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G3D
02-14-2005, 03:04 PM
I have been experimenting with ZBrush and Lightwave with very poor results. I have downloaded and successfuly rendered the two OBJ files that Pixologic provides, so I know that at least sometimes this can work.

In addition to Lightwave I am using Maya. In both Lightwave and Maya, the OBJs and Tiff files that ZBrush writes result in renders that look perfect in some areas and have inexplicable rips and tears in others. The rips and tears happen in the exact same places on the imported OBJs in Lightwave and Maya.

I have posted a long thread tht documents this at ZBrushCentral, but the moderators there have elected to delete threads that might indicate there could be an issue with ZBrush.
So I am posting this not to be negative, but to see if anyone has developed a workflow with Lightwave (or Maya) that can get a model(called a "Tool" in ZBrush) to render properly in an external package. I posted this same question at CGTalk in the Maya forum; over 100 people viewed the post, yet no one has responded. This indicates to me that it must be difficult to do properly.

I'm also looking for information a little more detailed than a link to Pixolgic's website or the test files mentioned above.

So if you are a ZBrush user and have managed to get something out of that program and into Lightwave or any other 3d app and have gotten acceptable results, please post.

Rory_L
02-14-2005, 10:02 PM
Have you checked out Glen Southern`s tutorial in the ZB Practical Guide? It`s in the ZB and Other Software section, under ZB and LW. He shows how he takes an alien from ZB to LW.

There was a ZB to LW thread here a while back. you should have a search for it.

Cheers,

R

G3D
02-14-2005, 10:26 PM
I'm hoping for something a little more detailed than that.

Intuition
02-24-2005, 09:59 AM
I have been delving into Z-Brush for about a month now and I realize how many crucial steps are skipped in some tutorials in ZB -to- LW.

Z-Brush Practical guide has a LW section that is more like a torture then tutorial.

You see all the neat stuff but have no way of knowing how to do it.

This tutorial is pretty good but should take you through the sections of Z-Brush better. I know from using Z-Brush a bit where to find all the buttons you need but if you havent used it and havent placed the TOOLS in the left like he has you may not find the buttons you need.

http://www.stevewarner.com/Tutorials/zBrush/zBrushTut.html

What someone needs to do is take Steves tutorial and add a few more interim steps so people know where to find all of the tools and texture export buttons you need.

If you look at the pics you can figure it out but it should be in the text description as well.

Like in modeler they say CREATE>SPHERE>NUMERIC so you know what tab a certain tool is under.

Many tuts assume you know Z-Brush very well, which alot of people would learn it if they knew getting in and out of it better, yet many people get discouraged when the process seems complicated, when it isn't.

Also they need to point to the needed plug ins for 16bit Tiffs and lynx's normal displacement or Zwave.

Thunderb
02-25-2005, 11:56 AM
I am writing this with the hope you guys already know about the basics of Zbrush-Lightwave and the plugins needed

I use Lightwave and Zbrush daily. You can easily figure out a good workflow between them just experiment. I have had numerous problems though, :mad: hours of playing around. You need the right plugins which are listed on the Zbrush forum. The only major things to take into account are that when you go down to your lowest mesh division ( I turn on Cage and export I dont bother with the Morph stuff ) Then turn on DPSubPix to 1-2 DPRES of 2048 or whatever then create displacement map, wait......then always flip the image vertically then export as a .tiff.

Then in Lightwave i have found that you need a really high mesh setting to get good results, set your Displacement to the required size. Leave Vertex size. Luminance centre to 50% and thats it really combined with the addition of the map applied into the bump channel.


I have read elsewhere in the zbrush forums that apparently Zbrush doesnt like open meshes and sometimes errors are produced on the exported maps like around the eyes on a head for example. Sadly I cant attach an example file (lws) because the tiffs are hooooge..... hope this helps a little. :p

peteb
03-01-2005, 03:42 PM
The reason you get tears in certain places in your mesh is because Lightwave doesn't support sub pixel displacments and can't cope with really severe differences in the hight of the mesh in fine detail areas.
The way I solve this is to export a higher level mesh from Z-brush. So instead of exporting the base level 1 mesh export 2 or even 3. The only downside to this is that you're now dealing with a more dense mesh and if you're animating this may slow you down.

Pete B

G3D
03-01-2005, 04:12 PM
The reason you get tears in certain places in your mesh is because Lightwave doesn't support sub pixel displacments and can't cope with really severe differences in the hight of the mesh in fine detail areas.
The way I solve this is to export a higher level mesh from Z-brush. So instead of exporting the base level 1 mesh export 2 or even 3. The only downside to this is that you're now dealing with a more dense mesh and if you're animating this may slow you down.

Pete B

Maybe you didn't see all of my original post. I also did renders with Maya and mental Ray and got exactly the same results. Below is a side by side comparison. I didn't need to
render out the object once I loaded and set it up in LW since it was obvious what was going to happen.

peteb
03-02-2005, 03:28 AM
Oh right sorry, yeah I didn't see those pics. I know the pinch tool can cause problems, do you know if you used that in that area?

Pete B

G3D
03-02-2005, 09:54 AM
...I did some messing around and now I think its some combination of steps that have the same effect as the pinch tool.
My workaround is to save the tool as a new version after each session, and at the end of each session export a tiff and try it out in Maya/MR.

When I have a clearer picture of whats up, I'll post the info here(and atZBrushCentral)

Thanks ofr your help.

peteb
03-02-2005, 09:59 AM
Hmmm strange. It's weird how in Maya it's so much worse.

Yeah let me know if you find a solution.


Pete B

G3D
03-02-2005, 10:02 AM
Since Mental Ray does sub-pixel displacement it should benefit the errors as much as the intended displacements.

CB_3D
03-06-2005, 11:39 AM
Ok, maybe iīm better off posting this here :p


I am having some problems with normal displacement. Apart from he correct displacement the whole mesh is diplaced. Anyone run into the same?

G3D
03-06-2005, 01:04 PM
When you're in ZBrush, you drop down to a division level of 1 and generate the displacement after either switching to your stored morph target or re-loading the original OBJ you imported before you started sculpting. If you don't do either of those steps and generate from the sculpted object at level one, you can get results like that.

CB_3D
03-06-2005, 02:17 PM
Nope,did both things. Still getting the same result. Confused.

G3D
03-06-2005, 02:19 PM
that when modeling in ZB you accidentally used the move tool on the entire tool?

CB_3D
03-06-2005, 02:52 PM
Thatīs not the problem,neither. I repearted the same several times using only the paint tool. Happens always.

And itīs not because of the holes in the mesh. I made the same test with a closed sphere and the same happens.



____________________________________________

CB_3D
03-06-2005, 08:32 PM
Well,i am narrowing it down. This is only visible with cages visible. Now i use a noise to displace,no UV stuff at all. Again,this is the free Normaldisplacement plug.

CB_3D
03-06-2005, 08:43 PM
And now the same with LWīs Normal Displacement. Here the error doesnīt occur,but itīs so sluggish and unpredictable with UVs that itīs not of use.

Conclusion: Itīs a minor bug in the free and generally much better NormalDisplacement.

CB_3D
03-06-2005, 08:48 PM
Itīs just the visual representation of the cage that shifts, not the object itself.OpenGL error or something,no big deal!

Man,why is that native Displacer so slow and bad???