- Usually at the end of
a subdivision surface modeling project,
you'll need to bake the subdivisions
or burn them in
and make that level of detail permanent.
There are many reasons why you might want to do this.
For example, maybe you're exporting
to an application or a real time engine
that does not support the open subdivision algorithm,
you need to convert to polygons before exporting.
Another very common reason
for baking SubD's, is to allow fine adjustments.
We cannot access the individual subdivided polygons.
Therefore, we can't perform low level rigging
or modeling operations.
If I select this seat cushion object,
go over to the modified panel,
and disable Isoline Display.
We can see the individual polygons.
I'll zoom in on that with the Z-key.
So we can see these,
but we can't select them directly.
The tessellation or subdivision of that object is dynamic.
We can change the number of iterations,
bring that down to one,
and we've got fewer subdivisions,
or increase that up to three,
and we have more tessellation.
Okay, I'll set this back to iterations of two.
We actually can select these subdivided polygons
using a selection modifier placed higher in the stack,
but then we would probably run into issues
with performance,
or future proofing,
or topology dependence,
as we discussed earlier in the course.
It's almost always a better move
to simply collapse the stack,
and delete all of these modifiers
by converting the object,
to editable poly.
In the case of this model,
I want to do that,
so that I can separate the seat cushion into two pieces.
I want a soft cushion above,
and I want a harder plastic base below.
One way we might try to do this,
is by detaching the parts of the original editable poly,
or control cage,
and then subdividing those two objects,
or elements separately,
as two disconnected control cages.
But in that case,
it's very likely that we get a gap,
and or an overlap at the open border
between the two polygon shells or elements.
There's supposed to be a perfect joint between those two
but we'd end up with, you know,
a really messy situation.
If we bake in the subdivisions
and then detach the individual polygons,
we can be sure that those two parts
will align perfectly.
So let's now bake this
and make the level of detail permanent.
With the object selected right click in the view port,
and choose convert to,
convert to editable poly.
And now we've just baked the cake.
Now let's perform the detach operation.
To start with that,
I want to select the edge loop,
where I want to split the two polygon shells,
by getting close, control, alt and middle mouse,
going to edge sub-object mode,
and double click on the edge that we want to separate,
so double click on this edge at the corner there.
And then in the edges panel,
click on the split button.
It divides the mesh along the selected edges,
click that.
We don't see anything change on our display here,
but now we actually have two disconnected polygon shells,
also known as elements.
We can go into elements, sub-object mode.
Click on one of those.
And all of those polygons are selected,
or click on the base here,
and all of those polygons are selected.
We've just chopped this into two disconnected elements,
also known as polygon shells.
So let's detach this base now.
So select it.
And we're in element sub-object mode.
And in the geometry panel,
click detach.
we get a popup window.
We want to give the new object a name,
I'll call this chair task seat base.
And we don't want to just detach to element.
It's already an element within the current object.
We want to detach to a separate object
and we don't want to create a copy.
If we chose detach as clone,
then we would create a new copy of this element
but the older element would still be left behind
in the chair task seat, cushion object.
So with both of those options turned off, we'll click okay.
We can exit out of element sub-object mode
and now we've got two completely separate objects.
So we can click on this one here.
We can see that it's a separate object,
chair task seat base,
and we've got the selection outlining
in blue indicating that's a separate object.
All right,
and they're perfectly aligned.
Just a minute ago,
They were actually welded,
but now they're two separate objects,
that are precisely aligned.
That's how to bake subdivisions,
to make low level modeling adjustments.
And it concludes our chapter
on subdivision surface modeling.