- [Instructor] We've seen how to adjust the scale
of a map within the shading network.
We can use the UVW transform node,
and there are other ways to do it,
but that's only half of the story.
Setting the scale or tiling of a map
within the shading network defines the properties
of that shading network,
but it has nothing to do
with an actual object in your scene.
The object also has to have UVW mapping coordinates
in order to specify how that material shading network
is going to be applied onto the specific object.
And I've got a version of my travertine floor here,
in which we can see that we've got very large tiles.
And this is because I currently have the default
mapping coordinates that are generated by an extrude.
I select that object, go over to the modify panel.
We'll see that in the extrude modifier
there's a switch, Generate Mapping Coordinates.
And if we turn that off we don't get any
material texture there.
And that's just stretching one tile of our material
shading network across the entire object.
All right, well, if we want to control this and set
the tiling and placement manually,
we'll apply a modifier called UVW Map.
Go to the modifier list and scroll down.
And there are lots of UVW modifiers here.
The one we want is just ordinary UVW Map, choose that.
And when it's applied we actually don't see any change
in our mapping.
And that's because it too is defaulting to stretch
the material to cover the entire area of the object.
And there are a lot of options here,
we're not going to explore all of them.
But the most basic ones are the dimensions.
Here, we have length and width,
and they're set to 20 meters each because the object is
20 meters on a side, but we can change this.
I can set the length, for example, to let's say 5 meters,
and now we can see we're stretching our texture
across the surface there.
Alrighty.
So I can set the width to 5 meters as well.
And now I've got a square pattern.
And if we look closely in these various views
we may see a little orange line, or a box,
or a plane, that is the gizmo for the UVW Map modifier.
That allows us to interactively scale and position
the mapping coordinates.
Go into the UVW Map modifiers sub-object types,
and choose Gizmo.
And I'm going to move that up in my perspective view.
Just move that up in Z.
And you can see there's the gizmo.
And if I move in Z, I'm not actually affecting the mapping,
and that's because the mapping is projected orthogonally
at right angles from the mapping plane onto the object.
And so changing the Z elevation doesn't change
the projection.
But if I move it in X or Y in any view,
we can see that indeed we are changing the mapping.
As I said, you can also change the scale factor
using the gizmo, but I don't recommend that,
and here's why.
If we grab the scale tool and then scale this up or down,
we are affecting the tiling.
If we scale this up until it's basically the same size
as the object, then the effective tiling here
is about 20 meters.
But we still have a numeric value here of 5 meters.
That's very misleading.
We actually can't access the numerical scale value
that we just input using that gizmo.
If we right click on the scale tool, it says 100%.
Once we scale that, then we permanently break the connection
to the actual length and width.
I do not recommend that you do this, do not scale the gizmo,
just change its length and width.
So I'm going to undo that with Control + Z.
But positioning really isn't an issue.
We can grab the move tool and move that
mapping gizmo around.
Maybe get in real close in the top view,
Control + Alt + middle mouse.
I can pan with middle mouse and I can align this
so that for example, the tile grout lines up
exactly with the geometry.
Okay, and then I can exit out of Gizmo mode.
This is a pretty simple example
in which we've got a plainer projection.
We can see the default mapping type is plainer,
but as you see, there are a whole bunch
of other mapping types.
If you have spherical or cylindrical object,
then you'll want to choose the appropriate map type.
But this is just a basic introduction.
We barely scratched the surface of UVW mapping here,
but that's enough to get you started.