ZBrushCentral

3.5R3 (Import/export Scale issues with subtools and transpose master)

ZBrush Usage Questions
#81

You guys have probably figured out or noticed this already, but I’ll
say what I have discovered in case someone new to this thread has
skipped to this page or whatever lol!

I found that having the scale 1 offset 0,0,0 for all your subtools will affect
the amount of distance you can drag your geo around with the move tool.
Some people have only been able to pull their geo by millimeters! (from
what I’ve read in other threads)

This sucks because you want to keep things the same scale and offset for
maya, softimage, max, lightwave whatever to keep it logical right? With a
scale 1 offset 0,0,0 and using 1cm = 1 unit (place your fav 3d package
here) you could run into this problem.

So what I did once I followed the instructions here to get my
character/scene to the right scale 1 0,0,0. I found that the move tool
looses its “drag distance strength”, since my fav unit is cm. To solve this I
created a large 1000by1000by1000 box centered at 0,0,0 in Maya and
imported all my subtools to that large cube in Zbrush. This should change
the scale value to 500.000 offset 0,0,0. Instead its 499.999969 offset
0,0,0. So what sort of weird math is going on there to get a number thats 6
decimal places out!!! :lol:! I mean I am getting finnicky about precision for
such an infintismal number, but makes me even more suspicious of the
coding around this whole scale, offset issue. Try making a cube that big
and bring it into Zbrush and look at that number (I do it for days on end,
and by the looks so does everyone else here in this thread :lol:)

There must be a certain available sculpting yield that ZBrush has based on
the scale of your object. :rolleyes:

The only reason I hit this problem is because I use 1 maya unit = 1cm. I’m
185cm tall and I base my characters height off that, by looking at my
character from that height in other 3d packages. SOOOO what I should
really be doing is making my units 1 maya unit = 1 metre, to avoid the
sculpting prob in ZBrush. But really should I have to do that when ZBrush
has the issue? :confused:

After using my scale at 499,999969 and offset 0,0,0 and having fun
sculpting and zoning out, I take the scale back to 1 keep offset at 0,0,0
and export that object for refining in Maya. Problem solved sorta…
…sometimes I forget to put it back and get a mess again. But this workflow
works well for me.

I’ll post up more discoveries if I find any.

#82

Is it just me, or does this bug occurs when importing when the default sphere is on ?? (the sphere that adds to zbrush startup, not one you manually add)

A collegue suggested this, and ever since I removed that sphere from startup, and switch to one of the other brushes (like simplebrush) before importing … things seem to work quite better now.

Hopefully not a product of my imagination …

#83

Svartberg, no its not a product of your imagination…

it really will mess up with the scale (make the model a lot bigger) if you import your OBJ having the startup polysphere selected. Thats ****ing stupid, as other many stuff. I always switch to simplebrush before import something right after open Zbrush.

but scale issue still happens between max and zbrush in diferent situations. I gave up to find a answer or solution, it seems totaly random.

#84

I ran into this issue again. This time, I exported a subtool as reference to make an additional piece for my character. I made the piece, imported, appended and it was huge and offset. I appended the new geometry to my original tool and it was tiny and offset.

#85

I think that the export section of the tool palette was supposed to be
independant for each of your subtools. But only partial sections of the
code in that export section have been changed to be per subtool (totally
guessing of course). You can tell that something is messed up in there because
when you start inputting values for each of your subtools to get them back
to the original state, you will notice the number change just by clicking on it.

for example You go through all of your subtools one by one checking the export values. They are different. Some are the same and some are not. So you change the top subtool to the correct values. Every subtool below displays the new values. BUT thats just it! they are only displaying the new values they don't actually take on those new values. Which means you have to go one by one changing the values. When you do start fixing them you might notice another weird number pop up in the scale textbox when you click it. It might change from 499.999969 to 14.45673 just by clicking on it. Say I had 15-20 subtools with messed up scale/offset. Each subtool needs you to do 6 actions per subtool in order to fix my model as a whole: click the export section. type in scale, press tab. type in x offset, press tab. type in y offset, press tab. type in z offset, press tab. press the "down arrow".

Thats 6 actions x 20 subtools = 120 times I have to input correct values!

What about those impressive models on here that must have 50-100
subtools! LOL!!! Thats a lot of time taken up for that artist, putting in those values.

Sounds like a job for da da da da da da Autohotkey!

I find that extraordinarily horrible to have to do this randomly throughout your project.
#86

In the subtool master plugin, there is an option to reset the scale to 1. This makes all values set to one and export is as should be.

#87

The problem you are then faced with is when you import meshes and append to this tool their scale and offset will not match.

Someone pointed out in another thread that saving a tool with polygons hidden sets the export scale and offset values to scale=0 x=0 y=0 z=0. This turned out to be where the problem is cropping up for me with every project.

#88

After a bit more experimenting with this issue, I found that only hiding geometry in the top subtool matters to avoid scale and offset getting zero’d out. So a simple workaround I did was to make the top subtool a tiny triangle that is there just so I don’t have to worry about this happening.

#89

mucky_wet_noodle - Partially hidden top subtool causing the problem
eh?! Great find! I thought it had something to do with cloning, duplicating or
appending (which it could possibly still have something to do with it).

Aberrant - It would be good if it put in other numbers for all your subtools
other than 1,0,0,0 because just like what mucky_wet_noodle says you will
have importing issues with those values.

For every different sized piece of geometry you bring into Zbrush gets
different values in your export section. They are consistent with each piece
coming in. I THINK its when you start merging pieces together that you
could run into problems. I’m still not sure where this problem comes from,
but its good to see that mucky_wet_noodle has found a lead. Infact that
makes a lot of sense because in Zbrush’s mind the object has changed in
size!

It would be good if scale/offset remained at 1,0,0,0! If Zbrush needs to
scale things for it to calculate so many polygons, then do it behind the
scenes.

#90

removed

#91

Hey guys, Some really helpful advice in here. And some of it worked for me but not 100%. I would say 90%.

As a professional in the game industry this can be incredibly frustrating for myself and others on the team. And has cost us a lot of time.

Originally the problem was that my sculpt did not match up with the skeleton anymore in 3dmax when originally everything was just fine. So I am guessing during the sculpting stage some things got changed. Okay… Well, now knowing how things work in Zbrush and the ways to solve the problem I go ahead and give that a shot.

and… IT WORKS! almost…

Now the model is no longer tiny, but instead is 1.5 times bigger than the rig. After I got the correct scale and translation numbers off the correct mesh. Here was my process to be clear:

  1. Fresh restart of Zbrush

  2. Selected SimpleBrush and Import correct mesh with correct scale

  3. Select SimpleBrush again (just to be safe) and load the problem Ztool

  4. Copy over manually all translation and scale numbers FROM corrent mesh, to the problem Ztool ( I do this for the top tool only because I noticed it changes the scale for all other subtools.)

  5. I then save the problem tool out as a new Ztool (DID NOT EXPORT because there are too many darn subtools).

  6. Restart Zbrush to have a clean slate to work in.

  7. Load the problem Ztool with the new export numbers. And then import the correct mesh (by selecting SimpleBrush and then importing).

  8. Append correct mesh into problem Ztool to check if they match

AND…

still wrong.

I’ve tried many many other techniques, some mentioned and others I tried on my own. Nothin seems to work. So for now I plan on having two versions of the in game low poly mesh. One for baking the normals and AO and then another that is scaled up in 3dMax and manually fit to the animator’s rig… NOT fun to worry about this kind of thing…

Any updates on this issue would be amazing. And any help would be greatly appreciated! Thanks!

  • KP
#92

Guys, upon creation of a Ztool from an OBJ the first time, type the numbers in a text document, save the text document with your Ztools.
When Zbrush magically looses the info, type it back in from the text document.

Works 100% of the time.

#93

Hello

Here is a plug-in that will allow you to copy and paste your values. Plus you can load the original obj to get the values.

Hope this helps.

Paul

#94

Has anyone had the issue of doing retopo. Exporting the new topo. Tweaking it in an external app like maya. Reimporting the new topo and selecting it as the new topo only too have it either bigger or moved? Freakin headache.

I found by chance. That if you do a project all on level one on the model. Then delete the highres untopologized model and select the newly projected topology in your zsphere edit topo, its back to normal. Wow.

She sells, sea shells, by the sea shore…

Nevermind. It doesn’t work:/ was a freak happening.

#95

KPtoons - You have do type in those values for all your subtools, not just the
top one. I’d check out the little program gabo1991 has made

gabo1991 - Well done on making that program. I’ll be checking that out later
for sure.

brettSinclair - I have had that problem and the way how I got around it was
to bring in a cube onebyonebyone (shouldnt matter). Append the “edit
topology” object to that cube (and have it selected). import another
onebyonebyone cube, and append the “rigging” topology to that one (and
have it selected). Then click on a zsphere and do your regular re-topology
workflow. And it should line up sweet. That export problem gets its fingers
into everything MAN!!! YAARRRRRGGHHH!!!

#96

Hey Sadamhu, Its seems my method actually did work. I just forgot too do somethings when i added the new topo mesh. Lol. But jeez. This is a nightmare. I really hope they make this easier and better. 3dcoat has an amazing retopo tool set. I just don’t own a licence for it :P.

#97

Hello

Actually Marcus Burgess wrote that plug-in not me. :slight_smile: It should help though.

Paul

#98

Was having similar issues in my ZBrush > Max 2011 workflow with OBJs - have read the entire thread and believe I have tried all of these work arounds before without consistent positive results, but will give it another go with some of my older models to test.

What I did was finally just export everything at a level 1 - reset all axis inside of Max - reimport and then resproject all of my levels up to 4 since I was only that far on my 19 subtools - so far I have been using the resetscale button and have had no further issues - /fingers crossed.

#99

OOh sorry Paul I forgot to reply to you about how I got on with that script,
you gave me the link to. I have had about a 15-20 min play with it and found
its not working for me. I thought I knew how to use it, but I guess I don’t fully
understand the whole scale bug problem to be able to utilize the script, when
it seems self-explanitory. Also I have adapted to the problem and tried
working around it by exporting only what I need to Maya for reference no
matter what the scale (pain in the ass…). occasionally when I import I get
screwed scales. But I haven’t really had much time to have a good poke
around with the script. When I get some more time I’ll check it out.

#100

Sadam

The bug is some subtools are losing their values in the Export Sub-Palette. Now the thing to understand is that it will be very rare for your tools to have values like this:

Scale = 1
Offset X = 0
Offset Y = 0
Offset z = 0

It is more common to have crazy values like: (these are just made up numbers. Every tool will have different numbers)

Scale = 34.6879
Offset X = 2.123
Offset Y = -1.9080
Offset Z =0.9898

This is were the bug comes into play. If you have a tool with lets say 5 subtools on it. All of the Scale and Offsets values should be exactly the same like this example.

Scale = 34.6879
Offset X = 2.123
Offset Y = -1.9080
Offset Z =0.9898

What will happen is some of your subtools for a reason will change back to:

Scale = 1
Offset X = 0
Offset Y = 0
Offset z = 0

The plug-in will allow you to copy & paste the correct values which are:

Scale = 34.6879
Offset X = 2.123
Offset Y = -1.9080
Offset Z =0.9898

into the ones that have these values

Scale = 1
Offset X = 0
Offset Y = 0
Offset z = 0

Just remember all subtools should have the exact Scale and Offset values.

Hopefully this helps.

Paul