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lordofuo
11-07-2009, 06:17 PM
Is there a way to make a working displacement map with a basemesh you make with ZSpheres? I know you have to make a UV map, but if the basemesh is really complicated, that can be time-consuming.. (if it's necessary i'll do it, though)

isnt there a feature in ZBrush that allows you to create a UV map automatically?

basically, Im wondering how you can do the following:

1.) create a basemesh in ZSpheres
2.) Make a working UV Map for that basemesh in ZBrush
3.) sculpt in all the details.
4.) export a working displacement map
5.) import the obj basemesh in 3DS max
6.) apply the map using the VrayDisplacementModifier
7.) it works!

if tried various things, and the only one that doesnt make the mesh explode is doing the following:

1.) made a sphere in ZBrush
2.) exported as OBJ, then imported into max
3.) unwrapped the coordinates. (this was easy since it was a sphere, but an extremely complicated ZSphere basemesh could give someone a heartattack...)
4.) export the unwrapped version and imported into ZBrush
5.) sculpted various details with high poly levels.
6.) exported a 16bit displacement map
7.) imported the unwrapped version in 3DSmax
8.) added the vraydisplace, then added the map.
9.) it works perfectly!


other ways, not so much...

got any pages or advice you can point me to?

Thanks

Alex :beer:

mattlev6
11-07-2009, 06:51 PM
yup, just do your thing with the zspheres, convert it to a polymesh, then go to Tool>Texture>AUVTiles. and the nice thing is you can do it at any point, even after you've given it a paint job. keep in mind, though, that you won't be able to work with the resulting uv map in photoshop or anything like that, because it just creates a grid of squares that makes no sense to the user. but if you're doing your displacement, normal, specular, etc.. maps in zbrush straight from the tool, you'll be good to go. Also remember that you'll want to do this at the lowest subdivision level for your tool, so just finish your model, move the slider down to subdiv 1, click AUVTiles, move the slider back up.
hope this helps!

lordofuo
11-08-2009, 06:06 PM
Thanks for the advice!

I did what you said, and the resulting map makes my mesh bloat up when using it in the vraydisplacementmodifier. :sad:

i must be doing something wrong:

I finished a model, and did the following:

-went to the lowest subD level, and hit AUVtiles.
- exported the lowest level as an OBJ.
- created and exported a displacement map.
- imported the OBJ in max
- imported the displacement map into vray displacemod
-rendered.
- the resulting render looks pixelated, faceted, and "bloated". like the mesh just exploded or something...

any ideas?

Thanks for the help!!

Alex :wavey:

mattlev6
11-08-2009, 06:15 PM
i use maya, not max, but in my experience, those sorts of issues are not due to the zbrush part of the process. the bloating, for instance, tends to be the result of using improper settings for alpha gain and alpha offset in maya.
if you search some of the tutorial forums at zbrushcentral, i'm sure you can find some in depth info on setting up the max end of things to render the displacement, and more details about all the different settings to use in the displacement exporter in zbrush.

lordofuo
11-09-2009, 02:52 AM
Well, I've tried doing that with both mental ray and vray. Plus i've tried all the different exporting options, etc...

I've even tried it in different versions of Max at a friends house.

Is something wrong with my install of Zbrush?

I mean, i can take a simple object in Max, unwrap it in max, import in in zbrush, detail it, make a displacement map, vray displace it in max, and it renders great... its just the AUVtiles that wont work... But that's exactly what i need for polypainting and stuff.

it's so weird. it looks like it displaces lots of tiles with some of them "exploded" from crossing faces...

If I can figure this out, I'll finally be able to render my sculptures correctly... :hmm:


If you need an example of what is happening, I can post a pic?

Thanks for the help!

Alex

lordofuo
11-10-2009, 03:36 AM
I figured it out! :buttrock: :buttrock: :buttrock: :buttrock:

It looks fantastic with Vray.

Just one thing though, and im sure I can resolve the issue if I play around with it some more:

my model after rendering it looks a bit 'fatter" than it does in zbrush. is this because My displacement value is too high?

if so, is there a way I can set it to displace exactly the same amount it is in zbrush? (just wondering...)

thanks again!

Alex :bounce:

mattlev6
11-10-2009, 04:33 PM
glad you got it working!
i would imagine that the "fatness" is due to one of your settings in max, but since i'm not a max user, i can't really be helpful with that one. again, in maya, it would most likely be the alpha gain and alpha offset that need adjusting, but in max, i don't know.

thev
11-10-2009, 04:56 PM
my model after rendering it looks a bit 'fatter" than it does in zbrush. is this because My displacement value is too high?You may need to adjust the Shift value in VRayDisplacementMod to bring it back to the normal level.

Best regards,
Vlado

lordofuo
11-11-2009, 01:14 PM
Thanks everyone!

@mattlev6:

I looked in the output tab of the tiff file once it was imported into max, and all I saw were ways to set the RGB output and offset levels... Is this the same as the alphas? (or works the same?) I know it has something to do with the displacement modifier... I can set it to be completely bump-map and no displacement, and it looks normal. (with the exception of some features not being as "defined" as they should be. (but they are with the displacement.)

@thev:

I never even though of that... I'll try that as soon as i get back to my workstation. (Im at my colleges library right now. They arent really worth trying to work on... heheh)

Thanks again everyone. I'll post back and let you know if the changing the shift value worked... In fact, i just googled "shift value vray zbrush displacement" and a thread came up on I think Zbrushcentral where a guy used a -4 shift value to get good results...
I might have to play around with it some though, since I think it may be dependant on what scale your object is.

alex

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