Thanks again
1.In Blender is where I found to be easiest way
2.Radnom it is… I need controlled… However I found different ways to cheat
3.Still cannot apply ANY modifier to selected part in Blender… It affects the whole mesh always (simple texturing works OK to do with multiple UVs, but not the modifiers). Any idea?
Cheerz
In some modifiers, such as the displace modifier. you can select a vertex group so the modifier only affects those vertices
You do pull off new and interesting uses for this. Here you have created something that looks like a cross between architecture and engineering. Such clever use of all you have shown us here.
I would really like to see the mesh without the displace modifier turned on. Can you do an edge render or screen grab? I find it useful and inspiring to see the work, before and after the UV displacement sculpting.
Also, thank you kindly for updating the original posts with links to the various tips and tutorials along the way. I have bookmarked so many pages but not noted which has what information, and with such a long thread it’s hard to find what you are looking for. I am going to try collecting it all together for my own reference using Springpad or something.
@Michalis, great one, I could see that being used for an anime or a futuristic episode of ray and clovis 
Congrats, michalis, you’re yet improving this technique. I’d like to see the raw mesh too.
Thank you.
Too kind of you.
@Anthonis,
Have a great time in Amsterdam.
Yeah, Psy-fi is there alright.
Have you used vertex groups before?
Lets use a basic cube example. I’ll subdivide it a couple of times and apply.
In edit mode, ‘face select’ the front and top faces.
Go to the Object Data tab, the upside down triangle, under Vertex Groups press the + button to create a group, give it a name like v#1, then hit Assign.
Ctrl I to invert the selection, then create a second vertex group named v#2.
Actually I tested it and found that we don’t want to assign the vertices shared by both groups of faces so go into “edge select” mode and deselect everything except for the edges at the border of the selected area. Circle select works well for that (C). Then hit the Remove button for both vertex groups (select a group, hit remove, select other group, hit remove).
The vertex groups are taken care of, now go to modifiers and add Subdivision Surface and Displace, as normal for this technique, but select v#1 for the vertex group. Do a single unrwap and arrange your faces with your displacement map as desired.
Then create another Displace modifier and select the v#2 vertex group, load up another displacement image, move the relevant faces into position but you don’t need to unwrap again (you can select the specific faces again using the vertex groups section in Object Data, BUT because I told you to unassign that line you should ‘grow’ your selection to cover the border faces).
Now you have displaced your vertex groups individually using different displacement maps.
I suspect that you also are unaware of the UV Maps section in the Object Data tab.
Edit: I read your post again and you do mention having the UVMap names correct, so you do know this. See below anyway.
In there you can create a new UV Map by clicking the + symbol. Make changes to just that UV Map. You can click on the two maps and jump between them in the UV map viewport to see how they compare.
In the Displace modifier there is the UV Map section under texture coordinates, so you can select the new UV Map in one of your displace modifiers (make sure each modifier is using a different UV Map). You should do this in conjunction with the Vertex Groups, so that the faces you do not want to be effected are controlled by the other modifier.
Give it a try. I just did it as a test and will post the render.
Just a quick and dirty test. Top and left use a different UV Map and Vertex group than the rest.
The basic shape does need more subdivisions and I did nothing fancy at all.
I would point out that because I removed the border vertices from both vertex groups there is an obvious crease where the groups are blending in to each other. It may be better to weight paint to border area to get a more subtle effect. It would smooth it out more.
Also see earlier posts and tutorial about using weight painting vertex groups to get some amazing effects.
Speaking of that, michalis do you have any experience or does anybody have the time to test a few things:
At the moment I am creating simple elements and throw them at a particle emitter. (Or several if I want more control of the “layers”).
I admit that I do that because I’m just too lazy to actually model a complete displace/bump map and it creates interesting things fast.
Then I render it as emission and AO to a 2048x2048 image with about 1024 samples.
(I’m pretty sure michalis linked to everything I said in his second post.)
After a while I stumbled over a few things. Not sure if they were discussed already.
In the render tab, under “film” there is a Pixel Filter, set per default to gaussian and 1.5.
If it is anything above 0, it causes some type of banding, that is calculating pixels between the “high” white object and the “low/base” black background.
I think filtering is necessary to get smooth gradients but might mess with the displacement settings (Details as to why in the next part).
Has anybody fiddled around with the setting to see what happens later?
Displacement and the scale of objects on the texture.
Normally I like to cram the bump/displace texture full with small objects, to have more variety.
As bump maps, this works fine.
But the displacement modifier doesn’t like that very much. Having too many “objects” within one UV quad the displacer can’t fit the subsurfaced quads to them very well and when you scale the uv down on a detailed texture, the displacer has a hard time with the above mentioned banding pixels.
So I think it would be a good idea to find out if there is an optimal scale of objects on the displacement texture.
Also I think I get one of marc’s points now. If I’ve got some time I’ll set up a few maps to see how an object should be build on the displacement generator to give the most smooth results. This could solve the above mentioned problems to a degree, too…
Sorry, not at home PC, so no pics to show what I meant. 
I myself would use big textures just to paint more different designs to displace with
That’s what I’m trying to find out: What is a good resolution for displacement?
Or: How many pixels do you need to get a good, clean displace?
Just some basic stuff to keep in mind when creating the displacement texture.
From there you can work your way up until you’re out of RAM. (And/or switch to bump design only to find out that it’s much more forgiving and you didn’t need those 500MB textures.
Sir, your replies are accurate.
Regarding resolution: a 2048x2048 is enough assuming it is a tiled map.
Keep in mind that it should not be confused with the subsurf resolution. Because you will also use it as a bump map. You might also mix (cycles or BI) a second bump (displ 32bit map) using a different UV set for high freq details.
About the banding effect (gaussian 1.5) I never noticed such artifacts.
Supposing you assigned the right distances under emitter setup. A possible test: a hemisphere. Burn the map as 32 bit. The displ modifier should reproduce a hemisphere if midlevel=0
I also tested depth maps, baked in zbrush. 16 bit tiffs. Still no banding.
For best results you better add render bump support on the renderer. In this case, AO map should also be used.
New work LOL
just now I cannot spend time to learn it in details), so I will export hires meshes for posterior use. Never material-displacement in Blender.
You probably mean Lores meshes, right? You can use the GLSL viewport renderer, and have nice bump previews as you UV “sculpt” your mesh. I do it all the time if I export to zbrush for instance. Same goes to zbrush. It has a very nice and sophisticated displacement preview (mode). It doesn’t displace the base and you can export the maps + UV unwrapping elsewhere.
By the way, is there in Blender a way to select faces by applying color information on them? (volume select by texture in MAX)
I think it is already answered in the support topics of BA. You can assign colors to selected faces and select by color then.
I’ll post pics of my “issues” when I’ve got some time at the weekend. And a few new bumpmap landscape tests to make up for the wall of text. 
btw did you render the particle emitter or are you going to claim that you found a way to fake shadows with bump/ao maps?
You mean then, not export, render, yes?
I’m a little confused. Sorry.
@sir, right, these are layers of emitters. Instances (by particles-hair)
Why to go this way mort agon?
If displacement gonna take place in blender, it can also happen under zbrush or max or any other app?
Think about it, let’s be practical. The only you need is to export the base and the displ map. All information is there.
In fact, this is why I started this thread.
To be able to export only what you need.
Else, I could stay in zbrush and do all the magic there.
endless Z possibilities, resulting to a 8M or a 16M faces unsubdivided mesh-obj.
Indeed zbrush is still a 32 bit app.
However, what a surprise.
Go for a 16M subdivisions (the limit) and everything works just fine.
It isn’t related to GPU as well. Magic! Nothing to compare with the viewport of blender
A bit out of topic. Sorry.
wrong post, sorry
I said convert normal to displacement, because I read today that Crazybump is doing it VEEERY well, and because I succeed to export normal map from MAX, and not succeed to export displacement map.
Well, Crazybump is a very handy application, I have tested it a lot.
However, it will convert normals to displacement maps veeeery wrong. Because normal maps don’t have a height information at all.
Here a test: Some cubes on a plane. Normal maps from side and top views. There is no depth information, the top view equals to a single flat plane. If a little bevel and smooth shadowing added, you may also have some curvature on edges. Again, all the cubes will have no height information. This is all about normal maps.
Nothing will happen in crazybumps if you try such maps.
Please, this is not a general discussion thread.
It is a blender tests topic.
There you could post, ask help or discuss such things
here:
http://blenderartists.org/forum/forumdisplay.php?24-Other-Software
Sorry too mort agon, trying for a little moderation, this thread became chaotic.
However, you see my point on the above example about normal maps. No height information. This could be the reason why you’re trying to blur height maps before converting to normals. All these are just workarounds, tricks.
