Multiple objects / one map / Blender

Hello,

Is it possible to bake one map from multiple objects in Blender ? Will it leads to more acurate sculpties ?

Thank you...

I don't know a lot about blender, so can only go from what I know of other programs which use poly based modeling.

Short answer - no.

Long answer - no, not unless you know how to reduce the meshes of the various objects so the total number of verts is 1056 and it unwraps to create a square mesh once they're all combined into one.

Although you could probably do it with nurbs as it acts more like a wrapper and the mesh has little or nothing to do with the finished object. You won't get any more detail though, you'll always be locked at 1024 faces.

I started to answer your question by guessing what you might exactly want to achieve, but then i realised, that it is better to ask, what you exactly want to do and maybe why you want to do that ? I don't get why i would want to create one map out of many objects. I can understand the opposite though (create many sculpties from one object to get higher precisison...)

So the best would be to describe your particular problem/idea in more detail.
Anyways, below you see some (bad) hint about how you could do something, which i never ever would recommend to do. But as i don't know what you are aiming for, maybe your use case is perfect and i just haven't thought about it...


==== So here is one possible approach (WARNING: BAD COMPLEX BAD COMPLEX ...)

Do you want to generate one sculpt map from one or more arbitrary objects ?

As Bonk Said you most probably will suffer from the limited amount of mesh points and from the very limitted spatial resolution of sculpties. (You have only 256 possible locations along each axis of your object to place the mesh points, which often makes people going crazy)

But ok, you could do it if you take care, but i don't think it is feasible:

- in object mode SHIFT-right click all objects you want to take together.
- Then join objects (somewhere from the mesh menu option), which effectively makes one combined object out of all.(good news: You can separate them again later)
- UV-unwrap that object... ok, ok... this will be the hardest task. I do not at all recommend to do this, except you are very familiar with UV-unwrapping. And i even am not sure, how UV-unwrapping would deal with non-connected submeshes which you will definitely have in your combined object...

But the more i think about it the less convinced i am that this should be done. At least i realize, that i would get many problems when i wanted to try that...

======= There is another option, which may... give some reasonable results: Use the shrink wrap modifier... I assume, you have Domino's scripts at hand, then this approach would be easy to check out:

- Join the entire collection to one object (as expleind above)
- create a sculptie of the type which fits best to your particular setup. I think that "sphere" is a good guess...

- scale the sculptie up so that your whole collection is laying INSIDE the sculptie.
- Then add the schrink wrap modifier to the sculptie.
- shrink wrap
- make final adjustments.

Again a warning: If your object collection is complex, you most probably will fail with this approach. If you object collection is simple in topology, you probably get better result when working out your sculpts from scratch, maybe taking your object collection as "a model" around whihc you sculpt your sculpties... and maybe that is the best idea of all i mention in this post

have fun and good luck
Gaia

Thank you for your answer. In fact, it's for a friend who want to do hemstitched objects, like chairs with hemstitched back and she has been said that the only way to achieve that was to make several objects in Blender and to gather them at the end in a single map

I still do not really understand what you/your friend wants to achieve. Maybe a foto could help ? or a .blend file with a model made out of several objects, for which you want to make a sculptie ? put it somewhere on the web and tell us the link, or if that is not feasible, you might want to send something to my email account at

[email]gaia.clary@machinimatrix.org[/email]

cheers

It's possible to make this with one sculpty, but not in the way you're inferring.

I meanwhile found the meaning of "hemstitching"... Can it be, that you want to achieve very subtle effects ? You want the stitching itself to be sculpted ? Can it be possible, that the effects you want to achieve are also doable with bumpmapping/shadowing ?

If that is so, you could create a high resolution model, texturize and add shadows to it and then bake the sculptie texture out of it. That is certainly doable in blender. On the sculptie it would "fake" 3D effects but that would be absolutely ok under almost any circumstance. Maybe not when you make giant pillows or such .

In fact as i understood it, Bumpmapping is such a technique to make low poly objects look as if they had a much higher detailed mesh. So that could be usefull in your case...

Again: a picture would help, otherwise we are surfing in the dark

She wants to get result like that :







on other objects and had been told that to get only one prim for the upper or the lower part, she had to make several objects in Blender, join them and bake them in a single map.

From all i know about sculpted prims i can tell you, she has been told wrong.

The chairs you show in your pics are of a topology, which is not supported by Sculpted prims. In short words, sculpted prims support one hole in the mesh at maximum, while your chairs need much more (i count 10 holes on the upper part alone).

ok, you could get something done, when you use the techniques to "make separate object out of one sculpted prim" and rearrange these "separated parts" in such a way, that the desired effect can be achieved. But from what i see on your pics, i think it is not worthwhile the try. You will most probably suffer from LOD effects and from resolution/precision effects, so your chairs would not look at all as expected from a slight distance. But maybe you could get something out of oblong sculpties ...

So... i'd say, forget it. But i guess there are much better builders around here, so don't count too much on my word. I have very often been wrong So if there is a reasonable solution to make such a chair with only one sculpted prim, i very eagerly would like to study that solution!!!

If i had the task to do something here, i would go with a mix of standard prims and sculpties, but i would need about 7-8 objects for the upper part and 8 Objects for the lower part... If i needed to take care of "prim efficiency", i would consier using alpha textures on standardprims for some parts so i could reduce the total count of prims...

But at no moment i would concider making "multiple objects in blender and bake them to one map"

anyways...
good luck,
Gaia

You can make it using a 16x256 oblong map (8x128 cilynder) but LOD is not good