ZSpheres

The main idea of ZSpheres is to quickly set up a linked hierarchy, that is then “skinned” resulting in a mesh that can then be developed with ZBrush modeling tools.

There are two methods to skin ZSphere models.
We will work with Adaptive first.

Let’s get started ...

Draw a ZSphere in ZBrush 3.0
Position it in the center of the canvas.
This will be a biped’s center of mass.

 

T = turn on Edit.

X = turn on X symmetry

Note -- at the middle the cursor turns green

 

Hold down Shift and click a couple times.
Shift makes multiple ZSphere the same size.

Hold down shift and move up

Hit A and you can see the skin
(More on that later)

 

When the spheres are red, they will create a twin ...
Green goes up the main line of the figure ...

 

Tips
Q = draw
T = edit
W = move

These links and handles allow your to rotate limbs

  

Make sure you select the red/green circle
if you only want to effect that ZSphere

Scaling a ZSphere:

 

Scaling a link:

 

In draw mode
Alt-click on a ZSphere if you want to delete

 

All the ZSpheres should (in theory) face the same way.

  to

Turn off X symmetry when rotating the head, pelvis, in other words, non-twinned items.

Adaptive skinning
This is the most used method.
It is usually fairly low-res, to start roughing out a model quickly.

The critical thing is to toggle A to check your skinning results as you proceed with the ZSphere.

This is in the Tools menu.
Preview is the most often used button

Explanation of settings:

Density
Sets the density/resolution, like subdivide.

Density 1 ... and density 4:

 

Ires
Intersection Resolution
The number of child links above which the model will subdivide
Note -- does not include Attractor Zspheres

Mbr
Membrane Curvature
How polys are created at L and T intersects

Settings of 0, then 100:

MC
Minimal skin to Child
How polys are created at intersections ...
Turn this off or on and observe results

MC on makes a very minimal terminal mesh:

MC off makes a more complex, rounded mesh:

This has a big effect inside armpits, shoulders, neck, the crotch, etc.

Mc on:

Mc off:

MP
Minimal skin to parent
This makes a more rounded intersection ...

MP on does not add polys at intersections:

MP off might add polys at intersections:

Polygroups
When a path splits, the polygroup color changes

 

Ctrl shift Click on a polygroup to hide inverse

 

Xres, Yres and Zres
These settings are for the next ZSphere that is drawn.

This determines the mesh resolution.

Each ZSphere is treated as a cube.
The number of polys along each edge are determined by the
Tool:Adaptive Skin:IRes setting.

Change and see the results

 

Try this ... change Xres to 3 ... they all change.

Now, make Zres = 2
(The Z-axis is the line between the ZSphere and its parent)

Hit 2, press shift
While holding shift, hit enter

This shows adaptive skinning going from 1, to 2, to 3.

Attractor Spheres
Attractor spheres push and pull the geometry of the skin.

Make a new linked ZSphere where you want an attractor
It should attach to the ZSphere you want to influence

Alt click on the last child ZLink of a chain

 

The attractors can be selected and moved or scaled.

 

The trick to moving attractor spheres
Click on the link to make it active first
A small red circle must appear in the center of the attractor

 

Move the mouse to get a little red line connected to a brighter red circle to appear

Drag

On feet, to create heels:

Make a terminal ZSphere first

 

Alt click on the chain, to convert to an attractor ...

 

Move or scale the attractor and observe results:

 

Make Adaptive Skin

 

To make the mesh a new tool
Hit Make Adaptive Skin

This makes a new tool named “Skin_” ...
It is not immediately active.

Hit A to see the mesh on the ZSpheres ...
... or hit the preview button

The resulting tool at lowest (1) and a higher res:

 

Work with Tweak, Inflate, and smooth and see where you can take the model ...
... and how fast ... you are on your own ... ZSpheres helped you get a fast model,
once you learn all the above.

Unified skin
Finally, a brief example of unified skin ...
This is far more precise, exactingly fitting the ZSpheres.
The defaults:

 

Note -- Attractor ZSpheres have no effect in Unified.

If a ZSphere doesn't affect the skin:
Increase the density of the skin or,
Enlarge the ZSphere.