Original subtitles

In this lesson,

we're going to learn how to merge shapes together to create a cut out.

OK, so I've already gone ahead and set up a little Node tree for us here.

And I want to go ahead and kind of just show you what's going on.

So I've gone ahead and created a rotoscope that is-- or actually a couple

of rotoscopes that are isolating both of these bottles.

And then we have a color correction node that is being applied to our whole

Read node and then is being masked by that rotoscope.

So let's go ahead and open up the Roto node so you can see those two shapes.

We've got our tall bottle and our short bottle.

So we've got both of those names just to stay organized a little bit better.

And you can see how they overlap with each other.

Now that's the important part.

They're animated so that at the beginning there aren't really overlapping,

but towards the end,

we maintain that point consistency where it's all

around the sides of these bottles.

And so we're able to keep this edge on this tall bottle here.

And we're able to see that shape that it creates as

it goes behind the shorter bottle.

So what if we want to create a cut out where we're only

looking at one or the other bottles?

Well, there's an easy way to do that,

but we have to change our set up a little bit from what it is right now.

And the way we have it set up right now is that we've got both

of these Bezier shapes on one Roto node.

And they need to each be on a different Roto node for this method to work.

Now this is also useful if you ever create some kind of a

shape like this on a Roto node and you really need it to be

on a different Roto node entirely.

You don't want to store them all on the same thing.

And you might do that for a number of reasons.

But, besides learning how to create a cut out,

you're also going to learn how to take a Bezier shape out of a

Roto node and put it into a different one.

So let's go ahead and get started.

I'm going to go ahead, and we'll create our second Roto node now.

So just without anything selected,

I'm going to come up here to our draw button and choose Roto.

We'll drop that in, and not connected up to anything right now,

all we have to do is to simply look at what we've got here in our Roto 1,

and let's decide to take the short bottle and we'll put that in Roto 2.

So all I have to do is simply drag it.

So I'm going to grab the short bottle that's here in the root of Roto 1,

and we'll just drag it up and drop it on the root of Roto 2.

So now, the short bottle lives inside of Roto 2,

and the tall bottle is still in Roto 1.

So you can see I can click back and forth between those two nodes,

to see the different shapes that have been being created.

And now, more importantly, we have the ability to merge these two nodes together.

So I'm going to disconnect the matte support for just a second.

So let's go ahead and merge these two Roto nodes.

So I like to just hover my mouse over the open area in my Node graph,

hit the Tab key and we can type in merge.

Or you can even just hit the N key, and that'll drop in a Merge node for you.

Now, depending on which one you want to be cut out,

it's going to matter which A and B pipe is connected to which Roto node,

but for now, let's just go ahead and connect them up,

and just see what happens.

So you always want your B pipe to be straight up and down,

so I'll go ahead and put that B pipe straight up and down there.

And then we'll put the A pipe over here to the side.

And let's pull this up just a little bit like that.

And then we just need to grab the Mask port of our color

correction and drop it onto our Merge node.

So now, you can see that we basically have the same look as what we had earlier,

but we have individual control over the Roto nodes because of the Merge node.

And so we can change the way that they are being mixed together,

the way that they're overlapping with this operation.

So right now, the operation being over, we don't see much of a change.

But if I change it to the from operation,

you can see that now,

only the short bottle is being affected by the color correction.

So only Roto 2, which is on our B pipe is being affected.

Now if I unplugged those and we switched them so that the tall

bottle was what was connected to our B pipe,

now you can see that this one is a little more saturated.

So it just depends on whichever one is your B pipe is going to be the one

that will be affected if you're using the From operation.

So, pretty interesting the way that that works out.

So now we've got our short bottle being saturated by this.

And just to help you visualize what this looks like,

I'm going to select that From-- or excuse me,

the Merge node that has the From operation,

and then we can come up here to the style that we want to view this as and,

change it to be Alpha,

and you can see if we move our Viewer here to the Merge Node,

you can see the Alpha of that cut out.

So now,

you can see how that From is affecting the Alpha channel of the short bottle.

So pretty interesting the way that that works.

And that's a really useful technique you can use for lots of different

kinds of Rotoscopes that you might need to create.

Sometimes something's going to pass behind or in front of something else,

but you want to maintain that point consistency,

maybe because you know it's going to come out from it on the other side.

So you simply use a From operation to isolate that,

even while it's passing behind other things.

So really, really interesting technique.

Really easy to execute.

You just have to kind of do a little bit of planning.

And even if you don't plan for it, as I showed you,

can transfer a Bezier shape to a different Roto node.

So that you can have that merge operation and that seems to work really,

really nicely.

In the next lesson,

I want to talk about how you can reuse key frame data through

your viewer to help speed up your animations.

So we're going to learn how to do that in our next lesson.