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bittleralain01
05-06-2009, 12:34 PM
Hi all,
I try a simple scene test to use ZBrush displacement...
I've got a problem between ZBrush and Lightwave, I do all the process to get a displacement map resolution 4096, but when i use this map in layout there is so much details lost(displacement node), i don't know what to do? How to get the small details without exploding the number of polygons?
Here is the preview in LW and the other in Zbrush.
Any ideas?

Cohen
05-06-2009, 12:56 PM
I have to ask the obvious first: Did you export your map as a 16bit tiff image? If so, then it must be the subdivision level from which you baked your map at in zbrush. What I normally do is bake from a low level (subdivision level 2-3 for example) and use that map in the vector displacement editor. I then bake another map in zbrush at a higher subdivision level (at around sub-d level 5-6 or so to extract the finer details), and plug that into the objects displacement and bump channels in its shader tree, and turn on bump displacement around 1-15mm depending how it looks (given its built to some real world scale). Anyways, thats usually how i do it, there are other ways too...

Cohen
05-06-2009, 01:14 PM
Here's a snapshot on what I mean.

cresshead
05-06-2009, 01:20 PM
http://www.newtek.com/forums/attachment.php?attachmentid=73148&d=1241460586

simple as that!:D

also do not use a psd for displacement as your polys WILL explode

bittleralain01
05-06-2009, 02:58 PM
That is what i am doing, i am using ZBrush 3.1...
I export displacement map as 16bit Tiff, and normal map at 32bit Tiff(don't know how to export it at 16 bits and normal map seams rotated 180, i don't arrive to use it well, please help)
I have tried another example i post here, but there is less detail in ZBrush, the result is better, but there is loss, sure...

if i want to do something with the level below, maybe i need not to loose details ;)

http://www.renderosity.com/mod/gallery/index.php?image_id=1852696&page=4#comments


Alain

bobakabob
05-06-2009, 04:42 PM
Combine displacement with a normal map and the details will show without the poly count going stratospheric.

Tranimatronic
05-06-2009, 04:50 PM
what did you set your subdivision level to in lightwave ?
it doesnt correspond to the zbrush subD level. As a general guide for level 6 in zbrush I use level 14-20 in Lightwave depending on how close to the camera I get......

Cohen
05-06-2009, 05:40 PM
With respect to these being height maps and only 1k in size, lightwave is 99.9% on the money. I could to tweak this more to get the exact depth, but this is just a quick test. As Tranimatronic mentioned, your results may be due to user error if you are not using the proper base subdivision level. General rule of thumb is to bake your main displacement map and displace the geometry at the same cage level, simply because you are using height maps (This essentially fixes all base polygon normals to be facing the direction they are to be displaced). Now if only zbrush could export high precision vector maps...

cresshead
05-06-2009, 07:22 PM
also turn OFF pixel blending as the proton vid shows too.

bittleralain01
05-07-2009, 07:13 AM
Thanks for your patience but i don't solve my problem.
Cohen or anyone can you zip and post an exemple(very simple) zbrush and LW and the low map(with normals)?
I need to study it, please

cresshead
05-07-2009, 08:55 AM
do you want scooter?

http://www.newtek.com/forums/attachment.php?attachmentid=73149&d=1241461614

http://www.newtek.com/forums/attachment.php?attachmentid=73139&d=1241454243

bittleralain01
05-08-2009, 09:05 AM
Yes it 's a good idea, post it
just one question why there is so many people that use cat or dog as icon?

cresshead
05-08-2009, 09:10 AM
Yes it 's a good idea, post it
just one question why there is so many people that use cat or dog as icon?


i'll upload later after coming back from "spar trek"

re cats....it's a lightwave thing...:D