A major enhancement to the Voronoi Fracture generator is the addition of
detailing. Detailing allows us, amongst other things, to add fine details to the
interfaces of the fractured object while retaining the outer shape intact.
The result of detailing, as shown in these examples, can add a lot of high fidelity
to your fracturing scenes. Let's take a look at how detailing works
and all of the settings associated to it. The simplest way to show this to you is by
fracturing a cube. So here's a primitive cube, and let's go
and add a Voronoi Fracture generator. Make the cube
a Child, and we have our default Voronoi Fractured cube.
Let's change a few things. Number one, I'm going to get rid of the colorization.
Number two, I'm going to activate the line so we can see the fragments.
Number three, with the Voronoi Fracture selected, I'm going to go and add a Push
Apart Effector and set this to 60 so we can see the inner faces.
And what I'm going to do is create a new material, double-click in the Material
Manager, double-click on the material. I'm going to set the color to something like a
light orange. Drag it on my Voronoi Fracture. Select the Voronoi Fracture.
Go to the Selections. Expose the inside faces, and with the texture tag selected,
drag the selection into Selections. And now we have a clear indication what's an
interface and what's an outer face. So, with the prep work done in about a minute,
select the Voronoi Fracture. Go to the Detailing tab. Pull this up,
and let's activate the Detailing. What happens is that the whole model gets
tessellated and not only that. What we are seeing here, if I turn the Gouraud Shading
on, is that now we have this nice little deformation inside here. And
if I turn it off, you'll see they're flat. If I turn it on, we see that they have the
detail. That's why it's called Detailing. So Activate in Viewport,
this is just to flatten things in the Viewport, but it will render the same in
the picture viewer anyway. It's just to save some speed in the Viewport.
So let me just activate it again. Now, let me turn on my lines one more time.
The maximum edge length defines the resolution of these triangles,
so I'm doubling it, which means the triangles are bigger, which means we have
less definition. So you decide how small or large your details are.
Let me make it 10 again. Sometimes it takes a few seconds to recalculate,
if it doesn't recalculate in a couple of seconds, press A to force a recalculation.
Noise Surface, I'm going to click this, and what you see here is the following.
I'm going to zoom into this edge. This is the common edge between the outer face and
the inner face, and currently, it's straight. It's the same direction,
exactly the same edge, as if the detailing was disabled. So if I say Noise Surface
what will happen is that although my surfaces are still straight,
you can see they're straight, it doesn't have any deformation,
this Edge is going to be more jagged. And this allows for a more organic look of
your broken object. The only problem with this is that if your
Noise Strength which defines how much the object is going to be deformed is a bit
too much, what will happen is that you may start getting artifacts.
In this case, you are going to use this value here and increase it and actually
bring back some of the original shape of this particular edge,
so to speak we can just smooth it out. So let me turn this off. Now,
Smooth Normals, these normal settings have everything to do with the inside faces and
nothing to do with the outside faces. So let's take a look here.
If I turn off Smooth Normals, you can see that my Normals are gone, and now I have
faceted triangles. This is good if you're trying to make some sort of object which
is made of a material that has more crystalline nature. So
if I render this, you'll see that we have the facets, but as if this is on, you see
that it's nice and smooth. And the smoothness pertains to the rendering.
It's a Phong smoothness, not a geometry smoothness. So, this is the default.
Use original edges. So, let's take a look at this. I'm going to
turn it back on, and I'm going to go somewhere where we have some sort of inner
edge. There we go. So, look at this edge here.
This edge connects two inner faces. Now, if I turn this off, you see we have one,
one, two inner faces. So, here's the edge now, and it's jagged. When I say use
original edges, then the Phong angle between these two faces
is going to be retained. If I turn it off, then you
can see that some smoothness has already been applied
at this spot, and the more I increase this number, the more these edges smooth.
But be prudent with this because it can get out of hand and create all sorts of
Normal artifacts. So, Relax Inside Edges, what this will do, it will actually start
relaxing the triangles of the inside faces so that the resulting detailing is a bit
smoother. So this gets applied on the geometry, not on the Phong.
So let's pull out. Now, this is an interesting one, Keep Original Surface.
If I turn it off, then my deformation gets applied to the whole object.
And what I'd like you to see is that when this is off, then the strength at depth is
deactivated. When it's on, the strength at depth is activated. I'll show you what it
does in a second. Let's go down to the Noise Settings. This
is driven by a noise, just like a noise we use in the displacer or our textures or
anything else. So you can go and select any of the well known noises from Cinema
4D. This defines the Noise Strength, the Seed, which changed the randomization,
Octaves, Global Scale, to make the noise tighter or broader, a Relative Scale,
Animation Speed, if you want to animate the noises. That's fantastic.
Rewind, click on this, and what I realize is we have these artifacts here.
This is a result of using the Keep Original Surface On and Off.
It will introduce some artifacts. You press A to force a refresh, and that will
get rid of that. Let's continue down here. After the
animation speed, which we'll turn back to 0, we have the Low Clip and the High
Clip which is nothing more than changing the contrast and brightness,
I guess, or tightening the gradient that controls the noise. And finally, the
strength at depth. So let's go and zero the relaxations so we can see more detail.
Make this 50. I'm doing this on purpose. Although some of you may find it nice.
So the left side of this spline degree has to do with the outer parts of the inner
faces, and the right side has to do with the inner parts. And what this means is
how much of the deformation is going to be applied to each face,
by checking what is close to the edge and what is close to the center.
Let me show you. I'm going to take these knots and put them down.
And now you can see that all the triangles that are closer to the outer surface of
our object receive less of this value. And this is because some objects break
differently close to the surface and differently inside. If it's a porous
material, you have a larger deformation in here.
Maybe I'll make this 20, make it a bit more palatable.
On the other hand, if I do the opposite, then what I'm doing here is I'm removing
the deformation from the center of the face and keeping it only on the sides.
Depending on what type of material you're trying to depict, one of these settings is
going to help you do it. There's one more thing I'd like to mention,
and it has to do with dynamics. So I'm going to right click and add a Rigid Body
tagged to the Voronoi Fracture. What I'd like you to observe is that there's a new
setting in the Collision tab called Use Deformed Object. Now, this is Off by
default. And what this means is the following, the detailing displacement is
actually a deformation. And because this deformation may cause objects to
intersect, and it will cause some sort of explosive reaction when we activate
dynamics, when this is off, the dynamics calculations are going to be calculated as
if the interfaces do not have the deformation. So, imagine if there was no
Detailing or the Noise Strength was 0, this would be the shape that will be used
when this is off. If for any reason you want to use the actual deformed state with
the high detail, then you turn this on. But it's not really advisable because your
simulation is going to be much slower and much more explosive.
So these are the detailing settings of the Voronoi Fracture generator in a nutshell.