- A modifier is a program module that affects an object
and it'll be found in the Modify panel.
The most immediate application for modifiers is in modeling.
So for example, we can take a two dimensional spline
or a curve-based object,
and apply an extrude modifier,
and turn that into a 3D object.
Let's do that to create a very simple wall
that will be square in shape.
We'll create a rectangle primitive.
In the Create panel, go to shapes, go to rectangle.
And in the perspective view, click and drag
to create that rectangle, release the mouse,
right click to exit rectangle creation,
and then go to the Modify panel
and let's change up the parameters.
My scene is set to meters.
I'll give it a length of 20 meters,
press Tab and set the width to 20 meters as well.
And we can position that at the origin
just to make things clean.
It's currently selected, go to the select and move tool
and just make sure that the X, Y and Z values are all zero.
And then we can go back to select object,
and let's zoom extends all selected
so that now we frame that object in all the viewports.
Now, if we just applied an extrude modifier
to this rectangle as it is now, we would get a box.
There would be no benefit to doing that
because we could just use a box primitive.
But if we made this a dual shape,
if it had an inner and an outer curve,
then that would give us an extruded wall.
So let's do that.
In order to create this dual shape
with an inner and an outer curve,
we can use the outline to tool.
That's found in the editable spline tool set.
This is currently a rectangle primitive,
we'll want to convert it to editable spline to proceed.
With that rectangle still selected,
right click, and at the bottom right,
choose convert to editable spline in the quad menu.
Once that's done, it's no longer a rectangle primitive.
We no longer have parameters, but we have a whole bunch
of other tools that we didn't have before.
And we can scroll in the Modify panel
and see that there's just really a ton of stuff in here.
And in fact, there's so much that I want to make
the Modify panel larger.
So I can just click on this divider here
and drag over to the left,
make that command panel a lot larger.
Okay, and we can also maybe change this up,
maybe drag this up a little bit,
give us a little bit more visibility
to some of these panels such as the selection panel,
and that will give us the ability
to select difference sub object types.
As we saw in the previous movie,
we've got vertex or control vertex segment,
which is a line between two vertices and spline.
I want to outline this entire shape.
So let's be in spline sub object mode to do that.
And the tool we want is going to be found
in the geometry rollout.
And it's down near the bottom, it's called outline.
And we could click on that
and just simply click and drag to create an outline.
All right, that's very cool.
But I want a little bit more precision.
So let's undo that with Control + Z,
and I can just type in a numeric value here.
Let's give it an outline amount of 0.25 and press Enter.
Now we've got another curve
that is exactly 25 centimeters away
from the original curve in all directions.
And we can zoom in here in the top view,
Control = Alt and middle mouse,
you've got a consistent distance of 0.25 meters
between all of the points
on each one of these two splines.
All right, so I can exit out of outline mode.
I can actually click on that button a second time
and that'll turn it off.
Now we're ready to apply our extrude.
To do that, we want to be in object mode.
So we'll exit out of sub object mode
by clicking on the Spline button again.
And we can go back to our select object tool
just to declutter the interface a little bit,
and we don't need to see that move GIZMO.
And now let's apply our modifier.
That's done by choosing it from the modifier list.
Let's pull down list up here,
click on the down facing arrow.
And we want to scroll down a little bit.
We're looking for extrude, not face extrude,
but just plain old ordinary extrude.
This will operate on spline curves.
Select that, and it added to the top
of that editable supply object.
Now we have two entities here in the modifier stack.
So the stack goes from bottom to top,
and as we continue to add things,
we can get more and more complex effects.
That extrude modifier is currently selected.
If we selected editable spline,
we'd see all of its parameters and tools.
If we choose the extrude modifier,
we have access to all of its parameters and tools.
We need some amount to the extrude
right now it's just creating polygon shape
that has a height of zero.
If we dolly in with Control + Alt and middle mouse,
we'll see it actually is solid, it's got a shape.
Okay, I'll zoom back out again with the Z key,
give it some non-zero amount.
We could click and drag on that and give that some height.
Let's give it a precise value
of four meters and press Enter.
There's more options in here.
For example, there's capping.
We could turn caps on and off.
Let's keep them on in this case,
or we could choose to output to different object types.
We're going to leave that at mesh.
All right, that's pretty cool, we've got our extruded shape.
The beauty of 3ds Max and the modifier stack
is that it permits a non-destructive workflow
which is quasi parametric.
We could create a parametric primitive
and then apply parametric modifiers, for example,
like a bend or taper or twist or something like that,
and create some kind of shape.
And that would be a completely parametric workflow.
But here we have the ability to actually combine
a destructive or editable workflow
with a non-destructive or parametric workflow all at once.
And to do that, for example,
I can go down to the level of the editable spline,
and now we don't see the extrude modifier,
it's not being applied in our viewports.
If we wanted to see it,
then we would enable this button here, show end result.
When that's on,
we'll see the result of the entire modifier stack
regardless of what level we're currently selecting.
If that's off, then we'll only see
the modifier stack up to and including
the currently selected level of the stack, okay.
So, we can now go in and edit this spline.
For example, we can go in and select maybe segments,
click on segment, and click and drag to select
a couple of those segments, and then grab a move tool again,
maybe dolly back out in the top view,
Control + Alt and middle mouse, pan with middle mouse.
And I can drag that and change that shape.
I'm not just changing the shape of the spline,
I'm also changing the shape of the 3D object
that's generated from the extrude modifier.
If I turn show end result back on again, we can see that
we can actually edit this shape, quasiparametically.
In other words,
we're doing an editable destructive operation here
with the editable spline base object,
but we also have the ability to go back up
and change the parameters of the extrude.
I can exit out of segment sub object, go back up
to the extrude modifier and choose a different height.
Let's say I want an amount of six meters instead of four.
All right, so that's a basic introduction
to the modifier stack, and the really cool ability
of 3d Max to combine a destructive
and a non-destructive workflow within the same object.