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Pavlov
06-08-2012, 08:20 AM
hi all,
a client gave me mesh in pic 1, which is scanned in 3d. no editing is possible.
He wants same kind of wrinkles in a smaller and different cushion, the one in pic2.
Now, i'd like to tranfer wrinkles in the smartest way.
I think i need kinda a Z-buffer of scanned mesh, something which tells how distant each point is from same shape but clean, with no wrinkle.
So i thought about modeling a clean envelope for this object and use it as advanced camera, and bake Zbuffer and normal maps.
Difficult point is how to project these two on clean shape in pic.2 Would you build manually an UVmap, or is there a smarter way to get UVs corresponding to advanced camera shape ?
A beer to all those who will even understand my question :(

Paolo

Pavlov
06-08-2012, 10:21 AM
PS - i may need someone to model for us some pieces like this from now to end of june. BTW it's a paid work but result must be excellent - no normal maps or bumps, i need someone to model it or sculpt it in Zbrush with real geometry.

contact me privately, please.

thanks,
Paolo

Danner
06-08-2012, 12:13 PM
http://www.trueart.pl/?URIType=Directory&URI=Products/Plug-Ins/Push

I haven't used it but sounds like it would do what you need.

JoePoe
06-08-2012, 12:42 PM
here is a very quick example.... not of a pillow, but easily applied to pillow shape of course.
All geometry... high poly count, but all geometry.

(added the last one to get a bit closer to your image.... again quick example).

http://i1049.photobucket.com/albums/s395/joepoe1/clothfront.jpg

http://i1049.photobucket.com/albums/s395/joepoe1/cloth.jpg

http://i1049.photobucket.com/albums/s395/joepoe1/cloth3.jpg

jeric_synergy
06-08-2012, 12:50 PM
here is a very quick example.... not of a pillow, but easily applied to pillow shape of course.
All geometry... high poly count, but all geometry.
Nice. Technique?? Or proprietary?

JoePoe
06-09-2012, 11:46 AM
:) I used a greyscale image of fabric wrinkles to displace geometry in obj properties.
Pretty simple, just gotta be willing to crank render subpatch level way up.

In Pavlov's case... in order to replicate to same folds from the big pillow, I'd do a nice big render of it with the ortho camera (careful to light it in such a way as to get nice shadows of the folds but trying to keep the main pillow surface as "flat" as possible.) tweak values as needed in Pshop and also resize to get the new proportions and use that image to drive displacement on the smaller pillow.

I used the same technique to get the treads on my flip-flop model from one of the speed model challenges. (used a procedural,not an image, on these, along with a weight map to control influence...:hey:).

http://i1049.photobucket.com/albums/s395/joepoe1/FF2b.jpg

jeric_synergy
06-09-2012, 12:21 PM
:) I used a greyscale image of fabric wrinkles to displace geometry in obj properties.
Pretty simple, just gotta be willing to crank render subpatch level way up.
Thanks Joe.

So, this is just straight displacement? No normal mapping (a procedure I've yet to wrap my head around*)? Surprisingly good results.

(*The various explanations I've seen always seem to have a LOT of steps.)

JoePoe
06-09-2012, 12:51 PM
yup, straight up geometry displacement . But it requires a massive # of polys. Kind of like a Zbrush model before a normal map is exported. (pavlov said no normal mapping. Trust me, I would have preferred it).

I've recently started to get my head around normal maps myself. I'm no expert, but if I may.....

Do you not get what they are?.... or, how to make one?

One of my first normal maps was the wave pattern on the flip flop strap above....

jeric_synergy
06-09-2012, 01:28 PM
Do you not get what they are?.... or, how to make one?
Rats, I was hoping those were links. :)

I pretty much know what they are ("super displacement maps"), I imagine, but the explanations of how to achieve them seem, to this lazy lazy bastard, to have many many steps.

Anyway, no worries, they're on my list of "things to comprehend someday". By that time the procedures will probably have changed. :D

JoePoe
06-09-2012, 01:43 PM
Jeric I bet I could give you a run in the lazy category.

If you can click one mouse button you can make normal map.
I use nDo plugin for Photoshop. Its an action script. All you have
To do is hit run. I'm on a very very old Mac (pre intel) and my options were limited. There is also an Nvidia Pshop plugin and some good stand alone programs. I'm typing on my phone at the moment. Will post some links in a bit.

jeric_synergy
06-09-2012, 02:02 PM
Jeric I bet I could give you a run in the lazy category.
I'd argue the point, but that's too much work. :D

JoePoe
06-09-2012, 03:14 PM
I'd argue the point, but that's too much work. :D :lol:


...they are ("super displacement maps"), I imagine...

Hmmm, well that may in fact be what they are called, but I prefer to look at them simply as bump maps on steroids. They don't actually (as far as I understand) displace anything, they just give the illusion of displacement.

Anyway.....

nDo2 (http://www.quixel.se/) I'm not sure where nDo(1) went. That's what I use.
CrazyBump (http://www.crazybump.com/)
nVIDIA Pshop plug (http://developer.nvidia.com/nvidia-texture-tools-adobe-photoshop) (if you have an nVIDIA card I believe)
...I'm sure there are others!

BTW, these are not the same as sculpting a crazy detailed model and extracting a normal map, but pretty useful in their own right.
:beerchug:

jeric_synergy
06-09-2012, 05:03 PM
They don't actually (as far as I understand) displace anything, they just give the illusion of displacement.
See, I already learned something.

So, like a bump mapped sphere, the profile of a normal mapped sphere is still going to be perfectly spherical? (Or circular, to be pedantic.)

JoePoe
06-09-2012, 05:14 PM
See, I already learned something.

So, like a bump mapped sphere, the profile of a normal mapped sphere is still going to be perfectly spherical? (Or circular, to be pedantic.)

EXACTLY correct :thumbsup:! That's where the illusion breaks down. The silhouette of a bump/normal mapped object will not show the effect.

The flip flop is a good example of this. The tread seen straight on, or even at an angle from a distance, could be done effectively with a normal map. But, once you get up close and look from the side, that saw tooth pattern really needs to be actual geometry.

jeric_synergy
06-09-2012, 05:16 PM
So, in node-speak, each rendered 'spot' is getting its normal changed by the normal map process. Cool.

When generated from geometry, what happens in an overhang/recurve situation?

JoePoe
06-09-2012, 08:03 PM
Well, I don't know about the "node-speak", but...


When generated from geometry, what happens in an overhang/recurve situation?
Ah ha! Now you're getting into the meat.

Full disclosure... I have zero experience with ZBrush.
But, that's the rub. From what I've heard/read it's very important in ZBrush to start off with a very clean mesh in order to maintain clean normal info throughout it's massive poly interpolation process.

Try it and see what happens. Sculptris (http://www.pixologic.com/sculptris/) (and that is a link) is ZBrush's little brother and FREE.

Also, there is a process to obtain normal info directly from geometry in Lightwave itself. I believe it came from XswampyX. (I'll try to find it).

JoePoe
06-09-2012, 08:17 PM
normal map from geometry in Lightwave...

read these two threads....(only two & three pages respectively)

http://forums.newtek.com/showthread.php?t=127732&highlight=speed+challenge

and this second thread is referenced in the first one.

http://forums.newtek.com/showthread.php?t=115614

Danner
06-09-2012, 09:52 PM
An over simplified explanation of normal maps:
They modify the normals of a surface (even one polygon can have a complex normal definition) based on an image, the different colors define what directions the normals should be facing. This makes sense if you know what normals are..

They do not displace geometry, in that sense they are like a bump map. The diference is that bump maps use gray scale data to define low and high points, and normals define direction, not height.

I' post some exaples tomorrow using the awesome Bump to Normal node by Dpont.

geo_n
06-10-2012, 12:52 AM
This is where 3dcoat always saves me.
Either go the retopo route or displacement and normal maps.

Pavlov
06-10-2012, 04:21 AM
i already tried baking normal maps from first one and tranferring them to second one. I also baked AO pass to use it as displacement. anyway result is fakey. I need something extremely realistinc, not something that may look ok. So i guess i'll give a try tomarvelous designer or i'll try ZBroad.

JoePoe
06-10-2012, 10:55 AM
...even one polygon can have a complex normal definition...

Yes, of course, that's the "on steroids" part. :)

Looking forward to your Dpont Bump to normal examples.
Just tried it, and I get the same result as using just bump.
(please see attached)

Maybe I'm using it wrong?? :help:
(and yes, I did go to the Dpont site and recreated the node tree that the bump to normal node replicates..... same result.) :stumped:

Pavlov
06-10-2012, 01:47 PM
geo-n, i really must dig one of these damn tools one day... i'm not sure about 3dcoat or Zbrush. I tried 4d coat but making something like this from scratch, just with brushes... seems quite impossible. Maybe with a tablet.. who knows.

paolo

JoePoe
06-10-2012, 01:53 PM
Hey Pavlov, is there a chance you could post the big pillow object?
(Or is that a restriction from the client.)

I'd like to fool around with this.

Pavlov
06-10-2012, 02:15 PM
eh... sadly i cant ;(
nda here.

Paolo

erikals
06-10-2012, 09:00 PM
 
i'd "extract" "make" the displacement map first >
http://www.youtube.com/watch?v=O7fINI4DpeI

then map it onto the new UV mapped object >
http://www.youtube.com/user/erikalst/videos?query=plg

 

Pavlov
06-11-2012, 01:59 AM
Erikals, thanks... interesting, i just wondered how to extract wrinkles using a proxy object.

Paolo

probiner
06-11-2012, 07:01 AM
Hi Pavlov.
Tricky indeed.

Options from the top of my head:

1 - cut sections of areas of detail, from the high detail triangulated mesh.
The use a low polymesh to control them (MetaLink) and warp them around the new Object. Then blend the new object with the sections
MeshMixer (http://www.meshmixer.com/) might provide tool for the same midset of making cuts of detail and apply them to a lower res object.

2 - Get the topology of the new model to shrinkwarp to the dense mesh, but like there were no wrinkles, as if it were a low res retopo with no detail. Bake high to low.
Now, before the bake, you space the mesh and/or space the UV so that when you morph back the topology (to the state you have in the first image) the wrinkles don't very distorted.
Even though you'll be capturing the detail, it might require some recurssive work to get the detail undistorted, but them being pillows, might not be that hard and maybe you, again, just need sections.

3 - Get both objects into an adaptive sculting app and shaphe the high detail into the low, triming the sections you don't need and if sculpting perse is not good to pose the high, maybe a lattice deformer will do the final touch.

4 - Do these other threads of yours gives you any ideas?
http://forums.newtek.com/showthread.php?t=122505
http://forums.newtek.com/showthread.php?t=121154


Good Luck
Report solutions :)