- [Voiceover] All right, now one of the interesting things
about object blends is that when the two extreme shapes
are far apart from each other, as they are in this case,
we have this thing called the spine in between,
and to see that spine, I'll go ahead and select it
using the white arrow tool, that's very important,
by marqueeing through the central portion
of the intervals like so,
at which point you will see this path outline
between the center of the square
and the center of the circle,
and that is the spine, incidentally,
and what it amounts to is the path along
which the blend progresses,
and now notice if I go up to the Object menu,
choose Blend and then choose Reverse Spine,
that'll reverse the direction of that path
and it'll also reverse the direction of the entire blend
as you can see here,
and by the same token,
if I go ahead and grab this anchor point
at the end of the path outline,
this is the end of the spine,
and this is the beginning, incidentally,
if I go ahead and drag this anchor point down
and to the right, I'll move the circle along with it
and the same goes if I drag the first anchor point,
I'll move that rounded square.
All right, that's not really the effect I'm looking for,
however, and so, I'll go up to the File menu
and choose the Revert command
in order to restore the document that we saw
at the beginning of the movie.
All right, now what I want you to see here
is the distance between the intervals.
Notice that they're packed more tightly here at the end
of the blend, toward the circle,
than they are toward the beginning of the blend
at the rounded square.
We can control that by modifying the spine,
so I'll once again marquee in an empty portion
of the illustration as you're seeing here,
just through the intervals so that we're selecting the spine
without the circle or the square,
and now what I want you to see is that this is just
a straight path outline.
We've got a corner point at one end
and another corner point at the other,
no control handles whatsoever,
but if we were to add control handles,
then we'd have greater control over both the direction
and the speed of the blend.
And to demonstrate that, I'll go ahead and click and hold
on the Pen Tool and choose the Anchor Point Tool
from this fly-out menu,
or you can press the keyboard shortcut of shift + "c".
Now I'll just go ahead and drag from this corner point,
in order to draw forth a couple of control handles,
so we now have a smooth point,
and I'll drag from this guy as well,
and it appears I was moving in the wrong direction
both times, but,
if that happens to you, all you have to do
is reverse your direction as I've done,
and now notice, if I press the "a" key to switch back
to my white arrow tool,
then I can go ahead and drag these control handles
in order to modify the direction of the blend,
like so.
Another option is to keep your control handles aligned
with the path outline,
and that's going to require me to drag a couple of times,
in which case you'll end up with a straight blend
as we're seeing here,
but notice as I move the control handle,
I'm changing the distance between the intervals
so I'm actually controlling the speed of the blend,
and at some point, I'll see that the intervals
are more or less evenly spaced.
Now, the other thing I want you to notice at this point
is that we have some lumpiness.
Can you see that there?
Right at the top of these early shapes.
And the reason for that is,
if I go ahead and click on a square to select it,
and then I'll drag one of these corner widgets
in order to return the shape's sharp corners,
then notice that it has a total of four anchor points
and they're all located in the corners.
Compare that to the circle,
which has anchor points at the top,
the bottom, and the two sides,
if that were to say we were looking at a circle
instead of a pie.
All right, now I'll go ahead and switch to the Ellipse Tool
so that I can see my live shape widgets
and I'll go ahead and drag this pie widget
so the two are aligned with each other,
to restore a circular shape,
and notice now how smooth things are
and that's because, at least in my case,
the anchor points have moved,
so that in other words, the ellipse has rotated 45 degrees
and to show you the difference here,
I'll go ahead and hover my cursor close to
but not directly on one of the corner handles,
and I'll press the shift key as I rotate this shape
into its standard orientation
so that I have anchor points at the top, the bottom,
and the two sides,
and notice now that we have a little bit of lumpiness
going on, so we've got these kind of points
at the top of our initial intervals.
Compare that to what happens if I rotate the shape
45 degrees, so that the anchor points
are now located in the corners
and I have corners in air quotes, by the way,
because we don't really have corners with an ellipse,
but we do have anchor points at analogous locations,
so in other words,
those anchor points match the locations
found inside the square
and as a result, we have these very smoothly
transitioning intervals,
and that's because object blends rely on anchor points
in order to do their work,
and we'll see more about how that affects real world
blends in future movies.
All right, I'll just go ahead and press
control + shift + "a"
or command + shift + "a" on a Mac in order to deselect
my artwork and I'll turn off the Guides layer as well,
and that's how you either redirect a blend
or change its speed
by editing its spine, here inside Illustrator.