Zbrush displacement issues
 

I know this is a maya forum so sorry if I shouldn't post this here but since some people here use zbrush I thought I'd try asking here. I've looked everywhere for help for my issue but it's not working none of the tutorials are helping. I've posted in another forum but have had no luck with replies, hopefully someone somewhere can help me. Here is a very descriptive description (hopefully descriptive enough)


-I created a underwater sea creature in Maya 09. (yes this thing again, it's proven to give me many difficulties)
-I laid out the U Vs in the 0-1 coordinates since that's how I always lay out U Vs that wasn't anything new to me.
-I then selected object and exported as an OBJ
-Imported into zBrush 3.1 and I sculpted the model, up to 5 subdivisions (can't really figure out why I can't get more than that but it's ok because it's all I needed for this model)

now every time I try to export a displacement map I get just a gray 2048x2048, no difference in gray to white or black, just a flat gray color that is useless to me. I've followed many peoples tutorials and suggestions and nothing seems to work. The only thing I can think of is when it's creating the displacement map it says "Creating Tile.0" and I'm guessing that it should say Creating Til.1 but it's not it always says 0, and I have no idea how to fix this if that is the issue

Here are my settings if they help or not

Mutli Displacement 3 Menu:
Udim: 0
InitialFileIndex: 1001
MaxMapSize: 2048
MapSizeAdjustmen: 0
DpSubPix: 3
Border: 8
Export Option:
R32 with Quick Code: DE-LBEK-EAEAEA-R32

Under the Texture option I clicked EnableUV

Under the Displacement:
DPSubPix: 3
DPRes: 2048
I've tried with Adaptive and SmoothUV on and off, and a variation of one being on and one being off

Under Polygroups I have the Uv Groups selected.

Under Geometry I bring it down to SDiv 1 and try to export, I've tried it on 4 and on 5 and I can't get it to export either of those.

I don't need this model to bring back into Maya I just need the displacement map and I just can't get it to work. Any help or ideas would be greatly appreciated

I feel like it has something to do with the Creating Tile:0 not being 1 but I don't know anything about zBrush and this is the first time I've ever used it so I could be completely wrong.

I also never did anything with Morph Target but don't know if this matters or not..

Anyway if anyone needs anymore info on my scene I will be glad to give you the answers for the help.

When you add a displacement to maya you need to tweak some of the channels in the attributes since zbrush reads grey differently than maya. Also when you are exporting your displacement from zbrush you want to be on the lowest subd of the mesh


its a good idea to use morph target when you import the geometry just so you know the displacement will fit nicely into the mesh that you import when you go to import it back to maya.

Thanks for the help but when I take it into maya and place it in the displacement file for a blinn and I adjust the approximation editor it still comes out as a completely flat object. I'm getting nothing from creating the displacement map, wait 17 minutes to create it and another 3 for a render in mental ray where the displacement has no affect.

I did not do a morph target would this make the grayscale displacement be all gray with nothing on it? Adjusting it in photoshop either makes it white or black not segments where it should be different scales of gray like it should have.

Oh and I didn't create any layers either, is this needed? I don't have an actual maya zbrush pipeline dvd from digital tutors or anything, I'm going off of stuff I found on youtube and searching in google. Apparently I did something wrong somewhere and it's not working at all.

well I reimported the model fresh start and created a morph target and did a quick little bit of sculpting and did a quick displacement map and it seemed to work once I had the morph target, who would have thought, unfortunately I have to start clean in order for this to work, I'm just happy I got it.

Mike

its not always necessary to create a blendshape before doing work in ZB, but if its good for the workflow then fine.

With regards to the map tiling, its sounding like you have had an exploded uv in Zbrush. I had this trouble in the week on a 12million poly model(In production) it took me a while to figure it out. So every time I had to make the dismap zb would recalculate the tile, it ended up having 47 tile maps which is pretty useless at the end of the day. You only need have 1 tile which would be your 0 -1 uv. You can use the 'check mesh info' command under the Multidis3 menu set. It should just display 1 setting.

also try this code; de-hbek-eaeaea-r32

this will generate a 16bit dismap and not a 32bit as your previous setting. Also worth noting, IF you are to open these in PS to edit make sure color management is OFF other wise all the bit bit depth will go to hell and screw the map.


always generate the map at the lowest res as it wont calculate properly. As for using Adaptive or Subpix, thats a matter of choice at the end of the day as to whatt works best for you. I use adaptive as its faster and I get very good results. If you're using subpix dont go any higher than 2. And lastly Intensity is usually set to 1 and mode should be 'on' to create the Dismap and not a standard bump.

hope this helps

Jay

Jay
Thanks for the help I appreciate it, I tried screwing around with the finished model a little bit more after reading this and still came up with absolutely nothing. So I'm guessing when I imported the model and did all types of clicking around and pressing buttons (it was my first time really using zBrush for anything other than to screw around) I messed something up in there that just didn't work. I will be re-importing my .obj and creating a morph target then subdividing and then modeling in order to make this work like my little tests did. I appreciate the time and the info which will be helpful and maybe I'll screw around a bit more before I actually get into sculpting this creature.

Thanks again

edit: Is there anything else I need to export other than displacements for the ultimate realism of these bumps and scrapes and stuff I'm going to be putting on my creature? Should I learn SSS Shading with this? Or is that a whole different thing?

get a normal map out too for the finer details.

Also sss is a bit of a mission if you arent familiar with it, so I'd head over to 'ahem' gnomon for the sss tute, its actually very good

J

thanks again for your help Jay, I will look into SSS see if it's worth it (I am going for a realistic skin look to this creature so it might be unless it's only good for humans) and I will look up how to get the normal map from zBrush next.