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mercuryrex
09-23-2004, 10:24 PM
I would like to use ZBrush 2 to model accurate likenesses of real photographs of people.

In every other 3D app, you can have a front photo of a face as a backdrop in one view, and in another window you can have the side profile of a face.

Nobody appears to be doing this, so I just wanted to find out if anybody actually is, or if it is even possible in ZBrush.

ZB2 looks to be an excellent piece of software, but I really want it to be capable of allowing me to model accurately based on a photo in the background.
I want to be able to model from photos and then map the face photo onto the head afterwards. So like in any other 3D app you can get the texture to match the geometry perfectly.

But if ZBrush only allows me to model based on guesswork as to the correct dimensions, then it's going to be a very inefficient way of modelling very accurate likenesses of real people.

How can it be done?
Is it possible to model this way in ZB2?

I have doubts because I haven't seen anybody working this way, and I can't find any tutorials about modelling with this technique.

Matariki
09-23-2004, 11:00 PM
Hi mercuryrex,
look at this thread

ReferenceImage (http://206.145.80.239/zbc/showthread.php?t=014804)

and this

QuadQuick (http://206.145.80.239/zbc/showthread.php?t=4344)

on the ZBC website.
Hope they help.
Cheers.

Kanga
09-23-2004, 11:10 PM
The most comon way is to make your mesh in another 3D application and import it into ZB for detailing. This technique also alows you to make maps for use in animation programs.

You can make stunning stills in ZB and there is a technique for doing what you are after but I have never been interested in it, so dont know.

You may not get many reactions as what you ask is about a millionth of what ZB can do.

Good Luck

aurick
09-23-2004, 11:23 PM
It's very easy:

1) Import your background image. Choose the Flat Color material, then press Texture>Crop and Fill to place it on the canvas.
2) Select a material such as Fast Shader for modeling.
3) Select the object you want to model.
4) Set the Draw>Rgb Intensity to something like 70%. This will let you see the reference image through the model while you work on it. Draw the model and start sculpting.

meats
09-24-2004, 12:06 AM
This method works, but isn't the easiest because the background is stable as you transform the object, but it can help. You just have to be carefull about not scaling your object or you will find yourself trying to match the size over and over.

Also, to map the image onto your geometry once you are done, you can use the "3d copy" feature found within the transform palette. This will transfer the image directly onto the polygons when pressed. Make sure you have a texture selected to map onto. You will need to fill the screen with a reference image with anything but the flat material, although. It won't work with the flat...

edit- just noticed that the 3d copy feature is explained very well in the reference image link that Matariki provided above...

mercuryrex
09-29-2004, 07:01 PM
Hi mercuryrex,
look at this thread

ReferenceImage (http://206.145.80.239/zbc/showthread.php?t=014804)

and this

QuadQuick (http://206.145.80.239/zbc/showthread.php?t=4344)

on the ZBC website.
Hope they help.
Cheers.
Thank you for those links, much appreciated Matariki.
I don't think Quadquick works with ZB2, it was writen for the earlier version.

The first link you provided looks like it is the best way for now.

mercuryrex
09-29-2004, 07:14 PM
It's very easy:

1) Import your background image. Choose the Flat Color material, then press Texture>Crop and Fill to place it on the canvas.
2) Select a material such as Fast Shader for modeling.
3) Select the object you want to model.
4) Set the Draw>Rgb Intensity to something like 70%. This will let you see the reference image through the model while you work on it. Draw the model and start sculpting.
Will that work properly though?

What I mean is, can you fix that as a view?
Because once you start roating your model around you instantly lose that face on view. And you can't really just try to get it back by manually rotating the model until you "sort of" get the original view here.

What I'm hoping for is some sort of precision.
Sometimes estimation doesn't cut the mustard, sometimes it's necessary to be spot on when lining things up.
If this original front view is a perspective view, straight away you are going to have problems unless there is no perspective distortion whatsoever.

I know some people on this forum will have seen some of the incredible work done by "The Ripper" in Lightwave. I know that he is looking into using ZBrush for more detail work. I'd be interested to know if he has found a good efficient way of working with ZB2 when it comes to modelling accurately from a background image.

When it comes to modelling likenesses, there may be certain features that you can't just guess on modeling and hope it ends up completely accurate.
Painting wrinkles would have to be as close as possible to the origianl background pic. You could use guesswork and get good results, but human faces are so different. So if a wrinkle or blemish is in a specific place on their face, you'd want to try as much as possible to ensure that the detail is replicated in EXACTLY the same position on your model, as opposed to just going for random generic details that just make up any old face.

Haider of Sweden
10-04-2004, 08:45 AM
Hi

About Auricks method, 1) is it possible to place that imported background image more back in Z-depth?

I mean, when I start to work with an imported model on top of it, since it dissapears partly when I rotate the modell around. Its not such a big deal, but anyway.

2) Is is possible to temporarly lock movement, rotations and scale for the polyobject? Setimes, i forget myself, and start to scale; then, I have to scale it back

Svengalii
10-04-2004, 03:59 PM
The process of using an image (or combination of front and side views on different layers) as a guide in constructing a model is made considerably easier with MOLDY2 (http://206.145.80.239/zbc/showthread.php?t=3158&highlight=moldy2) - a ZScript with axis controls and four special buttons - that let you store / re-store the model's transform position (trans,rot,scale).

As for moving the image plane back, that's easy. Look in the Layer menu and adjust the slider to a positive value (example 1000) which will move the image plane back 1000 units on Z.

It also makes sense to do the actual model work on a different layer. That way, if you have to clear the layer you don't also erase the source image.

BTW, to test the Z position of the image plane, open the Picker menu, then left-click and hold on the Z slider and drag the cursor anywhere on the canvas to see the Z value of the pixol under the cursor reflected in the slider value.

Moldy also has a Z+ and Z- button set that let you move the model toward you (Z+) and away (z-) 100 units at a time.

Sven

meats
10-04-2004, 06:02 PM
Hi Haider -

1) is it possible to place that imported background image more back in Z-depth?Yes. To do this you must use Layers. If you fill the default layer with an image, you can adjust it's placement in space using the Displace sliders. You can move any Pixols on your canvas horizontaly, vertically, or forward or backward in the Z depth.
Then create a new layer and put your 3d geometry that you are working with on that.

2) Is is possible to temporarly lock movement, rotations and scale for the polyobject? Setimes, i forget myself, and start to scale; then, I have to scale it backDon't think so. I have heard that Pixologic has seen the need for image planes and may be working on a solution....


edit - weird, Sven's post wasn't there when I wrote this...what he said:)

Haider of Sweden
10-05-2004, 10:29 AM
Meats: :thumbsup: Yeah, sometimes this forum does not refresh or something.
However, thanx for you reply anyway - it was almost the same as Svens


Sven: Thanx dude. I will also try out Moldy, since the storing/restoring position values could really be helpful.

about:
BTW, to test the Z position of the image plane, open the Picker menu, then right-click and hold on the Z slider and drag the cursor anywhere on the canvas to see the Z value of the pixol under the cursor reflected in the slider value.You meant left-click of course, right? I feel still a newbe, even though I have been working a while with Zbrush, so one small missunderstanding can make me click all day long without making it work :rolleyes:


However, since you seem to be a great scripter.
Is it possible to make some kind of Sub group script. Where you easily can see the subgroups, hide them, show them, mark or unmark them etc?

Edit/ADD: That was quite a script. Say, where can I find this storing the object's position/rotation/scale?

One more script question. Is it possible, somehow, to add an axis into zbrush? I mean, it could be useful to know where up/down/right/left is :)
Maybe some kind of a separate window, like when you drag the quadratic zoom-window in the zoom-menu while holding shift.

I dont know if I am clear enough, the script could modell/import a finished axis modell, and keep it into a layer/hidden layer, and then, have that separate window kept aside (or where ever you would like to place it) just showing the axis.

I have seen the script QuadQuick, and that has more than one window, so maybe my idea is possible to make?


Kindly

Svengalii
10-05-2004, 01:23 PM
Meats: :thumbsup: Yeah, sometimes this forum does not refresh or something.
However, thanx for you reply anyway - it was almost the same as Sven's Meats, I think the problem was that my reply was my first post on CGTalk and I guess somebody has to vet 1st time posts, thus the delay?


You meant left-click of course, right? I feel still a newbe, even though I have been working a while with Zbrush, so one small missunderstanding can make me click all day long without making it work :rolleyes: Yup, you got it. Probably explains why I can't dance, either.



Is it possible to make some kind of Sub group script. Where you easily can see the subgroups, hide them, show them, mark or unmark them etc? I would really like to build a script around subgroups using id numbers or something, but I don't think that info is available within the standard ZScript commands. Maybe someone will be able to do something like that if Pixologic decides to distribute an SDK.


Edit/ADD: That was quite a script. Say, where can I find this storing the object's position/rotation/scale? Below the axes buttons are numbered buttons (and LEDs) 1,2,3,4 and g1,g2,g3,g4. Pressing 1 will store the current transform info for the object (the LED lights up). Pressing g1 will retrieve that info and reposition the model to the stored position.

If you want to overwrite stored position, just press the 1 button again, then confirm the overwrite.


One more script question. Is it possible, somehow, to add an axis into zbrush? I mean, it could be useful to know where up/down/right/left is :)
Maybe some kind of a separate window, like when you drag the quadratic zoom-window in the zoom-menu while holding shift.

I dont know if I am clear enough, the script could model/import a finished axis model, and keep it into a layer/hidden layer, and then, have that separate window kept aside (or where ever you would like to place it) just showing the axis.

I have seen the script QuadQuick, and that has more than one window, so maybe my idea is possible to make? I guess you are asking if a script-driven tri-axis icon could be added to show the orientation of the current model? Maybe. Have to think about that. As for QuadQuick, rumor has it that there is to be a Zbrush2 version released - when? Don't know. But with the release of Z2 for the MAC, we might see new info on ZScripting real soon now. :)

Sven

Haider of Sweden
10-05-2004, 08:08 PM
Hi again Sven

About your script, thanx for the tip. It works great!

About QuadQuick for Z2; I was also wondering when it would come out. I dont know if this script is a must, since Zbrush works the way it does. Somehow you accept the workflow without needing any other viewports.

But maybe I should test it first before saying anything.

However, that tri-axis icon is still interesting. I dont know how hard such things are, but maybe you could do something likte that.
The reason why I mentioned QuadQuick is, that (what I know) it shows different views at the same time (realtime?)

So, you could let a script modell a tri-axis modell, with different colors and arrows and all those classic details.
Then, you have one small window somewhere, just like when you shift-drag the zoom-window and put it somewhere.
This small window could show the tri-axis that are located in a layer, that is hidden in the big/mail screen.


What do you think about the idea?
I am sure an axis is useful. My only way to know where I am right now is either that I know how the modell was modelled in Maya, after that I imported it into Zbrush, or that I turn on X/Y or Z symmetry to find out where I am right now :rolleyes:


At leas I will be happy for this script :bounce:

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