intended to be a rant.

It’s just an actual issue that I’ll concede was not wrapped in a gossamer blanket of delicate softness but, it’s also pretty mild and I can’t imagine anyone getting personally sad, or getting an emotional bruised knee, nothing really “sharp” in there, all child safe parts as far as I can tell.

The scaling issue is peppered throughout the internet by various people, in various locations, but no solution to be had, as those issues apparently cannot be aggregated and discussed by the community in one place otherwise the forum police and Pixologic PR will come crashing down on you and sweep it away lol, (just a playful jab, don’t get all misty or peppery please ) for fear of what, I don’t really know.

I also fail to see how on earth by discussing an issue among the community, that might identify other users with a similar issue and potentially lead to a solution, could possibly drive away someone with an answer?

I just give people a ton of credit for not being graham crackers, and having the fortitude of spirit to understand and relate to another persons reasonable frustrations towards an ongoing issue.

I’m not an angel nor a machine, non of us are, I think most people can handle what I originally posted without falling apart or avoid not being helpful solely out of some imagined judgmental control bias and / or spite, at least I would hope so.

Then again maybe I’m wrong?

Thanks?

[Stephen_Layne_Studio]

ZBrush scaling issues are indeed exasperating. I had a software engineer who was familiar with this try to explain it to me and I tried to keep my eyes from crossing. I’m still going with importing a mesh from, in my case, Blender, in order to keep a sense of ‘real size’.

But I’m writing here primarily to thank you for a very entertaining response. Made my day.
I cannot help but envy your articulative prowess and creative illustration.