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bongob
09-08-2004, 11:58 AM
Ohho Hello there!

I plan to buy Zbrush...
I read around, downloaded the Demo, played around and really like Zbrush!

But I am very new to CG and I need a proper workflow in order
get some good results - until now its all about learning - the
output is very low quality (demo limitation) .

I read that the general workflow would be like:

Export your Low Poly Model (LPM) into Zbrush (out of ya main App or modeler) get some awsome detail - unwrap and
wrap on ya LPM....

But there is no main App i can use yet - nor a Modeler.
So i am not able to produce LPM yet!

So my concern is:
Shall i go for: Silo, 3dWings, Xsi or Maya -
in order to make LPM 1st and then create UV's with Zbrush.

Or can i take the way reverse??

I read this interesting interview yesterday - a Doom Modeler using Lightwave.....

"How do you go from the high poly mesh to the low poly one?
When I make a low poly version of the high poly model, I take the high poly model and put it in the background and make the low poly polygons one by one over it. I never work with a model that's one contiguous solid mesh, so I can never run an LOD on the high poly mesh to create the low poly version. I really wish someone out there would create a tool that would merge all of the floating meshes into one contiguous mesh so an LOD would be possible. Especially considering how normal maps are becoming the industry standard. ZBrush actually can do that, but the polygonal accuracy isn't high enough to be able to use it properly. :(

I actually did use the ZBrush unified mesh tool once on a pretty simple model where its accuracy would work out, and it took me longer to clean up all the holes in my model than it normally takes me to make my low poly mesh poly by poly. The reason why there were holes, was because my high poly model was flawed. There were a couple of floating meshes that had little gaps between them."

What is that "LOD" and WHY is he going from the High Poly Model
down to the Low one - hes working reverse.....

I am just confused...pls clean it up for me!

Joe_Coolish
09-08-2004, 05:00 PM
You can model in ZBrush. The ZSpheres are great for modeling. It sounds like your making game models, and zb makes great low poly models. The ZSpheres in ZB2 make some of the best polies compared to other blobby modeler. if you look at the poly line from zbrush and then from a program like Clay Studio for 3ds max, you see just how powerful Zbrush is. If you want to spend the money to get an other program, I'd suggest 3ds max for games, but if it's film, go for Maya. Try them both out. Those are the to ends of the 3d app spectrum. XSI and lightwave are great too, but I haven't really ever used them. But that's IMO. Try before you buy, which ever one isn't akward, go for it. Good luckJoel

Goon
09-08-2004, 07:31 PM
Silo and wings3d are very good, and will serve you well. However, be aware that you will still need Max, LW, Maya, XSI, C4d, Blender, Houdini, or some other app to render out displacements. XSI foundations is an excellent place to start: $500

Also, know that the Auto UV tiles that Zbrush generates, while good for its purposes have the disadvantage that it is impossible for you to paint textures in a 2d program.

So possible workflows:
low poly model: generated in wings3d, silo, zbrush, or a Major App
UVs: wings3d autoUV tools (excellent), zbrush, or a Major App
Render: zbrush, free renderman compliant renderer, or a Major App

Some peope generate a high poly rough in zbrush, and use this as a template to create the low poly shape, via Maya's live surface tool, Silo's paint topology tool, or another equivalent. They then go in and detail the model in zbrush again.

Nemoid
09-08-2004, 08:13 PM
if u're going for animation, IMO a good way to work is to model your low poly mesh directly in an app like Max , Maya, Lw or other then import it in z brush and start the funny clay like detailing! then extract your normal map and apply it to the low poly mesh, so u'll get all the detail u sculpted in rendering.
u could work in ZBrush with z spheres as well, but while u get really good shapes in general, the polyflow isn't easy to fix for good deformations. when some tool will come to do this in ZBrush it will be a great day! :)

P.S. u could also start your low poly model with z spheres and fix its polyflow into another app. this could be also clever. building natural shapes takes minutes in z brush , while in other apps can require alot of time.

KidderD
09-08-2004, 09:02 PM
if u're going for animation, IMO a good way to work is to model your low poly mesh directly in an app like Max , Maya, Lw or other then import it in z brush and start the funny clay like detailing! then extract your normal map and apply it to the low poly mesh, so u'll get all the detail u sculpted in rendering.
u could work in ZBrush with z spheres as well, but while u get really good shapes in general, the polyflow isn't easy to fix for good deformations. when some tool will come to do this in ZBrush it will be a great day! :)

P.S. u could also start your low poly model with z spheres and fix its polyflow into another app. this could be also clever. building natural shapes takes minutes in z brush , while in other apps can require alot of time.
I just had a question about the above workflow.

How can you create other maps, color, spec , bump, if you use this workflow. I don't think that you can use the zbrush uvs for this, can you? Can you use separate uvs for different mapping, not that this would help of anythiing, I think that the uvs need to laid out first. And then, proceed with the above workflow. But, I was wondering if anyone was somehow having success with zbrush uvs for anything other than displacements, I suppose one could make color, etc maps in zbrush, is anyone using that as their workflow?

freka01
09-08-2004, 09:37 PM
For making texturemaps you would use the projectionmaster together with 3dCopy. There is a great zScript tutorial for it. Makes great seamless and crisp textures for native as well as imported geometry.

Joe_Coolish
09-08-2004, 09:37 PM
that's the original purpose that I got ZBrush, was to paint the UVs. It's a lot easier than say . . .DeepPaint. The 3d modeling features were just a perk. Watch some of the tutorial scripts. There is one that the artist makes a Buda type head and then paints it this metallic color with the hint that the surface underneath was skin. Painting on 3d models is almost too easy in ZB. If that's what you want, you won't be disappointed.

gl

Joel

Goon
09-08-2004, 10:08 PM
Joe_Coolish: how do you handle painting multiple channels, ie diffuse, specular, etc.

Joe_Coolish
09-08-2004, 10:40 PM
Things are easy to find if you look.

1st step (http://www.cgtalk.com/showthread.php?p=1561793#post1561793)

2nd step (http://www.pixolator.com/zbc-bin/ultimatebb.cgi?ubb=get_topic&f=1&t=014968)

3rd stop (http://206.145.80.239/zbc/forumdisplay.php?f=41)Just like that :thumbsup:

Cheers

bongob
09-09-2004, 12:41 PM
Joe_Coolish,

yeah games would be fine, though my purpose is to create useful
models (LPM) whether they are for games or little animations.

But i can't imagine using Models created from zspheres!?!
I definitely enjoy Zspheres! But they need to be cleaned
in order to produce some more "high tech organic's" for example!
(like anatomy->hands)

Well - the application question will be a forced decision - just cheap.


Goon,

yeah - you strengthen my thoughts on Silo/3DW and XSi due to that price...However is Zbrush working seamless together with XSi?
You seem to stick to 3dWings - however I will stick to Zbrush :>

"Some peope generate a high poly rough in zbrush, and use this as a template to create the low poly shape, via Maya's live surface tool, Silo's paint topology tool, or another equivalent. They then go in and detail the model in zbrush again."

That's exactly what i wanted this threat to become to! Go the way reverse - This "Doom-Guy" used this method (the quote above)
and here is the whole interview - its very funny/informative read!
though I don't understand everything....

http://www.newtekeurope.com/uk/community/lightwave/menard/1.html

He is commenting on ZBrush's accuracy -

"Especially considering how normal maps are becoming the industry standard. ZBrush actually can do that, but the polygonal accuracy isn't high enough to be able to use it properly. :("


Nemoid,

this workflow is the usually way, i would like to know more about the reverse way - So i could actually start with my HighPModel in Zbrush and later define the suitable Low Poly Model in what ever APP....

"The polyflow isn't easy to fix for good deformations"
->that was my point above - pixo will fix this probably soon

:>

Ok my questions:

"1) Scribble out an idea very quickly if I must;
2) Model the high poly version;
3) Model the low poly version;
4) UV the low poly version;
5) Create a shader and render the high poly normal maps for the low poly version;
6) Paint the diffuse, bump, and specular maps for the model."

-Is this possible with Zbrush - any ZScript?
-Or am I limited to just one Displacement map??
-What are diffuse, bump and specular maps???
-What about Half-Life - are there any parallels...

...ok lunch break...

Nemoid
09-09-2004, 06:07 PM
uhmm.. ok you would like to model the high poly mesh in z brush with z sphere's and then import the model into another app like maya and work with this like if its a 3d scanned maquette. of course this is possible. there's also a really interesting thread about this with a Zbrush/XSI process in zbrush central. if i have time i'll search for it for u.

if you watch some of the movies around about z brush u end up to know that with z spheres you can model what u want actually. the problem relies more in deformations and facial animation.
that's why usually a good process for animation is to build the low poly mesh traditionally in your major app and create fine details later. this seems to me a more clever approach,also because you become used to accurately place good geometry into your mesh for usual details. then add some very fine skin and surface details u can obtain only with z brush into an easy way.

Joe_Coolish
09-09-2004, 06:38 PM
About the hand thing, one of the most realistic 3d hands I ever seen was made and rendered in ZBrush.

http://209.132.69.82/zbrush/zbrush2/images/Gallery/rimasson3.jpg

ZBrush is all about the organic. It's like building things out of clay. With ZSpheres, you can start with a concept, ruff it out with the ZSs and then fine tune it with the painting tools. You need to try ZB2 and not ZB1.55 or what ever the demo is. ver 2 vastly improves the modeling. My personal favorite is the new masking

http://209.132.69.82/zbrush/zbrush2/images/Gallery/Menta-Ogre.jpg

Yeah, ZSs can model organics pretty easily

bongob
09-10-2004, 01:19 PM
Nemoid,

Exactly, I want to do this cause i am not capable of any major App
nor am I into any Modeler. So i would be able to create obj. within
Zbrush2 without bothering about polys, vertices and all that stuff.
Later i could use them within my future App...

So this threat isn't about whether Zbrush's Zspheres are good...
It's about helping a newbie to work out his "workflow". My approach
is to use Zbrush combined with my drawing skills to get the maximum out of it...until now I am stuck - due to the Demo and
thats why I am considering to buy Zbrush...
(for me -> five month "income")

Moreover, I will probably get a placement... it's a little studio.
When i was phoning him, he told me that i need to have some
experience within XSi...I have got the EXP version but i never gave it a try, yet - I just told him that i am using Zbrush...

And that's why i am asking these questions...

Is Zbrush limited to one Displacement map??
What are diffuse, bump and specular maps???
Can i paint with PhotoShop on the Displacement Map?
Will there be some "less primitive Primitives" - especially
for human anatomy...?
What is that "LOD" and WHY is he going from the High Poly Model
down to the Low one - hes working reverse...BUT NOT because he
is a newbie like me....

Coolish,

About the hand thing...I can model Hands with zbrush
(2mounths of 3d) But i can't Sketch them with Zsphere's...
I definitley need some other App in order to work out the
rough shape...

bongob
09-10-2004, 05:12 PM
i will focus on human anatomyhttp://www.zbrush.de/images/uploaded3/user_img-fmgdAOooD1_Can.jpg

celmar
09-10-2004, 09:58 PM
of course, you can do a whole picture in zbrush... mainly in what is called "organic" forms; it's living forms... happily, living forms are the most interesting form of life on our world (with the exception of a cup^of coffee, when really tired)... for other forms, like industrials ones, you have to use a classic software, in nurbs (rhino) or in poly (others)... but you can import all that stuff in zbrush , and modify it... the only questionb is: what soret of picture do you want to create... in other words, the answer is "inside" your artiostic needs... once you answer to that, you answer to trhe technical questions,...

Nemoid
09-11-2004, 02:22 PM
Maybe i miss the point, but your real prob is if u want to work for animation or not.

however u can start like this :
1) draw your z spheres char . by this u end up with a low poly mesh u have to re work a bit
2) with your LPM at 1 subdivision, start to ad some other edgeloop where u need it .

unfortunately, z brush doesn't have great tools to edit and rework the polyflow orf your LPM, so, what u can do is getting your shape better fitting your char. u can do this with LPM subd 1 or 2

3 make your adaptive mesh and then divide it, so u get a smoother and divided one with many polys . the more the polys the more smoother it is and maybe the easier u sculpt.

4) update and sculpt your final detailed mesh , everytime dividing it. u can go at a lower level of detail any time u want

this is for sculpting, but then u'll have to export a lesser defined version of your model and create a LPM into another app, just because u'll have to fix the polyflow. u can do this in apps like Silo wich is affordable and have a paint polyflow brush.or go into any major apps with similar tool like Maya or XSI.u will use tools wich are good forworking scanned digital maquettes, but you'll have your shape guiding your (long) work. this is helpful for animation because if u have not a good polyflow, the mesh will animate badly.

then, now you have 2 mesh : a LPM done in lets say XSI and a hiperdetailed mesh in ZBrush. u will have to use an external plug to extract a displacement and/or normal map, to apply to your LPM to obtain all the high poly mesh detail at render time.

if u want, u can do this in Zbrush instead, extracting the normal map directly from your model, then going to a LPM level, and applying it (some of this process is showed in Ambient Whisper's doodle movie)

as u can see the process depends from your needs.

P.S. the reversed workflow working in ZBrush at the start can be done, but it's a long process. the normal , more linear way would be to build your LPM in a major app, but it isn't your case.in your case you'll have to use an external app however, if u want to fix topology.if you're not going for animation, then u can do all in ZBrush.

however in this process, since you have good polyflow before going in ZBrush , and u can also rig and UV the mesh before importing, things become easier in z brush where you go and model the finer details that bring your model to a further level.then simply extract the normal map and apply to your LPM.

cheers . hope this has been useful in some way. :)

bongob
09-11-2004, 04:12 PM
THX a lot nemoid!

bongob
09-13-2004, 02:45 AM
Zkull ->


http://www.zbrush.de/images/uploaded3/user_img-z5ojMWmbB3_Zkull.jpg

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