- [Instructor] Under the analysis tab,
we have tools for display.
Display allows you to show the poles and knots
of the surface that you're dealing with or curves.
I'll specify the primary,
and these are like switches.
I'm going to turn on the poles.
I'm going to turn on the knots.
And once those are turned on,
they stay on for that surface.
Notice that they don't show on at the moment,
but as soon as I pick that surface, they come back on.
Here you can see I have my control points,
so I'm seeing the poles of the surface.
If I were to go into XForm and use that tool on the surface,
this is exactly what I would see.
This is a really good way to visualize
what's happening with the surface, to see quality,
make sure you don't have any
weird things happening with the surface,
'cause the control points all look good.
They're very smooth.
Pick that surface, turn that off, and turn that off.
I didn't see any knot points, because it's a primary
and I made it very cleanly.
I'll do the same thing with this blend.
Select my blend, show poles.
You'll see that I have a very clean poles
running across that blend.
And then show knots, no knot points.
Turn those off again.
Pick this corner, and I'll show knots,
and as you can see, I have one knot
running across the surface.
That knot is indicating that internal to the surface
there is an additional patch.
Because this is a corner,
these are going to be a bit more complex.
These are typically the most complex surfaces,
so you expect to see knots in some cases.
If you can minimize these, obviously minimize them,
but sometimes they just happen to have to be on the surface.
I'll show the poles, and as you can see,
it is by far the most complex of the surfaces.
So using your display tools in such a fashion,
you can get a good indication of what's going on
with the primary or secondaries,
and of course the tertiaries.
And as you go across them,
pay close attention to the level of complexity
that you can visually see
based off of those poles and knots.