Sculpting with UVs and displacements.

[michalis]

Inspired by some zbrush technics of my good friend MealeaYing.
Have a look
Most of all, inspired from the Prometheus movie and specifically from the work of this excellent russian artist.
He's the man behind the 3d rebuilding of the alien ship.
OK, common technics in zbrush but what about blender?

Here's some tests on the following technic. Post yours, let's start a thread on this kind of sculpting.

[michalis]

So, a small tutorial for anyone isn't familiar with the new UV editor and/or baking displacement technics.

1. We build a panel, a relief like thing, it will be our basic pattern.
2. Place a plane in front of it, so not to touch. edit mode/U (for ucs) do UVs on it. Assign a 32bit 2048x2048 black map on it and save this map)
3. We gona bake displacement map selected to active, so. (select the relief first and shift+select your target - the plane)
3a. A 32 bit exr is the appropriate format (very important!)
3b. Under the bake panel, there's a "distance parameter" in blender units. You can see the appropriate distance from the blender grid. No need precision here, just a give a little more than you see.



Save your baked displacement maps as EXR 32 bit.
So far so good.

Now comes the interesting part.
Start a new blender project.

Do a simple clean box modeling. Please avoid details, a few quads can serve well.
Add seams, cut the mesh into a lot of islands, it sounds weird but I'll explain later. (a method to avoid reputation of the mechanical pattern)
Add a subsurf modifier, 3 levels or so.

1. edit mode/ select all UV it. You'll see something like this:


well, it's not what we need. Basically, because we don't need an unstretched texturing (?!). We need a UVmap alligned horizontally, vertically to the mech pattern. When we'll come to real displacement, this will be great, only this. Else you gonna need lot lot of subdivisions up to lot of millions poly.

2. An easy auto way to have aligned UV islands:
2a. select all and ask for reset UVs, this will produce only square islands for every quad of you mesh. Pack UVs then, to have see them.


Now you'll notice, when you resize all these islands a lot, that we're almost there. But not yet.


2b. Check the box under UV editor window...


With this checked, hover over the 3d viewport edit mode, press L and you can select the whole uv island.
What we will do:
Select a quad on a UV island in 3d viewport.
Press L, select the whole island
Press U, unwrap using FollowActiveQuads. / choose Even, not the default length.


You have a nice flow this way and a grouped UV island.


You can start "painting" now, I mean compositing.

It's time to add a displacement modifier, Subsurf up to 6 levels,if you can handle it.
Add the same displ map as bump on the renderer too. Cycles in my case.
Have fun. Please ask for more help, sorry for my english.



EDIT:
Here's some useful tips, found around this thread.
1. You have to use real displacement first. Don't confuse it with displacements of cycles render engine.
http://blenderartists.org/forum/show...=1#post2245974
2. How to handle textures
http://blenderartists.org/forum/show...=1#post2248566
2.b Why you have to use horizontal and vertical objects only when baking displacement maps.
http://blenderartists.org/forum/show...=1#post2560269
3. How to handle foggy effects inside cycles
http://blenderartists.org/forum/show...=1#post2258036
4. How to loops and control the real displacement via weightpainting
http://blenderartists.org/forum/show...=1#post2268060
5. How to add AO map as well
http://blenderartists.org/forum/show...=1#post2299204
6. A cycles baked Displacement and AO map
http://blenderartists.org/forum/show...=1#post2301591
7. How to bake such maps using cycles
http://blenderartists.org/forum/show...=1#post2300569
8. How to control the dynamic range under cycles (displ- map baking)
http://blenderartists.org/forum/show...cements/page34
9. Atom posted these two interesting tutorials
http://blenderartists.org/forum/show...=1#post2358569
http://blenderartists.org/forum/show...=1#post2357814

A video tutorial from me? No
But here's a great one by Oliver Villar
http://www.blendtuts.com/displacement_uvs_sculpt

How to convert all these to a low poly asset with Normalmap support!

[ng-material]

Wow excellent stuff michalis,looking forward to trying it out myself.You did exactly what I thought with uv islands.

hopefully I can try this weekend.

[michalis]

hey thanks.
Here's a EXR displacement 32 bit map to play with.
Maps and UV unwrapping have to be aligned to the real structure of the mesh. Texture stretching doesn't matter in this case. It's the nature of things. Else, we need a so heavy subdivided mesh...
Of course, we can start adding smaller parts on this model, using the same method. Antennas or guns would be nice, I guess.
My last starship like, the Big... something, LOL, counts 400k after subdivisions. 100k looks almost the same. Bump maps do the trick. Because displ map is aligned to the geometry-topology!
Same principles to sculpting (with the exception of SCulptris, dyntopo, or dynamesh ZBrush)
We don't really sculpt on a multires mesh, we displace! Real sculpting produces real new topology.

[tungee]

Whoaaaa! Thanx Michalis !
Could you also share a blend file with a panel so start with??

[tungee]

Whoaaaa! Thanx Michalis !
Could you also share a blend file with a panel so start with??

[michalis]

Whoaaaa, thanks, double post. I appreciate this.
I just posted the displacement map.
I'm not good on imagining such panels. Hey, you can do better.
I guess, a nice drawing on paper could help to realize what elements are needed for such a panel.

[tungee]

Ok Thanks!
I dont know whether my Mac can handle a 6*displacement?!
Will try it nevertheless

[michalis]

hey, 6* displacement means ~400k. A *5 ~100K still looks almost the same. You will add a bump node for fine details.
Avoid smoothed shading. By all means. It's a hard surf sculpting.
BTW I'm also a mc user. (but it's a mac pro)

[Sanctuary]

Playing with this self made pattern in gimp :


for diffuse, bump and displace.
And a subdivided cube (needed a lot more than i thought to get the displacement not ugly, more than 200k faces)


I decided to play with a negative displace value in the texture :


The negative version of the displace reminds me of some electronic circuitry.

A previous test on that other thread


Without displace (only bump+diffuse) :


(all in blender internal, not cycles)

[tungee]

Hey michalis, ididnt get the displacement part work here is a shot from the uv-nmapping:
DO YOU HAVE SOME SCREENSHOTS?

[michalis]

Nice tests Sanctuary!
You need to brake repetition of the pattern. I explained how. I guess so LOL
The UV editor is the key.
You also have to use blender for constructing reliefs, and bake 32 bit maps.
Gimp won't help you except of cropping the edges of the baked exr.
To build your displ pattern is the more time consuming. But you can use it on lot of meshes.
We can build a shared library of such exr files you know.
@tungee
I don't quite understand.
You have to apply a subsurf+displacement modifiers. Don't go through cycles true displacement-experimental mode, please don't!
Right?
After this, go under the texture properties panel and apply the displ map under disp sub menu, there.
BTW, why don't you use the bump node (under vector menu) and connect it to normal socket of the BSDF?

[cekuhnen]

wow michalis

thanks for this - and yes your comment is right we dont sculpt in Blender we displace - thats the bad part.

[michalis]

@cekuhnen
thanks, we agree on this, but:
1. we don't displace in blender only, we displace on lot of other apps too.
2. Blender dyntopo is not a displacer, it's true sculpting and I love it.
3. Sculptris is a true sculpting app too.
4. Dynamesh in zbrush stands in the middle. Displace first and turn it to a true sculpting topology after.
5. We have the remesh modifier in blender which does something similar to zb, but it's limited a lot.

What I proposed here is not far from using alpha based brushes and displace on a subdivided surface. UV editor is used to control this projection. Simple.

[Sanctuary]

Nice tests Sanctuary!
You need to brake repetition of the pattern. I explained how. I guess so LOL

I actually used your UV tricks to brake the repetition on the Cube and if you look at the cube, and only the cube (not the ground) you should notice that the pattern is not repeating.
The only part that is repeated is the ground around the cube, because in fact they're just copy paste of the top of the cube , as i added that ground after doing the cube i was too lazy to redo the uv tricks

[Bernardo]

this is amazing! Thanks a lot for sharing. Still need to figure out exactly the second part of UV unwrapping, but I hope I will manage

[tungee]

Thanx Michalis,
THIS is a Fantastic Technique!
Thank you for providing this great mini Tutorial.

[michalis]

@Sdados
Follow the active quads?
You select a quad, you unwrap this only, you align it as you wish. Then, you select some quads. The previous selected quad still remains gray, blender indicates that it's the active quad. If you unwrap all these selected using "follow the active quad", they will follow this quad. It's that simple. I may didn't understand what you're asking.

[tungee]

Thanx Michalis,
THIS is a Fantastic Technique!
Thank you for providing this great mini Tutorial.
Subd=8!

[michalis]

I knew that you all are more talented than me, at least on this subject.
!!! tungee.